Search Results

Search found 4240 results on 170 pages for 'delayed execution'.

Page 52/170 | < Previous Page | 48 49 50 51 52 53 54 55 56 57 58 59  | Next Page >

  • Is SQL Server DRI (ON DELETE CASCADE) slow?

    - by Aaronaught
    I've been analyzing a recurring "bug report" (perf issue) in one of our systems related to a particularly slow delete operation. Long story short: It seems that the CASCADE DELETE keys were largely responsible, and I'd like to know (a) if this makes sense, and (b) why it's the case. We have a schema of, let's say, widgets, those being at the root of a large graph of related tables and related-to-related tables and so on. To be perfectly clear, deleting from this table is actively discouraged; it is the "nuclear option" and users are under no illusions to the contrary. Nevertheless, it sometimes just has to be done. The schema looks something like this: Widgets | +--- Anvils (1:1) | | | +--- AnvilTestData (1:N) | +--- WidgetHistory (1:N) | +--- WidgetHistoryDetails (1:N) Nothing too scary, really. A Widget can be different types, an Anvil is a special type, so that relationship is 1:1 (or more accurately 1:0..1). Then there's a large amount of data - perhaps thousands of rows of AnvilTestData per Anvil collected over time, dealing with hardness, corrosion, exact weight, hammer compatibility, usability issues, and impact tests with cartoon heads. Then every Widget has a long, boring history of various types of transactions - production, inventory moves, sales, defect investigations, RMAs, repairs, customer complaints, etc. There might be 10-20k details for a single widget, or none at all, depending on its age. So, unsurprisingly, there's a CASCADE DELETE relationship at every level here. If a Widget needs to be deleted, it means something's gone terribly wrong and we need to erase any records of that widget ever existing, including its history, test data, etc. Again, nuclear option. Relations are all indexed, statistics are up to date. Normal queries are fast. The system tends to hum along pretty smoothly for everything except deletes. Getting to the point here, finally, for various reasons we only allow deleting one widget at a time, so a delete statement would look like this: DELETE FROM Widgets WHERE WidgetID = @WidgetID Pretty simple, innocuous looking delete... that takes over 2 minutes to run, for a widget with no data! After slogging through execution plans I was finally able to pick out the AnvilTestData and WidgetHistoryDetails deletes as the sub-operations with the highest cost. So I experimented with turning off the CASCADE (but keeping the actual FK, just setting it to NO ACTION) and rewriting the script as something very much like the following: DECLARE @AnvilID int SELECT @AnvilID = AnvilID FROM Anvils WHERE WidgetID = @WidgetID DELETE FROM AnvilTestData WHERE AnvilID = @AnvilID DELETE FROM WidgetHistory WHERE HistoryID IN ( SELECT HistoryID FROM WidgetHistory WHERE WidgetID = @WidgetID) DELETE FROM Widgets WHERE WidgetID = @WidgetID Both of these "optimizations" resulted in significant speedups, each one shaving nearly a full minute off the execution time, so that the original 2-minute deletion now takes about 5-10 seconds - at least for new widgets, without much history or test data. Just to be absolutely clear, there is still a CASCADE from WidgetHistory to WidgetHistoryDetails, where the fanout is highest, I only removed the one originating from Widgets. Further "flattening" of the cascade relationships resulted in progressively less dramatic but still noticeable speedups, to the point where deleting a new widget was almost instantaneous once all of the cascade deletes to larger tables were removed and replaced with explicit deletes. I'm using DBCC DROPCLEANBUFFERS and DBCC FREEPROCCACHE before each test. I've disabled all triggers that might be causing further slowdowns (although those would show up in the execution plan anyway). And I'm testing against older widgets, too, and noticing a significant speedup there as well; deletes that used to take 5 minutes now take 20-40 seconds. Now I'm an ardent supporter of the "SELECT ain't broken" philosophy, but there just doesn't seem to be any logical explanation for this behaviour other than crushing, mind-boggling inefficiency of the CASCADE DELETE relationships. So, my questions are: Is this a known issue with DRI in SQL Server? (I couldn't seem to find any references to this sort of thing on Google or here in SO; I suspect the answer is no.) If not, is there another explanation for the behaviour I'm seeing? If it is a known issue, why is it an issue, and are there better workarounds I could be using?

    Read the article

  • JAVA BubbleSort Output Plotting

    - by John Smith
    I'm not sure how to plot the output I get with my run time results for BubbleSort. Here's the thing: I've written a working BubbleSort algorithm that does exactly as it should. But I wish to plot the output, to show the following: Best Case, Worst Case, Average Case ... How would I go about plotting it on a graph? Here is the code: public class BubbleSort { static double bestTime = 10000000, worstTime = 0; public static void main(String[] args) { int BubArray[] = new int[]{13981, 6793, 2662, 10986, 733, ... #1000 integers}; System.out.println("Unsorted List Before Bubble Sort"); for(int a = 0; a < BubArray.length; a++){ System.out.print(BubArray[a] + " "); } System.out.println("\n Bubble Sort Execution ..."); for(int i=0; i<10000;i++) { bubbleSortTimeTaken(BubArray, i); } int itrs = bubbleSort(BubArray); System.out.println(""); System.out.println("Array After Bubble Sort"); System.out.println("Moves Taken for Sort : " + itrs + " Moves."); System.out.println("BestTime: " + bestTime + " WorstTime: " + worstTime); System.out.print("Sorted Array: \n"); for(int a = 0; a < BubArray.length; a++){ System.out.print(BubArray[a] + " "); } } private static int bubbleSort(int[] BubArray) { int z = BubArray.length; int temp = 0; int itrs = 0; for(int a = 0; a < z; a++){ for(int x=1; x < (z-a); x++){ if(BubArray[x-1] > BubArray[x]){ temp = BubArray[x-1]; BubArray[x-1] = BubArray[x]; BubArray[x] = temp; } itrs++; } } return itrs; } public static void bubbleSortTimeTaken(int[] BubArray, int n) { long startTime = System.nanoTime(); bubbleSort(BubArray); double timeTaken = (System.nanoTime() - startTime)/1000000d; if (timeTaken > 0) { worstTime = timeTaken; } else if (timeTaken < bestTime) { bestTime = timeTaken; } System.out.println(n + "," + timeTaken); } } The output are as the following ( execution number, time (nano/10^6): Unsorted List Before Bubble Sort 13981 6793 2662 .... #1000 integers Bubble Sort Execution ... 0, 18.319891 1, 4.728978 2, 3.670697 3, 3.648922 4, 4.161576 5, 3.824369 .... 9995, 4.331423 9996, 3.692473 9997, 3.709893 9998, 6.16055 9999, 4.32209 Array After Bubble Sort Moves Taken for Sort : 541320 Moves. BestTime: 1.0E7 WorstTime: 4.32209 Sorted Array: 10 11 17 24 57 60 83 128 141 145 ... #1000 integers I am looking for graphs to represent Average, Best and Worst case based on the output but my current graphs don't look correct. Any help would be appreciated, thanks.

    Read the article

  • Multi-threaded .NET application blocks during file I/O when protected by Themida

    - by Erik Jensen
    As the title says I have a .NET application that is the GUI which uses multiple threads to perform separate file I/O and notice that the threads occasionally block when the application is protected by Themida. One thread is devoted to reading from serial COM port and another thread is devoted to copying files. What I experience is occasionally when the file copy thread encounters a network delay, it will block the other thread that is reading from the serial port. In addition to slow network (which can be transient), I can cause the problem to happen more frequently by making a PathFileExists call to a bad path e.g. PathFileExists("\\\\BadPath\\file.txt"); The COM port reading function will block during the call to ReadFile. This only happens when the application is protected by Themida. I have tried under WinXP, Win7, and Server 2012. In a streamlined test project, if I replace the .NET application with a MFC unmanaged application and still utilize the same threads I see no issue even when protected with Themida. I have contacted Oreans support and here is their response: The way that a .NET application is protected is very different from a native application. To protect a .NET application, we need to hook most of the file access APIs in order to "cheat" the .NET Framework that the application is protected. I guess that those special hooks (on CreateFile, ReadFile...) are delaying a bit the execution in your application and the problem appears. We did a test making those hooks as light as possible (with minimum code on them) but the problem still appeared in your application. The rest of software protectors that we tried (like Enigma, Molebox...) also use a similar hooking approach as it's the only way to make the .NET packed file to work. If those hooks are not present, the .NET Framework will abort execution as it will see that the original file was tampered (due to all Microsoft checks on .NET files) Those hooks are not present in a native application, that's why it should be working fine on your native application. Oreans support tried other software protectors such as Enigma Protector, Engima VirtualBox, and Molebox and all exhibit the exact same problem. What I have found as a work around is to separate out the file copy logic (where the file exists call is being made) to be performed in a completely separate process. I have experimented with converting the thread functions from unmanaged C++ to VB.NET equivalents (PathFileExists - System.IO.File.Exists and CreateFile/ReadFile - System.IO.Ports.SerialPort.Open/Read) and still see the same serial port read blocked when the file check or copy call is delayed. I have also tried setting the ReadFile to work asynchronously but that had no effect. I believe I am dealing with some low-level windows layer that no matter the language it exhibits a block on a shared resource -- and only when the application is executing under a single .NET process protected by Themida which evidently installs some hooks to allow .NET execution. At this time converting the entire application away from .NET is not an option. Nor is separating out the file copy logic to a separate task. I am wondering if anyone else has more knowledge of how a file operation can block another thread reading from a system port. I have included here example applications that show the problem: https://db.tt/cNMYfEIg - VB.NET https://db.tt/Y2lnTqw7 - MFC They are Visual Studio 2010 solutions. When running the themida protected exe, you can see when the FileThread counter pauses (executing the File.Exists call) while the ReadThread counter also pauses. When running non-protected visual studio output exe, the ReadThread counter does not pause which is how we expect it to function. Thanks!

    Read the article

  • PowerShell Script to Deploy Multiple VM on Azure in Parallel #azure #powershell

    - by Marco Russo (SQLBI)
    This blog is usually dedicated to Business Intelligence and SQL Server, but I didn’t found easily on the web simple PowerShell scripts to help me deploying a number of virtual machines on Azure that I use for testing and development. Since I need to deploy, start, stop and remove many virtual machines created from a common image I created (you know, Tabular is not part of the standard images provided by Microsoft…), I wanted to minimize the time required to execute every operation from my Windows Azure PowerShell console (but I suggest you using Windows PowerShell ISE), so I also wanted to fire the commands as soon as possible in parallel, without losing the result in the console. In order to execute multiple commands in parallel, I used the Start-Job cmdlet, and using Get-Job and Receive-Job I wait for job completion and display the messages generated during background command execution. This technique allows me to reduce execution time when I have to deploy, start, stop or remove virtual machines. Please note that a few operations on Azure acquire an exclusive lock and cannot be really executed in parallel, but only one part of their execution time is subject to this lock. Thus, you obtain a better response time also in these scenarios (this is the case of the provisioning of a new VM). Finally, when you remove the VMs you still have the disk containing the virtual machine to remove. This cannot be done just after the VM removal, because you have to wait that the removal operation is completed on Azure. So I wrote a script that you have to run a few minutes after VMs removal and delete disks (and VHD) no longer related to a VM. I just check that the disk were associated to the original image name used to provision the VMs (so I don’t remove other disks deployed by other batches that I might want to preserve). These examples are specific for my scenario, if you need more complex configurations you have to change and adapt the code. But if your need is to create multiple instances of the same VM running in a workgroup, these scripts should be good enough. I prepared the following PowerShell scripts: ProvisionVMs: Provision many VMs in parallel starting from the same image. It creates one service for each VM. RemoveVMs: Remove all the VMs in parallel – it also remove the service created for the VM StartVMs: Starts all the VMs in parallel StopVMs: Stops all the VMs in parallel RemoveOrphanDisks: Remove all the disks no longer used by any VMs. Run this script a few minutes after RemoveVMs script. ProvisionVMs # Name of subscription $SubscriptionName = "Copy the SubscriptionName property you get from Get-AzureSubscription"   # Name of storage account (where VMs will be deployed) $StorageAccount = "Copy the Label property you get from Get-AzureStorageAccount"   function ProvisionVM( [string]$VmName ) {     Start-Job -ArgumentList $VmName {         param($VmName) $Location = "Copy the Location property you get from Get-AzureStorageAccount" $InstanceSize = "A5" # You can use any other instance, such as Large, A6, and so on $AdminUsername = "UserName" # Write the name of the administrator account in the new VM $Password = "Password"      # Write the password of the administrator account in the new VM $Image = "Copy the ImageName property you get from Get-AzureVMImage" # You can list your own images using the following command: # Get-AzureVMImage | Where-Object {$_.PublisherName -eq "User" }         New-AzureVMConfig -Name $VmName -ImageName $Image -InstanceSize $InstanceSize |             Add-AzureProvisioningConfig -Windows -Password $Password -AdminUsername $AdminUsername|             New-AzureVM -Location $Location -ServiceName "$VmName" -Verbose     } }   # Set the proper storage - you might remove this line if you have only one storage in the subscription Set-AzureSubscription -SubscriptionName $SubscriptionName -CurrentStorageAccount $StorageAccount   # Select the subscription - this line is fundamental if you have access to multiple subscription # You might remove this line if you have only one subscription Select-AzureSubscription -SubscriptionName $SubscriptionName   # Every line in the following list provisions one VM using the name specified in the argument # You can change the number of lines - use a unique name for every VM - don't reuse names # already used in other VMs already deployed ProvisionVM "test10" ProvisionVM "test11" ProvisionVM "test12" ProvisionVM "test13" ProvisionVM "test14" ProvisionVM "test15" ProvisionVM "test16" ProvisionVM "test17" ProvisionVM "test18" ProvisionVM "test19" ProvisionVM "test20"   # Wait for all to complete While (Get-Job -State "Running") {     Get-Job -State "Completed" | Receive-Job     Start-Sleep 1 }   # Display output from all jobs Get-Job | Receive-Job   # Cleanup of jobs Remove-Job *   # Displays batch completed echo "Provisioning VM Completed" RemoveVMs # Name of subscription $SubscriptionName = "Copy the SubscriptionName property you get from Get-AzureSubscription"   function RemoveVM( [string]$VmName ) {     Start-Job -ArgumentList $VmName {         param($VmName)         Remove-AzureService -ServiceName $VmName -Force -Verbose     } }   # Select the subscription - this line is fundamental if you have access to multiple subscription # You might remove this line if you have only one subscription Select-AzureSubscription -SubscriptionName $SubscriptionName   # Every line in the following list remove one VM using the name specified in the argument # You can change the number of lines - use a unique name for every VM - don't reuse names # already used in other VMs already deployed RemoveVM "test10" RemoveVM "test11" RemoveVM "test12" RemoveVM "test13" RemoveVM "test14" RemoveVM "test15" RemoveVM "test16" RemoveVM "test17" RemoveVM "test18" RemoveVM "test19" RemoveVM "test20"   # Wait for all to complete While (Get-Job -State "Running") {     Get-Job -State "Completed" | Receive-Job     Start-Sleep 1 }   # Display output from all jobs Get-Job | Receive-Job   # Cleanup Remove-Job *   # Displays batch completed echo "Remove VM Completed" StartVMs # Name of subscription $SubscriptionName = "Copy the SubscriptionName property you get from Get-AzureSubscription"   function StartVM( [string]$VmName ) {     Start-Job -ArgumentList $VmName {         param($VmName)         Start-AzureVM -Name $VmName -ServiceName $VmName -Verbose     } }   # Select the subscription - this line is fundamental if you have access to multiple subscription # You might remove this line if you have only one subscription Select-AzureSubscription -SubscriptionName $SubscriptionName   # Every line in the following list starts one VM using the name specified in the argument # You can change the number of lines - use a unique name for every VM - don't reuse names # already used in other VMs already deployed StartVM "test10" StartVM "test11" StartVM "test11" StartVM "test12" StartVM "test13" StartVM "test14" StartVM "test15" StartVM "test16" StartVM "test17" StartVM "test18" StartVM "test19" StartVM "test20"   # Wait for all to complete While (Get-Job -State "Running") {     Get-Job -State "Completed" | Receive-Job     Start-Sleep 1 }   # Display output from all jobs Get-Job | Receive-Job   # Cleanup Remove-Job *   # Displays batch completed echo "Start VM Completed"   StopVMs # Name of subscription $SubscriptionName = "Copy the SubscriptionName property you get from Get-AzureSubscription"   function StopVM( [string]$VmName ) {     Start-Job -ArgumentList $VmName {         param($VmName)         Stop-AzureVM -Name $VmName -ServiceName $VmName -Verbose -Force     } }   # Select the subscription - this line is fundamental if you have access to multiple subscription # You might remove this line if you have only one subscription Select-AzureSubscription -SubscriptionName $SubscriptionName   # Every line in the following list stops one VM using the name specified in the argument # You can change the number of lines - use a unique name for every VM - don't reuse names # already used in other VMs already deployed StopVM "test10" StopVM "test11" StopVM "test12" StopVM "test13" StopVM "test14" StopVM "test15" StopVM "test16" StopVM "test17" StopVM "test18" StopVM "test19" StopVM "test20"   # Wait for all to complete While (Get-Job -State "Running") {     Get-Job -State "Completed" | Receive-Job     Start-Sleep 1 }   # Display output from all jobs Get-Job | Receive-Job   # Cleanup Remove-Job *   # Displays batch completed echo "Stop VM Completed" RemoveOrphanDisks $Image = "Copy the ImageName property you get from Get-AzureVMImage" # You can list your own images using the following command: # Get-AzureVMImage | Where-Object {$_.PublisherName -eq "User" }   # Remove all orphan disks coming from the image specified in $ImageName Get-AzureDisk |     Where-Object {$_.attachedto -eq $null -and $_.SourceImageName -eq $ImageName} |     Remove-AzureDisk -DeleteVHD -Verbose  

    Read the article

  • SQL SERVER – Guest Posts – Feodor Georgiev – The Context of Our Database Environment – Going Beyond the Internal SQL Server Waits – Wait Type – Day 21 of 28

    - by pinaldave
    This guest post is submitted by Feodor. Feodor Georgiev is a SQL Server database specialist with extensive experience of thinking both within and outside the box. He has wide experience of different systems and solutions in the fields of architecture, scalability, performance, etc. Feodor has experience with SQL Server 2000 and later versions, and is certified in SQL Server 2008. In this article Feodor explains the server-client-server process, and concentrated on the mutual waits between client and SQL Server. This is essential in grasping the concept of waits in a ‘global’ application plan. Recently I was asked to write a blog post about the wait statistics in SQL Server and since I had been thinking about writing it for quite some time now, here it is. It is a wide-spread idea that the wait statistics in SQL Server will tell you everything about your performance. Well, almost. Or should I say – barely. The reason for this is that SQL Server is always a part of a bigger system – there are always other players in the game: whether it is a client application, web service, any other kind of data import/export process and so on. In short, the SQL Server surroundings look like this: This means that SQL Server, aside from its internal waits, also depends on external waits and settings. As we can see in the picture above, SQL Server needs to have an interface in order to communicate with the surrounding clients over the network. For this communication, SQL Server uses protocol interfaces. I will not go into detail about which protocols are best, but you can read this article. Also, review the information about the TDS (Tabular data stream). As we all know, our system is only as fast as its slowest component. This means that when we look at our environment as a whole, the SQL Server might be a victim of external pressure, no matter how well we have tuned our database server performance. Let’s dive into an example: let’s say that we have a web server, hosting a web application which is using data from our SQL Server, hosted on another server. The network card of the web server for some reason is malfunctioning (think of a hardware failure, driver failure, or just improper setup) and does not send/receive data faster than 10Mbs. On the other end, our SQL Server will not be able to send/receive data at a faster rate either. This means that the application users will notify the support team and will say: “My data is coming very slow.” Now, let’s move on to a bit more exciting example: imagine that there is a similar setup as the example above – one web server and one database server, and the application is not using any stored procedure calls, but instead for every user request the application is sending 80kb query over the network to the SQL Server. (I really thought this does not happen in real life until I saw it one day.) So, what happens in this case? To make things worse, let’s say that the 80kb query text is submitted from the application to the SQL Server at least 100 times per minute, and as often as 300 times per minute in peak times. Here is what happens: in order for this query to reach the SQL Server, it will have to be broken into a of number network packets (according to the packet size settings) – and will travel over the network. On the other side, our SQL Server network card will receive the packets, will pass them to our network layer, the packets will get assembled, and eventually SQL Server will start processing the query – parsing, allegorizing, generating the query execution plan and so on. So far, we have already had a serious network overhead by waiting for the packets to reach our Database Engine. There will certainly be some processing overhead – until the database engine deals with the 80kb query and its 20 subqueries. The waits you see in the DMVs are actually collected from the point the query reaches the SQL Server and the packets are assembled. Let’s say that our query is processed and it finally returns 15000 rows. These rows have a certain size as well, depending on the data types returned. This means that the data will have converted to packages (depending on the network size package settings) and will have to reach the application server. There will also be waits, however, this time you will be able to see a wait type in the DMVs called ASYNC_NETWORK_IO. What this wait type indicates is that the client is not consuming the data fast enough and the network buffers are filling up. Recently Pinal Dave posted a blog on Client Statistics. What Client Statistics does is captures the physical flow characteristics of the query between the client(Management Studio, in this case) and the server and back to the client. As you see in the image, there are three categories: Query Profile Statistics, Network Statistics and Time Statistics. Number of server roundtrips–a roundtrip consists of a request sent to the server and a reply from the server to the client. For example, if your query has three select statements, and they are separated by ‘GO’ command, then there will be three different roundtrips. TDS Packets sent from the client – TDS (tabular data stream) is the language which SQL Server speaks, and in order for applications to communicate with SQL Server, they need to pack the requests in TDS packets. TDS Packets sent from the client is the number of packets sent from the client; in case the request is large, then it may need more buffers, and eventually might even need more server roundtrips. TDS packets received from server –is the TDS packets sent by the server to the client during the query execution. Bytes sent from client – is the volume of the data set to our SQL Server, measured in bytes; i.e. how big of a query we have sent to the SQL Server. This is why it is best to use stored procedures, since the reusable code (which already exists as an object in the SQL Server) will only be called as a name of procedure + parameters, and this will minimize the network pressure. Bytes received from server – is the amount of data the SQL Server has sent to the client, measured in bytes. Depending on the number of rows and the datatypes involved, this number will vary. But still, think about the network load when you request data from SQL Server. Client processing time – is the amount of time spent in milliseconds between the first received response packet and the last received response packet by the client. Wait time on server replies – is the time in milliseconds between the last request packet which left the client and the first response packet which came back from the server to the client. Total execution time – is the sum of client processing time and wait time on server replies (the SQL Server internal processing time) Here is an illustration of the Client-server communication model which should help you understand the mutual waits in a client-server environment. Keep in mind that a query with a large ‘wait time on server replies’ means the server took a long time to produce the very first row. This is usual on queries that have operators that need the entire sub-query to evaluate before they proceed (for example, sort and top operators). However, a query with a very short ‘wait time on server replies’ means that the query was able to return the first row fast. However a long ‘client processing time’ does not necessarily imply the client spent a lot of time processing and the server was blocked waiting on the client. It can simply mean that the server continued to return rows from the result and this is how long it took until the very last row was returned. The bottom line is that developers and DBAs should work together and think carefully of the resource utilization in the client-server environment. From experience I can say that so far I have seen only cases when the application developers and the Database developers are on their own and do not ask questions about the other party’s world. I would recommend using the Client Statistics tool during new development to track the performance of the queries, and also to find a synchronous way of utilizing resources between the client – server – client. Here is another example: think about similar setup as above, but add another server to the game. Let’s say that we keep our media on a separate server, and together with the data from our SQL Server we need to display some images on the webpage requested by our user. No matter how simple or complicated the logic to get the images is, if the images are 500kb each our users will get the page slowly and they will still think that there is something wrong with our data. Anyway, I don’t mean to get carried away too far from SQL Server. Instead, what I would like to say is that DBAs should also be aware of ‘the big picture’. I wrote a blog post a while back on this topic, and if you are interested, you can read it here about the big picture. And finally, here are some guidelines for monitoring the network performance and improving it: Run a trace and outline all queries that return more than 1000 rows (in Profiler you can actually filter and sort the captured trace by number of returned rows). This is not a set number; it is more of a guideline. The general thought is that no application user can consume that many rows at once. Ask yourself and your fellow-developers: ‘why?’. Monitor your network counters in Perfmon: Network Interface:Output queue length, Redirector:Network errors/sec, TCPv4: Segments retransmitted/sec and so on. Make sure to establish a good friendship with your network administrator (buy them coffee, for example J ) and get into a conversation about the network settings. Have them explain to you how the network cards are setup – are they standalone, are they ‘teamed’, what are the settings – full duplex and so on. Find some time to read a bit about networking. In this short blog post I hope I have turned your attention to ‘the big picture’ and the fact that there are other factors affecting our SQL Server, aside from its internal workings. As a further reading I would still highly recommend the Wait Stats series on this blog, also I would recommend you have the coffee break conversation with your network admin as soon as possible. This guest post is written by Feodor Georgiev. Read all the post in the Wait Types and Queue series. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, Readers Contribution, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQL Wait Stats, SQL Wait Types, T SQL

    Read the article

  • Adventures in MVVM &ndash; My ViewModel Base

    - by Brian Genisio's House Of Bilz
    More Adventures in MVVM First, I’d like to say: THIS IS NOT A NEW MVVM FRAMEWORK. I tend to believe that MVVM support code should be specific to the system you are building and the developers working on it.  I have yet to find an MVVM framework that does everything I want it to without doing too much.  Don’t get me wrong… there are some good frameworks out there.  I just like to pick and choose things that make sense for me.  I’d also like to add that some of these features only work in WPF.  As of Silveright 4, they don’t support binding to dynamic properties, so some of the capabilities are lost. That being said, I want to share my ViewModel base class with the world.  I have had several conversations with people about the problems I have solved using this ViewModel base.  A while back, I posted an article about some experiments with a “Rails Inspired ViewModel”.  What followed from those ideas was a ViewModel base class that I take with me and use in my projects.  It has a lot of features, all designed to reduce the friction in writing view models. I have put the code out on Codeplex under the project: ViewModelSupport. Finally, this article focuses on the ViewModel and only glosses over the View and the Model.  Without all three, you don’t have MVVM.  But this base class is for the ViewModel, so that is what I am focusing on. Features: Automatic Command Plumbing Property Change Notification Strongly Typed Property Getter/Setters Dynamic Properties Default Property values Derived Properties Automatic Method Execution Command CanExecute Change Notification Design-Time Detection What about Silverlight? Automatic Command Plumbing This feature takes the plumbing out of creating commands.  The common pattern for commands in a ViewModel is to have an Execute method as well as an optional CanExecute method.  To plumb that together, you create an ICommand Property, and set it in the constructor like so: Before public class AutomaticCommandViewModel { public AutomaticCommandViewModel() { MyCommand = new DelegateCommand(Execute_MyCommand, CanExecute_MyCommand); } public void Execute_MyCommand() { // Do something } public bool CanExecute_MyCommand() { // Are we in a state to do something? return true; } public DelegateCommand MyCommand { get; private set; } } With the base class, this plumbing is automatic and the property (MyCommand of type ICommand) is created for you.  The base class uses the convention that methods be prefixed with Execute_ and CanExecute_ in order to be plumbed into commands with the property name after the prefix.  You are left to be expressive with your behavior without the plumbing.  If you are wondering how CanExecuteChanged is raised, see the later section “Command CanExecute Change Notification”. After public class AutomaticCommandViewModel : ViewModelBase { public void Execute_MyCommand() { // Do something } public bool CanExecute_MyCommand() { // Are we in a state to do something? return true; } }   Property Change Notification One thing that always kills me when implementing ViewModels is how to make properties that notify when they change (via the INotifyPropertyChanged interface).  There have been many attempts to make this more automatic.  My base class includes one option.  There are others, but I feel like this works best for me. The common pattern (without my base class) is to create a private backing store for the variable and specify a getter that returns the private field.  The setter will set the private field and fire an event that notifies the change, only if the value has changed. Before public class PropertyHelpersViewModel : INotifyPropertyChanged { private string text; public string Text { get { return text; } set { if(text != value) { text = value; RaisePropertyChanged("Text"); } } } protected void RaisePropertyChanged(string propertyName) { var handlers = PropertyChanged; if(handlers != null) handlers(this, new PropertyChangedEventArgs(propertyName)); } public event PropertyChangedEventHandler PropertyChanged; } This way of defining properties is error-prone and tedious.  Too much plumbing.  My base class eliminates much of that plumbing with the same functionality: After public class PropertyHelpersViewModel : ViewModelBase { public string Text { get { return Get<string>("Text"); } set { Set("Text", value);} } }   Strongly Typed Property Getters/Setters It turns out that we can do better than that.  We are using a strongly typed language where the use of “Magic Strings” is often frowned upon.  Lets make the names in the getters and setters strongly typed: A refinement public class PropertyHelpersViewModel : ViewModelBase { public string Text { get { return Get(() => Text); } set { Set(() => Text, value); } } }   Dynamic Properties In C# 4.0, we have the ability to program statically OR dynamically.  This base class lets us leverage the powerful dynamic capabilities in our ecosystem. (This is how the automatic commands are implemented, BTW)  By calling Set(“Foo”, 1), you have now created a dynamic property called Foo.  It can be bound against like any static property.  The opportunities are endless.  One great way to exploit this behavior is if you have a customizable view engine with templates that bind to properties defined by the user.  The base class just needs to create the dynamic properties at runtime from information in the model, and the custom template can bind even though the static properties do not exist. All dynamic properties still benefit from the notifiable capabilities that static properties do. For any nay-sayers out there that don’t like using the dynamic features of C#, just remember this: the act of binding the View to a ViewModel is dynamic already.  Why not exploit it?  Get over it :) Just declare the property dynamically public class DynamicPropertyViewModel : ViewModelBase { public DynamicPropertyViewModel() { Set("Foo", "Bar"); } } Then reference it normally <TextBlock Text="{Binding Foo}" />   Default Property Values The Get() method also allows for default properties to be set.  Don’t set them in the constructor.  Set them in the property and keep the related code together: public string Text { get { return Get(() => Text, "This is the default value"); } set { Set(() => Text, value);} }   Derived Properties This is something I blogged about a while back in more detail.  This feature came from the chaining of property notifications when one property affects the results of another, like this: Before public class DependantPropertiesViewModel : ViewModelBase { public double Score { get { return Get(() => Score); } set { Set(() => Score, value); RaisePropertyChanged("Percentage"); RaisePropertyChanged("Output"); } } public int Percentage { get { return (int)(100 * Score); } } public string Output { get { return "You scored " + Percentage + "%."; } } } The problem is: The setter for Score has to be responsible for notifying the world that Percentage and Output have also changed.  This, to me, is backwards.    It certainly violates the “Single Responsibility Principle.” I have been bitten in the rear more than once by problems created from code like this.  What we really want to do is invert the dependency.  Let the Percentage property declare that it changes when the Score Property changes. After public class DependantPropertiesViewModel : ViewModelBase { public double Score { get { return Get(() => Score); } set { Set(() => Score, value); } } [DependsUpon("Score")] public int Percentage { get { return (int)(100 * Score); } } [DependsUpon("Percentage")] public string Output { get { return "You scored " + Percentage + "%."; } } }   Automatic Method Execution This one is extremely similar to the previous, but it deals with method execution as opposed to property.  When you want to execute a method triggered by property changes, let the method declare the dependency instead of the other way around. Before public class DependantMethodsViewModel : ViewModelBase { public double Score { get { return Get(() => Score); } set { Set(() => Score, value); WhenScoreChanges(); } } public void WhenScoreChanges() { // Handle this case } } After public class DependantMethodsViewModel : ViewModelBase { public double Score { get { return Get(() => Score); } set { Set(() => Score, value); } } [DependsUpon("Score")] public void WhenScoreChanges() { // Handle this case } }   Command CanExecute Change Notification Back to Commands.  One of the responsibilities of commands that implement ICommand – it must fire an event declaring that CanExecute() needs to be re-evaluated.  I wanted to wait until we got past a few concepts before explaining this behavior.  You can use the same mechanism here to fire off the change.  In the CanExecute_ method, declare the property that it depends upon.  When that property changes, the command will fire a CanExecuteChanged event, telling the View to re-evaluate the state of the command.  The View will make appropriate adjustments, like disabling the button. DependsUpon works on CanExecute methods as well public class CanExecuteViewModel : ViewModelBase { public void Execute_MakeLower() { Output = Input.ToLower(); } [DependsUpon("Input")] public bool CanExecute_MakeLower() { return !string.IsNullOrWhiteSpace(Input); } public string Input { get { return Get(() => Input); } set { Set(() => Input, value);} } public string Output { get { return Get(() => Output); } set { Set(() => Output, value); } } }   Design-Time Detection If you want to add design-time data to your ViewModel, the base class has a property that lets you ask if you are in the designer.  You can then set some default values that let your designer see what things might look like in runtime. Use the IsInDesignMode property public DependantPropertiesViewModel() { if(IsInDesignMode) { Score = .5; } }   What About Silverlight? Some of the features in this base class only work in WPF.  As of version 4, Silverlight does not support binding to dynamic properties.  This, in my opinion, is a HUGE limitation.  Not only does it keep you from using many of the features in this ViewModel, it also keeps you from binding to ViewModels designed in IronRuby.  Does this mean that the base class will not work in Silverlight?  No.  Many of the features outlined in this article WILL work.  All of the property abstractions are functional, as long as you refer to them statically in the View.  This, of course, means that the automatic command hook-up doesn’t work in Silverlight.  You need to plumb it to a static property in order for the Silverlight View to bind to it.  Can I has a dynamic property in SL5?     Good to go? So, that concludes the feature explanation of my ViewModel base class.  Feel free to take it, fork it, whatever.  It is hosted on CodePlex.  When I find other useful additions, I will add them to the public repository.  I use this base class every day.  It is mature, and well tested.  If, however, you find any problems with it, please let me know!  Also, feel free to suggest patches to me via the CodePlex site.  :)

    Read the article

  • SQL SERVER – Guest Post – Jonathan Kehayias – Wait Type – Day 16 of 28

    - by pinaldave
    Jonathan Kehayias (Blog | Twitter) is a MCITP Database Administrator and Developer, who got started in SQL Server in 2004 as a database developer and report writer in the natural gas industry. After spending two and a half years working in TSQL, in late 2006, he transitioned to the role of SQL Database Administrator. His primary passion is performance tuning, where he frequently rewrites queries for better performance and performs in depth analysis of index implementation and usage. Jonathan blogs regularly on SQLBlog, and was a coauthor of Professional SQL Server 2008 Internals and Troubleshooting. On a personal note, I think Jonathan is extremely positive person. In every conversation with him I have found that he is always eager to help and encourage. Every time he finds something needs to be approved, he has contacted me without hesitation and guided me to improve, change and learn. During all the time, he has not lost his focus to help larger community. I am honored that he has accepted to provide his views on complex subject of Wait Types and Queues. Currently I am reading his series on Extended Events. Here is the guest blog post by Jonathan: SQL Server troubleshooting is all about correlating related pieces of information together to indentify where exactly the root cause of a problem lies. In my daily work as a DBA, I generally get phone calls like, “So and so application is slow, what’s wrong with the SQL Server.” One of the funny things about the letters DBA is that they go so well with Default Blame Acceptor, and I really wish that I knew exactly who the first person was that pointed that out to me, because it really fits at times. A lot of times when I get this call, the problem isn’t related to SQL Server at all, but every now and then in my initial quick checks, something pops up that makes me start looking at things further. The SQL Server is slow, we see a number of tasks waiting on ASYNC_IO_COMPLETION, IO_COMPLETION, or PAGEIOLATCH_* waits in sys.dm_exec_requests and sys.dm_exec_waiting_tasks. These are also some of the highest wait types in sys.dm_os_wait_stats for the server, so it would appear that we have a disk I/O bottleneck on the machine. A quick check of sys.dm_io_virtual_file_stats() and tempdb shows a high write stall rate, while our user databases show high read stall rates on the data files. A quick check of some performance counters and Page Life Expectancy on the server is bouncing up and down in the 50-150 range, the Free Page counter consistently hits zero, and the Free List Stalls/sec counter keeps jumping over 10, but Buffer Cache Hit Ratio is 98-99%. Where exactly is the problem? In this case, which happens to be based on a real scenario I faced a few years back, the problem may not be a disk bottleneck at all; it may very well be a memory pressure issue on the server. A quick check of the system spec’s and it is a dual duo core server with 8GB RAM running SQL Server 2005 SP1 x64 on Windows Server 2003 R2 x64. Max Server memory is configured at 6GB and we think that this should be enough to handle the workload; or is it? This is a unique scenario because there are a couple of things happening inside of this system, and they all relate to what the root cause of the performance problem is on the system. If we were to query sys.dm_exec_query_stats for the TOP 10 queries, by max_physical_reads, max_logical_reads, and max_worker_time, we may be able to find some queries that were using excessive I/O and possibly CPU against the system in their worst single execution. We can also CROSS APPLY to sys.dm_exec_sql_text() and see the statement text, and also CROSS APPLY sys.dm_exec_query_plan() to get the execution plan stored in cache. Ok, quick check, the plans are pretty big, I see some large index seeks, that estimate 2.8GB of data movement between operators, but everything looks like it is optimized the best it can be. Nothing really stands out in the code, and the indexing looks correct, and I should have enough memory to handle this in cache, so it must be a disk I/O problem right? Not exactly! If we were to look at how much memory the plan cache is taking by querying sys.dm_os_memory_clerks for the CACHESTORE_SQLCP and CACHESTORE_OBJCP clerks we might be surprised at what we find. In SQL Server 2005 RTM and SP1, the plan cache was allowed to take up to 75% of the memory under 8GB. I’ll give you a second to go back and read that again. Yes, you read it correctly, it says 75% of the memory under 8GB, but you don’t have to take my word for it, you can validate this by reading Changes in Caching Behavior between SQL Server 2000, SQL Server 2005 RTM and SQL Server 2005 SP2. In this scenario the application uses an entirely adhoc workload against SQL Server and this leads to plan cache bloat, and up to 4.5GB of our 6GB of memory for SQL can be consumed by the plan cache in SQL Server 2005 SP1. This in turn reduces the size of the buffer cache to just 1.5GB, causing our 2.8GB of data movement in this expensive plan to cause complete flushing of the buffer cache, not just once initially, but then another time during the queries execution, resulting in excessive physical I/O from disk. Keep in mind that this is not the only query executing at the time this occurs. Remember the output of sys.dm_io_virtual_file_stats() showed high read stalls on the data files for our user databases versus higher write stalls for tempdb? The memory pressure is also forcing heavier use of tempdb to handle sorting and hashing in the environment as well. The real clue here is the Memory counters for the instance; Page Life Expectancy, Free List Pages, and Free List Stalls/sec. The fact that Page Life Expectancy is fluctuating between 50 and 150 constantly is a sign that the buffer cache is experiencing constant churn of data, once every minute to two and a half minutes. If you add to the Page Life Expectancy counter, the consistent bottoming out of Free List Pages along with Free List Stalls/sec consistently spiking over 10, and you have the perfect memory pressure scenario. All of sudden it may not be that our disk subsystem is the problem, but is instead an innocent bystander and victim. Side Note: The Page Life Expectancy counter dropping briefly and then returning to normal operating values intermittently is not necessarily a sign that the server is under memory pressure. The Books Online and a number of other references will tell you that this counter should remain on average above 300 which is the time in seconds a page will remain in cache before being flushed or aged out. This number, which equates to just five minutes, is incredibly low for modern systems and most published documents pre-date the predominance of 64 bit computing and easy availability to larger amounts of memory in SQL Servers. As food for thought, consider that my personal laptop has more memory in it than most SQL Servers did at the time those numbers were posted. I would argue that today, a system churning the buffer cache every five minutes is in need of some serious tuning or a hardware upgrade. Back to our problem and its investigation: There are two things really wrong with this server; first the plan cache is excessively consuming memory and bloated in size and we need to look at that and second we need to evaluate upgrading the memory to accommodate the workload being performed. In the case of the server I was working on there were a lot of single use plans found in sys.dm_exec_cached_plans (where usecounts=1). Single use plans waste space in the plan cache, especially when they are adhoc plans for statements that had concatenated filter criteria that is not likely to reoccur with any frequency.  SQL Server 2005 doesn’t natively have a way to evict a single plan from cache like SQL Server 2008 does, but MVP Kalen Delaney, showed a hack to evict a single plan by creating a plan guide for the statement and then dropping that plan guide in her blog post Geek City: Clearing a Single Plan from Cache. We could put that hack in place in a job to automate cleaning out all the single use plans periodically, minimizing the size of the plan cache, but a better solution would be to fix the application so that it uses proper parameterized calls to the database. You didn’t write the app, and you can’t change its design? Ok, well you could try to force parameterization to occur by creating and keeping plan guides in place, or we can try forcing parameterization at the database level by using ALTER DATABASE <dbname> SET PARAMETERIZATION FORCED and that might help. If neither of these help, we could periodically dump the plan cache for that database, as discussed as being a problem in Kalen’s blog post referenced above; not an ideal scenario. The other option is to increase the memory on the server to 16GB or 32GB, if the hardware allows it, which will increase the size of the plan cache as well as the buffer cache. In SQL Server 2005 SP1, on a system with 16GB of memory, if we set max server memory to 14GB the plan cache could use at most 9GB  [(8GB*.75)+(6GB*.5)=(6+3)=9GB], leaving 5GB for the buffer cache.  If we went to 32GB of memory and set max server memory to 28GB, the plan cache could use at most 16GB [(8*.75)+(20*.5)=(6+10)=16GB], leaving 12GB for the buffer cache. Thankfully we have SQL Server 2005 Service Pack 2, 3, and 4 these days which include the changes in plan cache sizing discussed in the Changes to Caching Behavior between SQL Server 2000, SQL Server 2005 RTM and SQL Server 2005 SP2 blog post. In real life, when I was troubleshooting this problem, I spent a week trying to chase down the cause of the disk I/O bottleneck with our Server Admin and SAN Admin, and there wasn’t much that could be done immediately there, so I finally asked if we could increase the memory on the server to 16GB, which did fix the problem. It wasn’t until I had this same problem occur on another system that I actually figured out how to really troubleshoot this down to the root cause.  I couldn’t believe the size of the plan cache on the server with 16GB of memory when I actually learned about this and went back to look at it. SQL Server is constantly telling a story to anyone that will listen. As the DBA, you have to sit back and listen to all that it’s telling you and then evaluate the big picture and how all the data you can gather from SQL about performance relate to each other. One of the greatest tools out there is actually a free in the form of Diagnostic Scripts for SQL Server 2005 and 2008, created by MVP Glenn Alan Berry. Glenn’s scripts collect a majority of the information that SQL has to offer for rapid troubleshooting of problems, and he includes a lot of notes about what the outputs of each individual query might be telling you. When I read Pinal’s blog post SQL SERVER – ASYNC_IO_COMPLETION – Wait Type – Day 11 of 28, I noticed that he referenced Checking Memory Related Performance Counters in his post, but there was no real explanation about why checking memory counters is so important when looking at an I/O related wait type. I thought I’d chat with him briefly on Google Talk/Twitter DM and point this out, and offer a couple of other points I noted, so that he could add the information to his blog post if he found it useful.  Instead he asked that I write a guest blog for this. I am honored to be a guest blogger, and to be able to share this kind of information with the community. The information contained in this blog post is a glimpse at how I do troubleshooting almost every day of the week in my own environment. SQL Server provides us with a lot of information about how it is running, and where it may be having problems, it is up to us to play detective and find out how all that information comes together to tell us what’s really the problem. This blog post is written by Jonathan Kehayias (Blog | Twitter). Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: MVP, Pinal Dave, PostADay, Readers Contribution, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQL Wait Stats, SQL Wait Types, T SQL, Technology

    Read the article

  • Performance Optimization &ndash; It Is Faster When You Can Measure It

    - by Alois Kraus
    Performance optimization in bigger systems is hard because the measured numbers can vary greatly depending on the measurement method of your choice. To measure execution timing of specific methods in your application you usually use Time Measurement Method Potential Pitfalls Stopwatch Most accurate method on recent processors. Internally it uses the RDTSC instruction. Since the counter is processor specific you can get greatly different values when your thread is scheduled to another core or the core goes into a power saving mode. But things do change luckily: Intel's Designer's vol3b, section 16.11.1 "16.11.1 Invariant TSC The time stamp counter in newer processors may support an enhancement, referred to as invariant TSC. Processor's support for invariant TSC is indicated by CPUID.80000007H:EDX[8]. The invariant TSC will run at a constant rate in all ACPI P-, C-. and T-states. This is the architectural behavior moving forward. On processors with invariant TSC support, the OS may use the TSC for wall clock timer services (instead of ACPI or HPET timers). TSC reads are much more efficient and do not incur the overhead associated with a ring transition or access to a platform resource." DateTime.Now Good but it has only a resolution of 16ms which can be not enough if you want more accuracy.   Reporting Method Potential Pitfalls Console.WriteLine Ok if not called too often. Debug.Print Are you really measuring performance with Debug Builds? Shame on you. Trace.WriteLine Better but you need to plug in some good output listener like a trace file. But be aware that the first time you call this method it will read your app.config and deserialize your system.diagnostics section which does also take time.   In general it is a good idea to use some tracing library which does measure the timing for you and you only need to decorate some methods with tracing so you can later verify if something has changed for the better or worse. In my previous article I did compare measuring performance with quantum mechanics. This analogy does work surprising well. When you measure a quantum system there is a lower limit how accurately you can measure something. The Heisenberg uncertainty relation does tell us that you cannot measure of a quantum system the impulse and location of a particle at the same time with infinite accuracy. For programmers the two variables are execution time and memory allocations. If you try to measure the timings of all methods in your application you will need to store them somewhere. The fastest storage space besides the CPU cache is the memory. But if your timing values do consume all available memory there is no memory left for the actual application to run. On the other hand if you try to record all memory allocations of your application you will also need to store the data somewhere. This will cost you memory and execution time. These constraints are always there and regardless how good the marketing of tool vendors for performance and memory profilers are: Any measurement will disturb the system in a non predictable way. Commercial tool vendors will tell you they do calculate this overhead and subtract it from the measured values to give you the most accurate values but in reality it is not entirely true. After falling into the trap to trust the profiler timings several times I have got into the habit to Measure with a profiler to get an idea where potential bottlenecks are. Measure again with tracing only the specific methods to check if this method is really worth optimizing. Optimize it Measure again. Be surprised that your optimization has made things worse. Think harder Implement something that really works. Measure again Finished! - Or look for the next bottleneck. Recently I have looked into issues with serialization performance. For serialization DataContractSerializer was used and I was not sure if XML is really the most optimal wire format. After looking around I have found protobuf-net which uses Googles Protocol Buffer format which is a compact binary serialization format. What is good for Google should be good for us. A small sample app to check out performance was a matter of minutes: using ProtoBuf; using System; using System.Diagnostics; using System.IO; using System.Reflection; using System.Runtime.Serialization; [DataContract, Serializable] class Data { [DataMember(Order=1)] public int IntValue { get; set; } [DataMember(Order = 2)] public string StringValue { get; set; } [DataMember(Order = 3)] public bool IsActivated { get; set; } [DataMember(Order = 4)] public BindingFlags Flags { get; set; } } class Program { static MemoryStream _Stream = new MemoryStream(); static MemoryStream Stream { get { _Stream.Position = 0; _Stream.SetLength(0); return _Stream; } } static void Main(string[] args) { DataContractSerializer ser = new DataContractSerializer(typeof(Data)); Data data = new Data { IntValue = 100, IsActivated = true, StringValue = "Hi this is a small string value to check if serialization does work as expected" }; var sw = Stopwatch.StartNew(); int Runs = 1000 * 1000; for (int i = 0; i < Runs; i++) { //ser.WriteObject(Stream, data); Serializer.Serialize<Data>(Stream, data); } sw.Stop(); Console.WriteLine("Did take {0:N0}ms for {1:N0} objects", sw.Elapsed.TotalMilliseconds, Runs); Console.ReadLine(); } } The results are indeed promising: Serializer Time in ms N objects protobuf-net   807 1000000 DataContract 4402 1000000 Nearly a factor 5 faster and a much more compact wire format. Lets use it! After switching over to protbuf-net the transfered wire data has dropped by a factor two (good) and the performance has worsened by nearly a factor two. How is that possible? We have measured it? Protobuf-net is much faster! As it turns out protobuf-net is faster but it has a cost: For the first time a type is de/serialized it does use some very smart code-gen which does not come for free. Lets try to measure this one by setting of our performance test app the Runs value not to one million but to 1. Serializer Time in ms N objects protobuf-net 85 1 DataContract 24 1 The code-gen overhead is significant and can take up to 200ms for more complex types. The break even point where the code-gen cost is amortized by its faster serialization performance is (assuming small objects) somewhere between 20.000-40.000 serialized objects. As it turned out my specific scenario involved about 100 types and 1000 serializations in total. That explains why the good old DataContractSerializer is not so easy to take out of business. The final approach I ended up was to reduce the number of types and to serialize primitive types via BinaryWriter directly which turned out to be a pretty good alternative. It sounded good until I measured again and found that my optimizations so far do not help much. After looking more deeper at the profiling data I did found that one of the 1000 calls did take 50% of the time. So how do I find out which call it was? Normal profilers do fail short at this discipline. A (totally undeserved) relatively unknown profiler is SpeedTrace which does unlike normal profilers create traces of your applications by instrumenting your IL code at runtime. This way you can look at the full call stack of the one slow serializer call to find out if this stack was something special. Unfortunately the call stack showed nothing special. But luckily I have my own tracing as well and I could see that the slow serializer call did happen during the serialization of a bool value. When you encounter after much analysis something unreasonable you cannot explain it then the chances are good that your thread was suspended by the garbage collector. If there is a problem with excessive GCs remains to be investigated but so far the serialization performance seems to be mostly ok.  When you do profile a complex system with many interconnected processes you can never be sure that the timings you just did measure are accurate at all. Some process might be hitting the disc slowing things down for all other processes for some seconds as well. There is a big difference between warm and cold startup. If you restart all processes you can basically forget the first run because of the OS disc cache, JIT and GCs make the measured timings very flexible. When you are in need of a random number generator you should measure cold startup times of a sufficiently complex system. After the first run you can try again getting different and much lower numbers. Now try again at least two times to get some feeling how stable the numbers are. Oh and try to do the same thing the next day. It might be that the bottleneck you found yesterday is gone today. Thanks to GC and other random stuff it can become pretty hard to find stuff worth optimizing if no big bottlenecks except bloatloads of code are left anymore. When I have found a spot worth optimizing I do make the code changes and do measure again to check if something has changed. If it has got slower and I am certain that my change should have made it faster I can blame the GC again. The thing is that if you optimize stuff and you allocate less objects the GC times will shift to some other location. If you are unlucky it will make your faster working code slower because you see now GCs at times where none were before. This is where the stuff does get really tricky. A safe escape hatch is to create a repro of the slow code in an isolated application so you can change things fast in a reliable manner. Then the normal profilers do also start working again. As Vance Morrison does point out it is much more complex to profile a system against the wall clock compared to optimize for CPU time. The reason is that for wall clock time analysis you need to understand how your system does work and which threads (if you have not one but perhaps 20) are causing a visible delay to the end user and which threads can wait a long time without affecting the user experience at all. Next time: Commercial profiler shootout.

    Read the article

  • Weblogic domain scale up using EM Grid Control 11gR1

    - by dmitry.nefedkin(at)oracle.com
    As you know a weblogic domain consists of set of servers running independently or in a cluster mode, sharing the distributed resources. And in most environments weblogic  cluster consists of multiple managed servers running simultaneously and working together to provide increased scalability and reliability.  These servers can run on the same machine, or be located on different machines.  It's a common task to increase a cluster's capacity by adding new machines to the cluster to host the new server instances.  You can do it by manually installing weblogic binaries to the new host and use pack/unpack commands to add a managed server to this new host.  But with Enterprise Manager Grid Control 11gR1 (EMGC) there is  another way - Fusion Middleware Domain Scale Up  procedure. I'm going to show you how it works.Here is a picture of  my medrec_oradb weblogic domain, what is registered in EMGC. It contains an admin server and a cluster MedRecCluster with  the single managed server MS1. Both admin and managed servers are on the same host oel46-vmware, it's a virtual machine with OEL 4.6 that runs inside our Oracle VM infrastructure.  And here are the application deployments, note that couple of applications are deployed to the cluster.First of all I have to prepare a new machine that will host new managed sever of my cluster. I created new VM with OEL 5.4 using the corresponding Oracle VM template available in Oracle E-Delivery site for Oracle Linux and Oracle VM and named it wls1032. Next step is to install Oracle EM Grid Control 11gR1 Agent to this new host.  You can download it from the OTN page and install it manually,  or you can use Agent Installation Deployment procedure available in EMGC  (Deployments->Agent Installation->Install Agent). Anyway, when you agent is up and running on the new machine, you will see it in EMGC Console in the Targets->Hosts subtab.Now we are ready to scale up our weblogic domain. Click the Deployments tab in Oracle Enterprise Manager Grid Control, and then click Deployment Procedure. Select a Fusion Middleware Domain Scale Up procedure from the list, and click Schedule Deployment. The first page of the FMW Domain Scale Up Wizard is displayed and you can proceed with the deployment process.Select the domain from list, enter the working directory on the admin server host, and also fill the weblogic credentials for the administration server console and the OS credentials for the  admin server host.  Click Next button.  The next step allows you to configure you domain, to add a new manager server to the cluster you should select the cluster in the tree and click Add Server button. Select the newly added server in a tree, choose the target host and  enter the configuration details of your managed server. You can also add new machine and node manager details.  Please note that you cannot change the values in  Domain Location and Fusion Middleware Home fields, so these locations on the target host will be the same as for the admin server host.   Working directory on the target host should have enough free space to store FMW home binaries and domain configuration files.  In my experience the working directories should have at least 3 Gb of free space.  The last thing you should fill is the OS credentials for the target host. The next steps allows you to schedule the execution of the procedure, it is started immediately in my example. The last step is just a review the configuration for the domain scale up. Click Submit to launch the process. You can track the status of the procedure execution by selecting Deployments->Deployment Procedures->Procedure Completion Status in the EMGC Console.As you can see in the picture below, the procedure consists of the many steps, and I'm going to share my experience about the issues that I had at some of the steps. Please keep in mind that you can always continue the execution from the last successfully completed step by clicking Retry button.Check OUI Prerequisites  step may fail if the target host does  not pass prerequisites checks for Weblogic Server installation such as amount of RAM, linux packages installed, etc. Create FMW Clone Archive step may fail if you do not have enough free space in the working directory on the administration server host.Transfer cloning archive to targets  step  may fail if the EMGC agents on the admin server host or on target host are not secured.   You should secure the agent by issuing ./emctl secure agent  command from $AGENT_HOME/bin directory and entering the agent registration password.Both Transfer cloning archive to targets and Apply Clone at target hosts steps may fail if you do not have enough free space in the working directory on the target host. The most complicated issue I had on the Run Inventory Collection  step. The step failed and I noticed that the agent on the target server is also failed with the following error in the $AGENT_HOME/sysman/log/emagent.trc  log file:2010-12-28 11:50:34,310 Thread-2838952848 ERROR upload: Failed to upload file A0000008.xml: Fatal Error.Response received: 500|ORA-20603: The timezone of the multiagent target (/Farm_Localhost_MedRec_medrec_oradb/medrec_oradb,weblogic_domain)is not consistent with the timezone (America/Los_Angeles) reported by other agents.2010-12-28 11:50:34,310 Thread-2838952848 ERROR upload: 1 Failure(s) in a row or XML error for A0000008.xml, retcode = -6, we give up2010-12-28 11:50:35,552 Thread-2838952848 WARN  upload: FxferSend: received fatal error in header from repository: https://oel46-vmware:1159/em/uploadFATAL_ERROR::500|ORA-20603: The timezone of the multiagent target (/Farm_Localhost_MedRec_medrec_oradb/medrec_oradb,weblogic_domain)is not consistent with the timezone (America/Los_Angeles) reported by other agents.2010-12-28 11:50:35,552 Thread-2838952848 ERROR upload: number of fatal error exceeds the limit 32010-12-28 11:50:35,552 Thread-2838952848 ERROR upload: agent will shutdown now2010-12-28 11:50:35,552 Thread-2838952848 ERROR : Signalled to Exit with status 55. Too many fatal upload failures2010-12-28 11:50:35,552 Thread-2838952848 ERROR upload: 1 Failure(s) in a row or XML error for A0000008.xml, retcode = -6, we give up2010-12-28 11:50:35,552 Thread-3044607680 ERROR main: EMAgent abnormal terminatingI checked the timezone of my domain target inside EMGC repositoryselect timezone_regionfrom mgmt_targets where target_type = 'weblogic_domain'  and display_name = 'medrec_oradb'"TIMEZONE_REGION""America/Los_Angeles"Then checked the timezone of my agents and indeed, they differedselect target_name, timezone_region from mgmt_targets where type_display_name = 'Agent'"TARGET_NAME"    "TIMEZONE_REGION""oel46-vmware:3872"    "America/Los_Angeles""wls1032.imc.fors.ru:3872"    "America/New_York"So I had to change the timezone on the wls1032 host and propagate this changes to the agent and to the EMGC repository. Here was the steps:issued system-config-date command on wls1032.imc.fors.ru  and set timezone to "America/Los_Angeles"propagated the changes to the agent bu executing ./emctl resetTZ agent  command from $AGENT_HOME/bin directoryconnected to EMGC repository as sysman and executed the following PL/SQL block:   begin      mgmt_target.set_agent_tzrgn('wls1032.imc.fors.ru:3872','America/Los_Angeles');      commit;   end;After that I had to clear the pending uploads on wls1032.imc.fors.ru:  rm -r $AGENT_HOME/sysman/emd/state/*  rm -r $AGENT_HOME/sysman/emd/collection/*  rm -r $AGENT_HOME/sysman/emd/upload/*  rm $AGENT_HOME/sysman/emd/lastupld.xml  rm $AGENT_HOME/sysman/emd/agntstmp.txt  $AGENT_HOME/bin/emctl start agent  $AGENT_HOME/bin/emctl clearstate agentThe last part of this solution was to resync the agent in EMGC console by clicking Agent Resynchronization button (please leave "Unblock agent on successful completion of agent resynchronization" checkbox checked in the next screen).After that I issued ./emctl upload command from $AGENT_HOME/bin on the wls1032 host,  and my previous error disappeared,  but I catched another one: EMD upload error: Failed to upload file A0000004.xml: HTTP error.Response received: ERROR-400|Data will be rejected for upload from agent 'https://wls1032.imc.fors.ru:3872/emd/main/', max size limit for direct load exceeded [7544731/5242880]So the uploading XML file size was 7 Mb, and the limit on OMS was 5 Mb.  To increase the max file size limit to 20 Mb I had to connect to the OMS host and execute the following commands from $OMS_HOME/bin directory: ./emctl set property -name em.loader.maxDirectLoadFileSz -value 20971520 -module emoms ./emctl stop oms ./emctl start omsAfter that I issued ./emctl upload command from $AGENT_HOME/bin on the wls1032 one more time and it completed successfully.   The agent uploaded the configuration information to the EMGC  repository and I was able to see the results of my weblogic domain scale-up in EMGC Console.DeploymentsSo, now the weblogic cluster contains 2 managed servers located on the different hosts. This powerful feature of the Enterprise Manager Grid Control  is a part of  the WebLogic Server Management Pack Enterprise Edition.

    Read the article

  • CodePlex Daily Summary for Wednesday, June 11, 2014

    CodePlex Daily Summary for Wednesday, June 11, 2014Popular Releasescrashme: crashme 2.8.4 for 64 bit Windows: This release has new functionality that makes crashme potent in 64-bit processor architectures. This potency has been generally absent for several years, ever since Data Execution Prevention (DEP) became the default setting in most operating systems. After installation the TEST1.BAT short-cut will produce CRASHME-TEST1-MT.LOG containing the following process fatal exit exceptions after a 30-second run: EXCEPTION_SINGLE_STEP EXCEPTION_FLT_OVERFLOW EXCEPTION_DATATYPE_MISALIGNMENT EXCEPT...Random Execute: Random Execute Alpha Release: This release is the Alpha Release and more functionality to come based upon your feedback. Thanks!Bango Payment Flow in-app payments: Bango Payment Flow in-app payments example app: Sample application that uses the Bango Payment Flow SDKEssence#: Ark-2: The Ark-2 release provides fixes for bugs and for increased stability and robustness. It also features significant performance improvements. The only directly-visible difference is that the optional "Script run time" timing report no longer includes the time to setup and run the compiler, so it's a pure benchmark of the time required to actually execute a script.VidCoder: 1.5.23 Beta: Added first translations for 1.5. Includes new languages Portuguese, Japanese, Chinese Simplified and Czech. Many of these translations are still incomplete: you can help out on Crowdin. Added an option to pass through an input track if it matches the output codec. Updated HandBrake core to SVN 6209. Fixed crash on AAC passthrough. Fixed x264 settings getting set incorrectly when reverting from a preset with the Advanced tab. Fixed occasional crash when calculating remaining time. ...Bills Manager: Bills Manager (32227): New stable releasePowerShell App Deployment Toolkit: PowerShell App Deployment Toolkit v3.1.4: Added New-Folder and Remove-Folder functions (Thanks to SueH) Added NoWait parameter to Execute-Process Added the ability for Deploy-Application.exe to point to a different .ps1 file by specifying it on the command-line Added checks to Deploy-Application.exe to verify the AppDeployToolkit folder exists Added PSAppDeployToolkit icon to Deploy-Application.exe Fixed issue where hang could occur if file version was null when using Get-FileVersion Improved exception handling and loggin...Three-Dimensional Maneuver Gear for Minecraft: TDMG 1.1.1.1 for 1.7.2: 1.7.2??? ?????????ID?????? ?????jar?????CS-Script Source: Release v3.8.1: Improved ConfigConsole AdvancedShell extensions support cs-script.7z - CS-Script Suite (binaries, documentation, samples) cs-script.ExtensionPack.7z - CS-Script Extension Pack (additional binaries and samples) cs-scriptDocs.7z - CS-Script DocumentationPapercut: Papercut v3.0.0.0: Papercut has switched to semantic versioning! That means you will have to uninstall old "clickonce" versions to get the latest as it will see it as an older version. Latest Has Tons of New Features: Modern UI MVVM Architecture Watch Directories for New Messages Optional Backend Papercut Service Load on Windows Startup Attachments/Mime SectionsExperfwiz (Exchange Performance Data Collection tool): Experfwiz 1.3.8: List of updates in 1.3.8 Added support for Windows 2012 & 2012 R2 (for future use) Added support for Exchange 2013 Full is now enabled by default. To disable full mode, use 'nofull'. Exchange 2013 requires full. Added "\Processor Information()\" counters to Exchange 2010 full Blocked Exmon execution on Exchange 2013BugNET Issue Tracker: BugNET 1.6: Version 1.6 is a major upgrade to the latest frameworks and components by Microsoft. It includes a major UI overhaul using the bootstrap framework to have a modern, mobile friendly and easily customized layout. Upgrade to .NET 4.5 ASP.NET social auth Add script bundling and optimization Improvements for mobile devices Bootstrap (UI overhaul) Rewritten / friendly URL's Please read our release notes for BugNET 1.6: http://blog.bugnetproject.com/2014/06/08/bugnet-1-6-and-bugnet-pro-1...SFDL.NET: SFDL.NET (2.2.9.3): Changelog: Retry Bugfix (Error Counter wurde nicht korrekt zurückgesetzt) Neue Einstellung: Retry Wartezeit ist nun Einstellbarbabelua: 1.5.7.0: V1.5.7.0 - 2014.6.6Stability improvement: use "lua scripts folder" as lua search path when debugging;SEToolbox: SEToolbox 01.033.007 Release 1: Fixed breaking changes in Space Engineers in latest update. Installation of this version will replace older version.Virto Commerce Enterprise Open Source eCommerce Platform (asp.net mvc): Virto Commerce 1.10: Virto Commerce Community Edition version 1.10. To install the SDK package, please refer to SDK getting started documentation To configure source code package, please refer to Source code getting started documentation This release includes bug fixes and improvements (including Commerce Manager localization and https support). More details about this release can be found on our blog at http://blog.virtocommerce.com.NPOI: NPOI 2.1: Assembly Version: 2.1.0 New Features a. XSSFSheet.CopySheet b. Excel2Html for XSSF c. insert picture in word 2007 d. Implement IfError function in formula engine Bug Fixes a. fix conditional formatting issue b. fix ctFont order issue c. fix vertical alignment issue in XSSF d. add IndexedColors to NPOI.SS.UserModel e. fix decimal point issue in non-English culture f. fix SetMargin issue in XSSF g.fix multiple images insert issue in XSSF h.fix rich text style missing issue in XSSF i. fix cell...51Degrees - Device Detection and Redirection: 3.1.2.3: Version 3.1 HighlightsDevice detection algorithm is over 100 times faster. Regular expressions and levenshtein distance calculations are no longer used. The device detection algorithm performance is no longer limited by the number of device combinations contained in the dataset. Two modes of operation are available: Memory – the detection data set is loaded into memory and there is no continuous connection to the source data file. Slower initialisation time but faster detection performanc...CS-Script for Notepad++ (C# intellisense and code execution): Release v1.0.27.0: CodeMap now indicates the type name for all members Implemented running scripts 'as administrator'. Just add '//css_npp asadmin' to the script and run it as usual. 'Prepare script for distribution' now aggregates script dependency assemblies. Various improvements in CodeSnipptet, Autcompletion and MethodInfo interactions with each other. Added printing line number for the entries in CodeMap (subject of configuration value) Improved debugging step indication for classless scripts ...ClosedXML - The easy way to OpenXML: ClosedXML 0.72.3: 70426e13c415 ClosedXML for .Net 4.0 now uses Open XML SDK 2.5 b9ef53a6654f Merge branch 'master' of https://git01.codeplex.com/forks/vbjay/closedxml 727714e86416 Fix range.Merge(Boolean) for .Net 3.5 eb1ed478e50e Make public range.Merge(Boolean checkIntersects) 6284cf3c3991 More performance improvements when saving.New ProjectsAge of Visual: Proyecto que representa un juego de estrategiaAliexpress: Aliexpress Bell Open Imaging package: Bell Imaging package is an advanced and open source imaging libary. You can use it's code or various actions of editing, viewing and processing images.BizTalk Benchmark Analyzer: Benchmark any application and analyze the results to enable a better result when performance optimizing your solution.CheckName: This is a CheckNameDelsjömotet: Code for Windows Phone 8 application that will tell commuters of Västtrafik the next trip from and to Delsjömotet outside Gothenburg.EasyTest: This is a Webdriver Framework for creating enterprise level UI test suites. FIM Workflow Library: The FIM Workflow Library is a collection of custom FIM workflow activitiesjwkjReport: jwkjReport DesingerLF3Proj: project for lf OLEDB Wrapper for Excel and Textfiles: this project is for accessing excel and write values in excel it is just a wrapper for accessing excel using SQLPoshAsyncJob: Provides an alternative to PSjobs with greater performance and less overhead to run commands in the background, freeing up the console.proxydelivery: my proxy deliverySlingshot: Pending...Speech Synthesizer Bee .NetMF Driver: ????????Speech Synthesizer Bee???????.net micro framework???????; ??SYN6288????????; ???????netduino plus 2,?????.net micro frame??????-??????【??】: ?????????????????,??????????、??????,??????????、????、????、???????。?????-?????【??】: ?????????????????????,????????,??????????,?????,????? ,????????!?????-?????【??】: ?????????????????????,???????????????,???????,?????,?????,????? !!!??????-??????【??】: ????????????????、????、????、??????、????、????????,????????、?????????,?????。??????-??????【??】: ?????????????????,?????????????。????????????,???????,???????,?????,?????。????-????【??】: ????????????????:?????? ???? ??????,???????,??????,???????。?????-?????【??】: ???????????,????,??????????? ???? ???? ?????????,???,??,??????????-?????【??】: ?????????????????????????,???????????,????????,?????????????????????。???????-???????【??】: ?????????????????????,????????????????,????????????????,??????!???????-???????【??】: ???????????????????????,????“???????,???????”?????,????????????!?????-?????【??】: ????????????????,??????????????、???????、???????、???????、?????!??????-??????【??】: ????????????????,????,????,??????,????“????、????、????、????”????????,????????????-??????【??】: ????????????????????,????????:??、??、???,?????????????????????!??????-??????【??】: ??????????????????????????,???????????????,????????????????。??????-??????【??】: ???????????????,?????????????。?????????????,?????????,???????。??????-??????【??】: ??????????????????????????????、??????????????,??????????????。????-????【??】: ????????????:????,????,????,???????,????????,??????:????????,?????!????-????【??】: ???????????????"????,????"???,????????????????????????,??????????????。??????-??????【??】: ????????????????????,????????????,?????????????????,??????,????????!??????-??????【??】: ????????????????,???????、???????????,????????,????,?????????,??????,??????!?????-?????【??】: ???????????????????,????:????,????,????,??????,?????,???????????????!?????-?????【??】: ?????????????????,???????、????、????、??????、???????,??????,???????????。?????-?????【??】: ???????,??????,?????????????????????,???????????????????????。??????-??????【??】: ??????????????????,????????,??????????????,?????????,????,????,??????。??????-??????【??】: ??????????????、?????????,?????????,????,????????,????????????????!????-????【??】: ????????????????,???????????,??????????????,??????????,??????????????!?????-?????【??】: ?????????????????,????(??)????????,??????,????,???,????,???????!?????-?????【??】: ?????????????????????????,?????????,??????????,????????,?????!?????-?????【??】: ??????????????,???????????????,?????????????。??????-??????【??】: ??????????????????????,???????????????,????????????????????!?????-?????【??】: ?????????????????、????,??100%????,??????,????????????,???????????!?????-?????【??】: ???????????????????,??????????,????????、????,??????????,??????????。??????-??????【??】: ????????????、???、??、??????????????????????????????,????????????????!????-????【??】: ??????????????,????,????,??????,????“????、????、????、????”????????,??????.?????-?????【??】: ???????????????????,????????:??、??、???,?????????????????????!?????-?????【??】: ???????????????8?,????????,????????,??????????,?????,????? ,????????!??????-??????【??】: ?????????????????????????????、????、????、???????????,????,????!?????-?????【??】: ???????????????6?,???????????????????????????,??????????????,?????????!?????-?????【??】: ????????????、??????????????????,????????,?????,??????,????,????,????!??????-??????【??】: ????????????????????????、??????,????、?????、????, ?????????,?????????????!??????-??????【??】: ??????????????????、????、??????、????????,????????????,???????????!??????-??????【??】: ??????????????????????????????,???????????????????????,???????。????-????【??】: ???????????????????、????、????、??????、???????,??????、??????。????-????【??】: ?????????????、????、????、??????、????、???????,?????,?????????!??????-??????【??】: ????????????????,?????????????? ??。????????、????、????、?????????? ???????。??????-??????【??】: ??????????????????????????,????,????,??????????。???????????????,??,??,??????????,??????...????-????【??】: ???????????????????????????,??????????,????,????,?????????、??????,??????。?????-?????【??】: ??????????????????????:????、????、??????????????,????????。????????!?????-?????【??】: ??????????????????,?????????????,????,?????????,?????????????,?????,?????!?????-?????【??】: ????????????????,???????????????。???????????,??????:????、????、???????!??????-??????【??】: ????????????????????,?????????????????????,?????,????,?????????????-??????【??】: ??????????????????,??:??????,????,????,????,?????,??????????????.????-????【??】: ??????????????、??????、????、?????、?????!????,????????????????!????。?????-?????【??】: ???????????????????,?????????????,???????????.????????????,????????????!?????-?????【??】: ????????????????,???????????????。?????????????,???????,?????????。

    Read the article

  • Developing Schema Compare for Oracle (Part 2): Dependencies

    - by Simon Cooper
    In developing Schema Compare for Oracle, one of the issues we came across was the size of the databases. As detailed in my last blog post, we had to allow schema pre-filtering due to the number of objects in a standard Oracle database. Unfortunately, this leads to some quite tricky situations regarding object dependencies. This post explains how we deal with these dependencies. 1. Cross-schema dependencies Say, in the following database, you're populating SchemaA, and synchronizing SchemaA.Table1: SOURCE   TARGET CREATE TABLE SchemaA.Table1 ( Col1 NUMBER REFERENCES SchemaB.Table1(Col1));   CREATE TABLE SchemaA.Table1 ( Col1 VARCHAR2(100) REFERENCES SchemaB.Table1(Col1)); CREATE TABLE SchemaB.Table1 ( Col1 NUMBER PRIMARY KEY);   CREATE TABLE SchemaB.Table1 ( Col1 VARCHAR2(100) PRIMARY KEY); We need to do a rebuild of SchemaA.Table1 to change Col1 from a VARCHAR2(100) to a NUMBER. This consists of: Creating a table with the new schema Inserting data from the old table to the new table, with appropriate conversion functions (in this case, TO_NUMBER) Dropping the old table Rename new table to same name as old table Unfortunately, in this situation, the rebuild will fail at step 1, as we're trying to create a NUMBER column with a foreign key reference to a VARCHAR2(100) column. As we're only populating SchemaA, the naive implementation of the object population prefiltering (sticking a WHERE owner = 'SCHEMAA' on all the data dictionary queries) will generate an incorrect sync script. What we actually have to do is: Drop foreign key constraint on SchemaA.Table1 Rebuild SchemaB.Table1 Rebuild SchemaA.Table1, adding the foreign key constraint to the new table This means that in order to generate a correct synchronization script for SchemaA.Table1 we have to know what SchemaB.Table1 is, and that it also needs to be rebuilt to successfully rebuild SchemaA.Table1. SchemaB isn't the schema that the user wants to synchronize, but we still have to load the table and column information for SchemaB.Table1 the same way as any table in SchemaA. Fortunately, Oracle provides (mostly) complete dependency information in the dictionary views. Before we actually read the information on all the tables and columns in the database, we can get dependency information on all the objects that are either pointed at by objects in the schemas we’re populating, or point to objects in the schemas we’re populating (think about what would happen if SchemaB was being explicitly populated instead), with a suitable query on all_constraints (for foreign key relationships) and all_dependencies (for most other types of dependencies eg a function using another function). The extra objects found can then be included in the actual object population, and the sync wizard then has enough information to figure out the right thing to do when we get to actually synchronize the objects. Unfortunately, this isn’t enough. 2. Dependency chains The solution above will only get the immediate dependencies of objects in populated schemas. What if there’s a chain of dependencies? A.tbl1 -> B.tbl1 -> C.tbl1 -> D.tbl1 If we’re only populating SchemaA, the implementation above will only include B.tbl1 in the dependent objects list, whereas we might need to know about C.tbl1 and D.tbl1 as well, in order to ensure a modification on A.tbl1 can succeed. What we actually need is a graph traversal on the dependency graph that all_dependencies represents. Fortunately, we don’t have to read all the database dependency information from the server and run the graph traversal on the client computer, as Oracle provides a method of doing this in SQL – CONNECT BY. So, we can put all the dependencies we want to include together in big bag with UNION ALL, then run a SELECT ... CONNECT BY on it, starting with objects in the schema we’re populating. We should end up with all the objects that might be affected by modifications in the initial schema we’re populating. Good solution? Well, no. For one thing, it’s sloooooow. all_dependencies, on my test databases, has got over 110,000 rows in it, and the entire query, for which Oracle was creating a temporary table to hold the big bag of graph edges, was often taking upwards of two minutes. This is too long, and would only get worse for large databases. But it had some more fundamental problems than just performance. 3. Comparison dependencies Consider the following schema: SOURCE   TARGET CREATE TABLE SchemaA.Table1 ( Col1 NUMBER REFERENCES SchemaB.Table1(col1));   CREATE TABLE SchemaA.Table1 ( Col1 VARCHAR2(100)); CREATE TABLE SchemaB.Table1 ( Col1 NUMBER PRIMARY KEY);   CREATE TABLE SchemaB.Table1 ( Col1 VARCHAR2(100)); What will happen if we used the dependency algorithm above on the source & target database? Well, SchemaA.Table1 has a foreign key reference to SchemaB.Table1, so that will be included in the source database population. On the target, SchemaA.Table1 has no such reference. Therefore SchemaB.Table1 will not be included in the target database population. In the resulting comparison of the two objects models, what you will end up with is: SOURCE  TARGET SchemaA.Table1 -> SchemaA.Table1 SchemaB.Table1 -> (no object exists) When this comparison is synchronized, we will see that SchemaB.Table1 does not exist, so we will try the following sequence of actions: Create SchemaB.Table1 Rebuild SchemaA.Table1, with foreign key to SchemaB.Table1 Oops. Because the dependencies are only followed within a single database, we’ve tried to create an object that already exists. To fix this we can include any objects found as dependencies in the source or target databases in the object population of both databases. SchemaB.Table1 will then be included in the target database population, and we won’t try and create objects that already exist. All good? Well, consider the following schema (again, only explicitly populating SchemaA, and synchronizing SchemaA.Table1): SOURCE   TARGET CREATE TABLE SchemaA.Table1 ( Col1 NUMBER REFERENCES SchemaB.Table1(col1));   CREATE TABLE SchemaA.Table1 ( Col1 VARCHAR2(100)); CREATE TABLE SchemaB.Table1 ( Col1 NUMBER PRIMARY KEY);   CREATE TABLE SchemaB.Table1 ( Col1 VARCHAR2(100) PRIMARY KEY); CREATE TABLE SchemaC.Table1 ( Col1 NUMBER);   CREATE TABLE SchemaC.Table1 ( Col1 VARCHAR2(100) REFERENCES SchemaB.Table1); Although we’re now including SchemaB.Table1 on both sides of the comparison, there’s a third table (SchemaC.Table1) that we don’t know about that will cause the rebuild of SchemaB.Table1 to fail if we try and synchronize SchemaA.Table1. That’s because we’re only running the dependency query on the schemas we’re explicitly populating; to solve this issue, we would have to run the dependency query again, but this time starting the graph traversal from the objects found in the other database. Furthermore, this dependency chain could be arbitrarily extended.This leads us to the following algorithm for finding all the dependencies of a comparison: Find initial dependencies of schemas the user has selected to compare on the source and target Include these objects in both the source and target object populations Run the dependency query on the source, starting with the objects found as dependents on the target, and vice versa Repeat 2 & 3 until no more objects are found For the schema above, this will result in the following sequence of actions: Find initial dependenciesSchemaA.Table1 -> SchemaB.Table1 found on sourceNo objects found on target Include objects in both source and targetSchemaB.Table1 included in source and target Run dependency query, starting with found objectsNo objects to start with on sourceSchemaB.Table1 -> SchemaC.Table1 found on target Include objects in both source and targetSchemaC.Table1 included in source and target Run dependency query on found objectsNo objects found in sourceNo objects to start with in target Stop This will ensure that we include all the necessary objects to make any synchronization work. However, there is still the issue of query performance; the CONNECT BY on the entire database dependency graph is still too slow. After much sitting down and drawing complicated diagrams, we decided to move the graph traversal algorithm from the server onto the client (which turned out to run much faster on the client than on the server); and to ensure we don’t read the entire dependency graph onto the client we also pull the graph across in bits – we start off with dependency edges involving schemas selected for explicit population, and whenever the graph traversal comes across a dependency reference to a schema we don’t yet know about a thunk is hit that pulls in the dependency information for that schema from the database. We continue passing more dependent objects back and forth between the source and target until no more dependency references are found. This gives us the list of all the extra objects to populate in the source and target, and object population can then proceed. 4. Object blacklists and fast dependencies When we tested this solution, we were puzzled in that in some of our databases most of the system schemas (WMSYS, ORDSYS, EXFSYS, XDB, etc) were being pulled in, and this was increasing the database registration and comparison time quite significantly. After debugging, we discovered that the culprits were database tables that used one of the Oracle PL/SQL types (eg the SDO_GEOMETRY spatial type). These were creating a dependency chain from the database tables we were populating to the system schemas, and hence pulling in most of the system objects in that schema. To solve this we introduced blacklists of objects we wouldn’t follow any dependency chain through. As well as the Oracle-supplied PL/SQL types (MDSYS.SDO_GEOMETRY, ORDSYS.SI_COLOR, among others) we also decided to blacklist the entire PUBLIC and SYS schemas, as any references to those would likely lead to a blow up in the dependency graph that would massively increase the database registration time, and could result in the client running out of memory. Even with these improvements, each dependency query was taking upwards of a minute. We discovered from Oracle execution plans that there were some columns, with dependency information we required, that were querying system tables with no indexes on them! To cut a long story short, running the following query: SELECT * FROM all_tab_cols WHERE data_type_owner = ‘XDB’; results in a full table scan of the SYS.COL$ system table! This single clause was responsible for over half the execution time of the dependency query. Hence, the ‘Ignore slow dependencies’ option was born – not querying this and a couple of similar clauses to drastically speed up the dependency query execution time, at the expense of producing incorrect sync scripts in rare edge cases. Needless to say, along with the sync script action ordering, the dependency code in the database registration is one of the most complicated and most rewritten parts of the Schema Compare for Oracle engine. The beta of Schema Compare for Oracle is out now; if you find a bug in it, please do tell us so we can get it fixed!

    Read the article

  • CodePlex Daily Summary for Tuesday, June 10, 2014

    CodePlex Daily Summary for Tuesday, June 10, 2014Popular ReleasesBell Open Imaging package: 1.0: First release at Codeplex.Australia Income and Tax Calculator: Australia Income and Tax Calculator 1.4: 1. added 2014 financial year 2. refactored the codeCS-Script Source: Release v3.8.1: Improved ConfigConsole AdvancedShell extensions support cs-script.7z - CS-Script Suite (binaries, documentation, samples) cs-script.ExtensionPack.7z - CS-Script Extension Pack (additional binaries and samples) cs-scriptDocs.7z - CS-Script DocumentationPapercut: Papercut v3.0.0.0: Papercut has switched to semantic versioning! That means you will have to uninstall old "clickonce" versions to get the latest as it will see it as an older version. Latest Has Tons of New Features: Modern UI MVVM Architecture Watch Directories for New Messages Optional Backend Papercut Service Load on Windows Startup Attachments/Mime SectionsExperfwiz (Exchange Performance Data Collection tool): Experfwiz 1.3.8: List of updates in 1.3.8 Added support for Windows 2012 & 2012 R2 (for future use) Added support for Exchange 2013 Full is now enabled by default. To disable full mode, use 'nofull'. Exchange 2013 requires full. Added "\Processor Information()\" counters to Exchange 2010 full Blocked Exmon execution on Exchange 2013BugNET Issue Tracker: BugNET 1.6: Version 1.6 is a major upgrade to the latest frameworks and components by Microsoft. It includes a major UI overhaul using the bootstrap framework to have a modern, mobile friendly and easily customized layout. Upgrade to .NET 4.5 ASP.NET social auth Add script bundling and optimization Improvements for mobile devices Bootstrap (UI overhaul) Rewritten / friendly URL's Please read our release notes for BugNET 1.6: http://blog.bugnetproject.com/2014/06/08/bugnet-1-6-and-bugnet-pro-1...NDataTable: NDataTable Source Code: Source codeWindows System API in Visual Basic: DataTools Merged Beta 2.4: Added FileSystemWatcher and demonstration to this release..NET Memory Tools: DataTools Merged Beta 2.4: Added FileSystemWatcher and demonstration to this release.freeasyExplorer: 3. Alpha: This is the 3th alpha release. Please inform me if you find some issues or problems. Fixes: - add assembly informations - set list view to list mode and add custom icon - add settings window - update Mahapp.Metro Framework - add drag&drop functionality - change target .net versionkbvault-mysql: V0.16a: Additions for SEO friendly pages,printer friendly view option and tag cloud on landing pageSFDL.NET: SFDL.NET (2.2.9.3): Changelog: Retry Bugfix (Error Counter wurde nicht korrekt zurückgesetzt) Neue Einstellung: Retry Wartezeit ist nun Einstellbarbabelua: 1.5.7.0: V1.5.7.0 - 2014.6.6Stability improvement: use "lua scripts folder" as lua search path when debugging;SEToolbox: SEToolbox 01.033.007 Release 1: Fixed breaking changes in Space Engineers in latest update. Installation of this version will replace older version.Virto Commerce Enterprise Open Source eCommerce Platform (asp.net mvc): Virto Commerce 1.10: Virto Commerce Community Edition version 1.10. To install the SDK package, please refer to SDK getting started documentation To configure source code package, please refer to Source code getting started documentation This release includes bug fixes and improvements (including Commerce Manager localization and https support). More details about this release can be found on our blog at http://blog.virtocommerce.com.NPOI: NPOI 2.1: Assembly Version: 2.1.0 New Features a. XSSFSheet.CopySheet b. Excel2Html for XSSF c. insert picture in word 2007 d. Implement IfError function in formula engine Bug Fixes a. fix conditional formatting issue b. fix ctFont order issue c. fix vertical alignment issue in XSSF d. add IndexedColors to NPOI.SS.UserModel e. fix decimal point issue in non-English culture f. fix SetMargin issue in XSSF g.fix multiple images insert issue in XSSF h.fix rich text style missing issue in XSSF i. fix cell...51Degrees - Device Detection and Redirection: 3.1.2.3: Version 3.1 HighlightsDevice detection algorithm is over 100 times faster. Regular expressions and levenshtein distance calculations are no longer used. The device detection algorithm performance is no longer limited by the number of device combinations contained in the dataset. Two modes of operation are available: Memory – the detection data set is loaded into memory and there is no continuous connection to the source data file. Slower initialisation time but faster detection performanc...CS-Script for Notepad++ (C# intellisense and code execution): Release v1.0.27.0: CodeMap now indicates the type name for all members Implemented running scripts 'as administrator'. Just add '//css_npp asadmin' to the script and run it as usual. 'Prepare script for distribution' now aggregates script dependency assemblies. Various improvements in CodeSnipptet, Autcompletion and MethodInfo interactions with each other. Added printing line number for the entries in CodeMap (subject of configuration value) Improved debugging step indication for classless scripts ...ClosedXML - The easy way to OpenXML: ClosedXML 0.72.3: 70426e13c415 ClosedXML for .Net 4.0 now uses Open XML SDK 2.5 b9ef53a6654f Merge branch 'master' of https://git01.codeplex.com/forks/vbjay/closedxml 727714e86416 Fix range.Merge(Boolean) for .Net 3.5 eb1ed478e50e Make public range.Merge(Boolean checkIntersects) 6284cf3c3991 More performance improvements when saving.DNN Blog: 06.00.07: Highlights: Enhancement: Option to show management panel on child modules Fix: Changed SPROC and code to ensure the right people are notified of pending comments. (CP-24018) Fix: Fix to have notification actions authentication assume the right module id so these will work from the messaging center (CP-24019) Fix: Fix to issue in categories in a post that will not save when no categories and no tags selectedNew ProjectsATC FSX Console: Flight Simulator CodeCRM 2011 Duplicate Detection Sample: CRM 2011 Duplicate Detection Plug-in SampleCustomisation tool for Visual Studio projects: This tool is used to speedup the setting up of a Visual Studio projects and suppress any repetitive manual tasks.D3 Focus: A basic tool for people with trouble deciding what to do with their time in Diablo 3.EPS - PowerShell templating: EPS (Embedded PowerShell), inspired by erb, is a templating system that embeds PowerShell code into a text document such as HTML files. Export Bugs: Export Bugs is an application using the TFS API. Killer Bytes Pack: project of class visual studioMagickViewer: An application that uses the Magick.NET library to display images.Mario Card: https://drive.google.com/?authuser=0#folders/0B0VMM5klwOkwLXptMVV6b3NhRVEOZone: OZonePlexApp PowerShell Module: PoSH4PlexApp is an in-development PowerShell module for querying and managing PlexApp libraries via Plex Media Server's HTTP listener. Contributions welcomeProduct Usage Tracker: This project is about creating a tool/mechanism to capture and record the usage volume and usage patterns of any application.Project C²: A simple lightweight C-style programming language for near-hardware system development using GNU GAS as a back-end.Random Execute: Random Execute is a command wrapper that randomizes the start time of a processes execution.RuLaw.NET: .NET library for official Russian State Duma API web service for querying and searching information of laws, deputies, authorities, sessions, votings, etcTest_DB_Name_Check: Latestweb_gioman_proyecto: proyecto de lucas gioiaWPF Globalization and Multi-language Application: Multilingual User Interfaces providing support for switching UIs from one language to another. ??????-??????【??】: ????????,??????:?????,?????,??????,??????????,????????。????????!??????-??????【??】: ?????????????????????????????,??????????,????,????,?????????、??????,??????。?????-?????【??】: ???????????????????,??????????,????????、????,??????????,??????????。?????-?????【??】: ?????????????????、????,??100%????,??????,????????????,???????????!?????-?????【??】: ??????????????????????:????、????、??????????????,????????。????????!??????-??????【??】: ??????????????????????????,????,????,??????????。???????????????,??,??,??????????,????????????-??????【??】: ???????????????????,?????????????,????,?????????,?????????????,?????,?????!??????-??????【??】: ??????????????????,???????????,??????????????,??????????,??????????????!?????-?????【??】: ????【??:13406937288 ??? QQ:798761615】???????????????,???,??????????、???????????????????。??????,????、????,??????! ?????-?????【??】: ???????????????,?????????????? ??。????????、????、????、?????????? ???????。?????-?????【??】: ????????????????,???????????????。???????????,??????:????、????、????????????-?????【??】: ???????【??:13406937288 ??? QQ:798761615】?????????????????,????,????“???、???、???”?????,?????,?????????????????。??????!?????-?????【??】: ?????????【??:13406937288 ??? QQ:798761615】,???????????,??????????,????:??,????,???????? ??????????,????????。??????!?????-?????【??】: ?????【??:13406937288 ??? QQ:798761615】????:?????,??????!???????????????,???????、?????、??????“??”????,????,????!?????-?????【??】: ???????【??:13406937288 ??? QQ:798761615】???????,??????,??????,??????、??????,??????、??,????,????????????-??????【??】: ?????????【??:13406937288 ??? QQ:798761615】????????????????????,???????????,??????,??????????????...????????。??????!?????-?????【??】: ???????【??:13406937288 ??? QQ:798761615】?????????、?????????,??????、??????????????????,???????.??????????,????????。??????-??????【??】: ?????????????????,??????????、??????,??????????、????、????、???????。??????-??????【??】: ??????????????????????,???????????????,???????,?????,?????,????? !!!?????-?????【??】: ???????【??:13406937288 ??? QQ:798761615】????????,????,?????、???、?????,???????,?????,???????????100%。??????!????-????【??】: ???????????、??????????????????,????????,?????,??????,????,????,????!?????-?????【??】: ?????????????????????,???????????????,????????????????????!?????-?????【??】: ?????????【??:13406937288 ??? QQ:798761615】???2005?,????????????????????,??????????,??????。?????,???????????????????,??????!?????-?????【??】: ???????【??:13406937288 ??? QQ:798761615】???????:??????!?????!???:????、????、????、????。??,??????????!??????.?????-?????【??】: ???????【??:13406937288 ??? QQ:798761615】??????????,????????????,????????,???,???????????,????,????。?????,??????. ?????-?????【??】: ?????????????????:??????!?????!???:????、????、????、????。??,??????????!??????.?????-?????【??】: ???????【??:13406937288 ??? QQ:798761615】 ?????????????????,????,????“???、???、???”?????,?????,?????????????????。??????!?????-?????【??】: ???????【??:13406937288 ??? QQ:798761615】?????????????,??????,???????????,????????????????,????????.??????.?????-?????【??】: ???????【??:13406937288 ??? QQ:798761615】???1992?,????????????????。??????????????????????。????????????,????,????????!?????-?????【??】: ?????【??:13406937288 ??? QQ:798761615】??????:?????,??????!???????????????,???????、?????、??????“??”????,????,????! ?????-?????【??】: ???????【??:13406937288 ??? QQ:798761615】????????,????,?????、???、?????,???????,?????,???????????100%。??????!??????-??????【??】: ????????【??:13406937288 ??? QQ:798761615】?????????、?????????,??????、??????????????????,???????.??????????,????????。?????-?????【??】: ???????【??:13406937288 ??? QQ:798761615】???1992?,????????????????。??????????????????????。????????????,????,????????! ?????-?????【??】: ?????????【??:13406937288 ??? QQ:798761615】???2005?,????????????????????,??????????,??????。?????,???????????????????,??????!?????-?????【??】: ???????【??:13406937288 ??? QQ:798761615】??????????????????,???????????,??????,??????????????...????????。??????!?????-?????【??】: ?????????????【??:13406937288 ??? QQ:798761615】?????????????,??????,???????????,????????????????,????????.??????.??????-??????【??】: ???????????,?????,???????????,???????,????,????,????,?????。??????-??????【??】: ????????????????8?,????????,????????,??????????,?????,????? ,????????!??????-??????【??】: ????????????????6?,???????????????????????????,??????????????,?????????!?????-?????【??】: ?????????????【??:13406937288 ??? QQ:798761615】???????,??????,??????,??????、??????,??????、??,????,??????!?????-?????【??】: ???????????、???、??、??????????????????????????????,????????????????!?????-?????【??】: ????????????????????????????、????、????、???????????,????,????!?????-?????【??】: ???????【??:13406937288 ??? QQ:798761615】?????????????????,????,????“???、???、???”?????,?????,?????????????????。??????!?????-?????【??】: ???????【??:13406937288 ??? QQ:798761615】??????????,????????????,????????,???,???????????,????,????。?????,??????.

    Read the article

  • Framework 4 Features: Support for Timed Jobs

    - by Anthony Shorten
    One of the new features of the Oracle Utilities Application Framework V4 is the ability for the batch framework to support Timed Batch. Traditionally batch is associated with set processing in the background in a fixed time frame. For example, billing customers. Over the last few versions their has been functionality required by the products required a more monitoring style batch process. The monitor is a batch process that looks for specific business events based upon record status or other pieces of data. For example, the framework contains a fact monitor (F1-FCTRN) that can be configured to look for specific status's or other conditions. The batch process then uses the instructions on the object to determine what to do. To support monitor style processing, you need to run the process regularly a number of times a day (for example, every ten minutes). Traditional batch could support this but it was not as optimal as expected (if you are a site using the old Workflow subsystem, you understand what I mean). The Batch framework was extended to add additional facilities to support times (and continuous batch which is another new feature for another blog entry). The new facilities include: The batch control now defines the job as Timed or Not Timed. Non-Timed batch are traditional batch jobs. The timer interval (the interval between executions) can be specified The timer can be made active or inactive. Only active timers are executed. Setting the Timer Active to inactive will stop the job at the next time interval. Setting the Timer Active to Active will start the execution of the timed job. You can specify the credentials, language to view the messages and an email address to send the a summary of the execution to. The email address is optional and requires an email server to be specified in the relevant feature configuration. You can specify the thread limits and commit intervals to be sued for the multiple executions. Once a timer job is defined it will be executed automatically by the Business Application Server process if the DEFAULT threadpool is active. This threadpool can be started using the online batch daemon (for non-production) or externally using the threadpoolworker utility. At that time any batch process with the Timer Active set to Active and Batch Control Type of Timed will begin executing. As Timed jobs are executed automatically then they do not appear in any external schedule or are managed by an external scheduler (except via the DEFAULT threadpool itself of course). Now, if the job has no work to do as the timer interval is being reached then that instance of the job is stopped and the next instance started at the timer interval. If there is still work to complete when the interval interval is reached, the instance will continue processing till the work is complete, then the instance will be stopped and the next instance scheduled for the next timer interval. One of the key ways of optimizing this processing is to set the timer interval correctly for the expected workload. This is an interesting new feature of the batch framework and we anticipate it will come in handy for specific business situations with the monitor processes.

    Read the article

  • WCF REST Service Activation Errors when AspNetCompatibility is enabled

    - by Rick Strahl
    I’m struggling with an interesting problem with WCF REST since last night and I haven’t been able to track this down. I have a WCF REST Service set up and when accessing the .SVC file it crashes with a version mismatch for System.ServiceModel: Server Error in '/AspNetClient' Application. Could not load type 'System.ServiceModel.Activation.HttpHandler' from assembly 'System.ServiceModel, Version=3.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'.Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.TypeLoadException: Could not load type 'System.ServiceModel.Activation.HttpHandler' from assembly 'System.ServiceModel, Version=3.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'.Source Error: An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below. Stack Trace: [TypeLoadException: Could not load type 'System.ServiceModel.Activation.HttpHandler' from assembly 'System.ServiceModel, Version=3.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'.] System.RuntimeTypeHandle.GetTypeByName(String name, Boolean throwOnError, Boolean ignoreCase, Boolean reflectionOnly, StackCrawlMarkHandle stackMark, Boolean loadTypeFromPartialName, ObjectHandleOnStack type) +0 System.RuntimeTypeHandle.GetTypeByName(String name, Boolean throwOnError, Boolean ignoreCase, Boolean reflectionOnly, StackCrawlMark& stackMark, Boolean loadTypeFromPartialName) +95 System.RuntimeType.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase, Boolean reflectionOnly, StackCrawlMark& stackMark) +54 System.Type.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase) +65 System.Web.Compilation.BuildManager.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase) +69 System.Web.Configuration.HandlerFactoryCache.GetTypeWithAssert(String type) +38 System.Web.Configuration.HandlerFactoryCache.GetHandlerType(String type) +13 System.Web.Configuration.HandlerFactoryCache..ctor(String type) +19 System.Web.HttpApplication.GetFactory(String type) +81 System.Web.MaterializeHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +223 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +184 Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.1 What’s really odd about this is that it crashes only if it runs inside of IIS (it works fine in Cassini) and only if ASP.NET Compatibility is enabled in web.config:<serviceHostingEnvironment aspNetCompatibilityEnabled="true" multipleSiteBindingsEnabled="true" /> Arrrgh!!!!! After some experimenting and some help from Glenn Block and his team mates I was able to track down the problem in ApplicationHost.config. Specifically the problem was that there were multiple *.svc mappings in the ApplicationHost.Config file and the older 2.0 runtime specific versions weren’t marked for the proper runtime. Because these handlers show up at the top of the list they execute first resulting in assembly load errors for the wrong version assembly. To fix this problem I ended up making a couple changes in applicationhost.config. On the machine level root’s Handler mappings I had an entry that looked like this:<add name="svc-Integrated" path="*.svc" verb="*" type="System.ServiceModel.Activation.HttpHandler, System.ServiceModel, Version=3.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" preCondition="integratedMode" /> and it needs to be changed to this:<add name="svc-Integrated" path="*.svc" verb="*" type="System.ServiceModel.Activation.HttpHandler, System.ServiceModel, Version=3.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" preCondition="integratedMode,runtimeVersionv2.0" />Notice the explicit runtime version assignment in the preCondition attribute which is key to keep ASP.NET 4.0 from executing that handler. The key here is that the runtime version needs to be set explicitly so that the various *.svc handlers don’t fire only in the order defined which in case of a .NET 4.0 app with the original setting would result in an incompatible version of System.ComponentModel to load.What was really hard to track this down is that even when looking in the debugger when launching the Web app, the AppDomain assembly loads showed System.ServiceModel V4.0 starting up just fine. Apparently the ASP.NET runtime load occurs at a different point and that’s when things break.So how did this break? According to the Microsoft folks it’s some older tools that got installed that change the default service handlers. There’s a blog entry that points at this problem with more detail:http://blogs.iis.net/webtopics/archive/2010/04/28/system-typeloadexception-for-system-servicemodel-activation-httpmodule-in-asp-net-4.aspxNote that I tried running aspnet_regiis and that did not fix the problem for me. I had to manually change the entries in applicationhost.config.   © Rick Strahl, West Wind Technologies, 2005-2011Posted in AJAX   ASP.NET  WCF  

    Read the article

  • MEB Support to NetBackup MMS

    - by Hema Sridharan
    In MySQL Enterprise Backup 3.6, new option was introduced to support backup to tapes via SBT interface. SBT stands for System Backup to Tape, an Oracle API that helps to perform backup and restore jobs via media management software such as Oracle's Secure Backup (OSB). There are other storage managers like IBM's Tivoli Storage Manager (TSM) and Symantec's Netbackup (NB) which are also supported by MEB but we don't guarantee that it will function as expected for every release. MEB supports SBT API version 2.0 In this blog, I am primarily going to focus the interface of MEB and Symantec's NB. If we are using tapes for backup, ensure that tape library and tape drives are compatible. Test Setup 1. Install NB 7.5 master and media servers in Linux OS. ( NB 7.1 can also be used but for testing purpose I used NB 7.5)2. Install MEB 3.8 also in Linux OS.3. Install NB admin console in your windows desktop and configure the NB master server from there. Note: Ensure that you have root user permission to install NetBackup. Configuration Steps for MEB and NB Once MEB and NB are installed, Ensure that NB is linked to MEB by specifying the library /usr/openv/netbackup/bin/libobk.so64 in the mysqlbackup command line using --sbt-lib-path. Configure the NB master server from windows console. That is configure the storage units by specifying the Storage unit name, Disk type, Media Server name etc.  Create NetBackup policies that are user selectable. But please make sure that policy type is "Oracle".  Define the clients where MEB will be executed. Some times this will be different host where MEB is run or some times in same Media server where NB and tapes are attached. Now once the installation and configuration steps are performed for MEB and NB, the next part is the actual execution.MEB should be run as single file backup using --backup-image option with prefix sbt:(it is a tag which tells MEB that it should stream the backup image through the SBT interface) which is sent to NB client via SBT interface . The resulting backup image is stored where NB stores the images that it backs up. The following diagram shows how MEB interacts with MMS through SBT interface. Backup The following parameters should also be ready for the execution,    --sbt-lib-path : Path to SBT library specific to NetBackup MMS. SBT lib for NetBackup  is in /usr/openv/netbackup/bin/libobk.so64    --sbt-environment: Environment variables must be defined specific to NetBackup. In our example below, we use     NB_ORA_SERV=myserver.com,    NB_ORA_CLIENT=myserver.com,    NB_ORA_POLICY=NBU-MEB    ORACLE_HOME = /export/home2/tmp/hema/mysql-server/ ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ./mysqlbackup --port=13000 --protocol=tcp --user=root --backup-image=sbt:bkpsbtNB --sbt-lib-path=/usr/openv/netbackup/bin/libobk.so64 --sbt-environment="NB_ORA_SERV=myserver.com, NB_ORA_CLIENT=myserver.com, NB_ORA_POLICY=NBU-MEB, ORACLE_HOME=/export/home2/tmp/hema/mysql-server/” --backup-dir=/export/home2/tmp/hema/MEB_bkdir/ backup-to-image ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Once backup is completed successfully, this should appear in Activity Monitor in NetBackup Console.For restore,  image contents has to be extracted using image-to-backup-dir command and then apply-log and copy-back steps are applied. ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ./mysqlbackup --sbt-lib-path=/usr/openv/netbackup/bin/libobk.so64  --backup-dir=/export/home2/tmp/hema/NBMEB/ --backup-image=sbt:bkpsbtNB image-to-backup-dir-----------------------------------------------------------------------------------------------------------------------------------Now apply logs as usual, shutdown the server and perform restore, restart the server and check the data contents. ./mysqlbackup   ---backup-dir=/export/home2/tmp/hema/NBMEB/  apply-log ./mysqlbackup --datadir=/export/home2/tmp/hema/mysql-server/mysql-5.5-meb-repo/mysql-test/var/mysqld.1/data/  --backup-dir=/export/home2/tmp/hema/MEB_bkpdir/ innodb_log_files_in_group=2 --innodb_log_file_size=5M --user=root --port=13000 --protocol=tcp copy-back The NB console should show 'Restore" job as done. If you don't see that there is something wrong with MEB or NetBackup.You can also refer to more detailed steps of MEB and NB integration in whitepaper here

    Read the article

  • Lies, damned lies, and statistics Part 2

    - by Maria Colgan
    There was huge interest in our OOW session last year on Managing Optimizer Statistics. It seems statistics and the maintenance of them continues to baffle people. In order to help dispel the mysteries surround statistics management we have created a two part white paper series on Optimizer statistics.  Part one of this series was released in November last years and describes in detail, with worked examples, the different concepts of Optimizer statistics. Today we have published part two of the series, which focuses on the best practices for gathering statistics, and examines specific use cases including, the fears that surround histograms and statistics management of volatile tables like Global Temporary Tables. Here is a quick look at the Introduction and the start of the paper. You can find the full paper here. Happy Reading! Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman","serif";} Introduction The Oracle Optimizer examines all of the possible plans for a SQL statement and picks the one with the lowest cost, where cost represents the estimated resource usage for a given plan. In order for the Optimizer to accurately determine the cost for an execution plan it must have information about all of the objects (table and indexes) accessed in the SQL statement as well as information about the system on which the SQL statement will be run. This necessary information is commonly referred to as Optimizer statistics. Understanding and managing Optimizer statistics is key to optimal SQL execution. Knowing when and how to gather statistics in a timely manner is critical to maintaining acceptable performance. This whitepaper is the second of a two part series on Optimizer statistics. The first part of this series, Understanding Optimizer Statistics, focuses on the concepts of statistics and will be referenced several times in this paper as a source of additional information. This paper will discuss in detail, when and how to gather statistics for the most common scenarios seen in an Oracle Database. The topics are · How to gather statistics · When to gather statistics · Improving the efficiency of gathering statistics · When not to gather statistics · Gathering other types of statistics How to gather statistics The preferred method for gathering statistics in Oracle is to use the supplied automatic statistics-gathering job. Automatic statistics gathering job The job collects statistics for all database objects, which are missing statistics or have stale statistics by running an Oracle AutoTask task during a predefined maintenance window. Oracle internally prioritizes the database objects that require statistics, so that those objects, which most need updated statistics, are processed first. The automatic statistics-gathering job uses the DBMS_STATS.GATHER_DATABASE_STATS_JOB_PROC procedure, which uses the same default parameter values as the other DBMS_STATS.GATHER_*_STATS procedures. The defaults are sufficient in most cases. However, it is occasionally necessary to change the default value of one of the statistics gathering parameters, which can be accomplished by using the DBMS_STATS.SET_*_PREF procedures. Parameter values should be changed at the smallest scope possible, ideally on a per-object bases. You can find the full paper here. Happy Reading! +Maria Colgan

    Read the article

  • Acr.ExtDirect &ndash; Part 1 &ndash; Method Resolvers

    - by Allan Ritchie
    One of the most important things of any open source libraries in my opinion is to be as open as possible while avoiding having your library become invasive to your code/business model design.  I personally could never stand marking my business and/or data access code with attributes everywhere.  XML also isn’t really a fav with too many people these days since it comes with a startup performance hit and requires runtime compiling.  I find that there is a whole ton of communication libraries out there currently requiring this (ie. WCF, RIA, etc).  Even though Acr.ExtDirect comes with its own set of attributes, you can piggy-back the [ServiceContract] & [OperationContract] attributes from WCF if you choose.  It goes beyond that though, there are 2 others “out-of-the-box” implementations – Convention based & XML Configuration.    Convention – I don’t actually recommend using this one since it opens up all of your public instance methods to remote execution calls. XML Configuration – This isn’t so bad but requires you enter all of your methods and there operation types into the Castle XML configuration & as I said earlier, XML isn’t the fav these days.   So what are your options if you don’t like attributes, convention, or XML Configuration?  Well, Acr.ExtDirect has its own extension base to give the API a list of methods and components to make available for remote execution.  1: public interface IDirectMethodResolver { 2:   3: bool IsServiceType(ComponentModel model, Type type); 4: string GetNamespace(ComponentModel model); 5: string[] GetDirectMethodNames(ComponentModel model); 6: DirectMethodType GetMethodType(ComponentModel model, MethodInfo method); 7: }   Now to implement our own method resolver:   1: public class TestResolver : IDirectMethodResolver { 2:   3: #region IDirectMethodResolver Members 4:   5: /// <summary> 6: /// Determine if you are calling a service 7: /// </summary> 8: /// <param name="model"></param> 9: /// <param name="type"></param> 10: /// <returns></returns> 11: public bool IsServiceType(ComponentModel model, Type type) { 12: return (type.Namespace == "MyBLL.Data"); 13: } 14:   15: /// <summary> 16: /// Return the calling name for the client side 17: /// </summary> 18: /// <param name="model"></param> 19: /// <returns></returns> 20: public string GetNamespace(ComponentModel model) { 21: return model.Name; 22: } 23:   24: public string[] GetDirectMethodNames(ComponentModel model) { 25: switch (model.Name) { 26: case "Products" : 27: return new [] { 28: "GetProducts", 29: "LoadProduct", 30: "Save", 31: "Update" 32: }; 33:   34: case "Categories" : 35: return new [] { 36: "GetProducts" 37: }; 38:   39: default : 40: throw new ArgumentException("Invalid type"); 41: } 42: } 43:   44: public DirectMethodType GetMethodType(ComponentModel model, MethodInfo method) { 45: if (method.Name.StartsWith("Save") || method.Name.StartsWith("Update")) 46: return DirectMethodType.FormSubmit; 47: 48: else if (method.Name.StartsWith("Load")) 49: return DirectMethodType.FormLoad; 50:   51: else 52: return DirectMethodType.Direct; 53: } 54:   55: #endregion 56: }   And there you have it, your own custom method resolver.  Pretty easy and pretty open ended!

    Read the article

  • First Day of Data Integration Track at Oracle OpenWorld 2012

    - by Irem Radzik
    OpenWorld started full speed for us today with a great set of sessions in the Data Integration track. After the exciting keynote session on Oracle Database 12c in the morning; Brad Adelberg, VP of Development for Data Integration products, presented Oracle’s data integration product strategy. His session highlighted the new requirements for data integration to achieve pervasive and continuous access to trusted data. The new requirements and product focus areas presented in this session are: Provide access to any data at any source On premise or on cloud Enable zero downtime operations and maximum performance Leverage real-time data for accurate business insights And ensure high quality data is used across the enterprise During the session Brad walked over how Oracle’s data integration products, Oracle Data Integrator, Oracle GoldenGate, Oracle Enterprise Data Quality, and Oracle Data Service Integrator, deliver on these requirements and how recent product releases build on this strategy. Soon after Brad’s session we heard from a panel of Oracle GoldenGate customers, St. Jude Medical, Equifax, and Bank of America, how they achieved zero downtime operations using Oracle GoldenGate. The panel presented different use cases of GoldenGate, from Active-Active replication to offloading reporting. Especially St. Jude Medical’s implementation, which involves the alert management system for patients that use their pacemakers, reminded me in some cases downtime of mission-critical systems can be a matter of life or death. It is very comforting to hear that GoldenGate delivers highly-reliable continuous availability for life-saving medical systems. In the afternoon, Nick Wagner from the Product Management team and I followed the customer panel with the review of Oracle GoldenGate 11gR2’s New Features.  Many questions we received from audience were about GoldenGate’s new Integrated Capture for Oracle Database and the enhanced Conflict Management features, as well as how GoldenGate compares to Oracle Streams. In addition to giving details on GoldenGate’s unique capability to capture changed data with a direct integration to the Oracle DBMS engine, we reminded the audience that enhancements to Oracle GoldenGate will continue, while Streams will be primarily maintained. Last but not least, Tim Garrod and Ryan Fonnett from Raymond James presented a unified real-time data integration solution using Oracle Data Integrator and GoldenGate for their operational data store (ODS). The ODS supports application services across the enterprise and providing timely data is a critical requirement. In this solution, Oracle GoldenGate does the log-based change data capture for Oracle Data Integrator’s near real-time data integration between heterogeneous systems. As Raymond James’ ODS supports mission-critical services for their advisors, the project team had to set up this integration environment to be highly available. During the session, Ryan and Tim explained how they use ODI to enable automated process execution and “always-on” integration processes. Their presentation included 2 demonstrations that focused on CDC patterns deployed with ODI and the automated multi-instance execution and monitoring. We are very grateful to Tim and Ryan for their very-well prepared presentation at OpenWorld this year. Day 2 (Tuesday) will be also a busy day in our track. In addition to the Fusion Middleware Innovation Awards ceremony at 11:45am at Moscone West 3001, we have the following DI sessions Real-World Operational Reporting Customer Panel 11:45am Moscone West- 3005 Oracle Data Integrator Product Update and Future Strategy 1:15pm Moscone West- 3005 High-volume OLTP with Oracle GoldenGate: Best Practices from Comcast 1:15pm Moscone West- 3005 Everything You need to Know about Monitoring Oracle GoldenGate 5pm Moscone West-3005 If you are at OpenWorld please join us in these sessions. For a full review of data integration track at OpenWorld please see our Focus-On document.

    Read the article

  • Looking under the hood of SSRS

    - by Jim Giercyk
    SSRS is a powerful tool, but there is very little available to measure it’s performance or view the SSRS execution log or catalog in detail.  Here are a few simple queries that will give you insight to the system that you never had before.   ACTIVE REPORTS:  Have you ever seen your SQL Server performance take a nose dive due to a long-running report?  If the SPID is executing under a generic Report ID, or it is a scheduled job, you may have no way to tell which report is killing your server.  Running this query will show you which reports are executing at a given time, and WHO is executing them.   USE ReportServerNative SELECT runningjobs.computername,             runningjobs.requestname,              runningjobs.startdate,             users.username,             Datediff(s,runningjobs.startdate, Getdate()) / 60 AS    'Active Minutes' FROM runningjobs INNER JOIN users ON runningjobs.userid = users.userid ORDER BY runningjobs.startdate               SSRS CATALOG:  We have all asked “What was the last thing that changed”, or better yet, “Who in the world did that!”.  Here is a query that will show all of the reports in your SSRS catalog, when they were created and changed, and by who.           USE ReportServerNative SELECT DISTINCT catalog.PATH,                            catalog.name,                            users.username AS [Created By],                             catalog.creationdate,                            users_1.username AS [Modified By],                            catalog.modifieddate FROM catalog         INNER JOIN users ON catalog.createdbyid = users.userid  INNER JOIN users AS users_1 ON catalog.modifiedbyid = users_1.userid INNER JOIN executionlogstorage ON catalog.itemid = executionlogstorage.reportid WHERE ( catalog.name <> '' )               SSRS EXECUTION LOG:  Sometimes we need to know what was happening on the SSRS report server at a given time in the past.  This query will help you do just that.  You will need to set the timestart and timeend in the WHERE clause to suit your needs.         USE ReportServerNative SELECT catalog.name AS report,        executionlogstorage.username AS [User],        executionlogstorage.timestart,        executionlogstorage.timeend,         Datediff(mi,e.timestart,e.timeend) AS ‘Time In Minutes',        catalog.modifieddate AS [Report Last Modified],        users.username FROM   catalog  (nolock)        INNER JOIN executionlogstorage e (nolock)          ON catalog.itemid = executionlogstorage.reportid        INNER JOIN users (nolock)          ON catalog.modifiedbyid = users.userid WHERE  executionlogstorage.timestart >= Dateadd(s, -1, '03/31/2012')        AND executionlogstorage.timeend <= Dateadd(DAY, 1, '04/02/2012')      LONG RUNNING REPORTS:  This query will show the longest running reports over a given time period.  Note that the “>5” in the WHERE clause sets the report threshold at 5 minutes, so anything that ran less than 5 minutes will not appear in the result set.  Adjust the threshold and start/end times to your liking.  With this information in hand, you can better optimize your system by tweaking the longest running reports first.         USE ReportServerNative SELECT executionlogstorage.instancename,        catalog.PATH,        catalog.name,        executionlogstorage.username,        executionlogstorage.timestart,        executionlogstorage.timeend,        Datediff(mi, e.timestart, e.timeend) AS 'Minutes',        executionlogstorage.timedataretrieval,        executionlogstorage.timeprocessing,        executionlogstorage.timerendering,        executionlogstorage.[RowCount],        users_1.username        AS createdby,        CONVERT(VARCHAR(10), catalog.creationdate, 101)        AS 'Creation Date',        users.username        AS modifiedby,        CONVERT(VARCHAR(10), catalog.modifieddate, 101)        AS 'Modified Date' FROM   executionlogstorage e         INNER JOIN catalog          ON executionlogstorage.reportid = catalog.itemid        INNER JOIN users          ON catalog.modifiedbyid = users.userid        INNER JOIN users AS users_1          ON catalog.createdbyid = users_1.userid WHERE  ( e.timestart > '03/31/2012' )        AND ( e.timestart <= '04/02/2012' )        AND  Datediff(mi, e.timestart, e.timeend) > 5        AND catalog.name <> '' ORDER  BY 'Minutes' DESC        I have used these queries to build SSRS reports that I can refer to quickly, and export to Excel if I need to report or quantify my findings.  I encourage you to look at the data in the ReportServerNative database on your report server to understand the queries and create some of your own.  For instance, you may want a query to determine which reports are using which shared data sources.  Work smarter, not harder!

    Read the article

  • Seizing the Moment with Mobility

    - by Kathryn Perry
    A guest post by Hernan Capdevila, Vice President, Oracle Fusion Apps Mobile devices are forcing a paradigm shift in the workplace – they’re changing the way businesses can do business and the type of cultures they can nurture. As our customers talk about their mobile needs, we hear them saying they want instant-on access to enterprise data so workers can be more effective at their jobs anywhere, anytime. They also are interested in being more cost effective from an IT point of view. The mobile revolution – with the idea of BYOD (bring your own device) – has added an interesting dynamic because previously IT was driving the employee device strategy and ecosystem. That's been turned on its head with the consumerization of IT. Now employees are figuring out how to use their personal devices for work purposes and IT has to figure out how to adapt. Blurring the Lines between Work and Personal Life My vision of where businesses will be five years from now is that our work lives and personal lives will be more interwoven together. In turn, enterprises will have to determine how to make employees’ work lives fit more into the fabric of their personal lives. And personal devices like smartphones are going to drive significant business value because they let us accomplish things very incrementally. I can be sitting on a train or in a taxi and be productive. At the end of any meeting, I can capture ideas and tasks or follow up with people in real time. Mobile devices enable this notion of seizing the moment – capitalizing on opportunities that might otherwise have slipped away because we're not connected. For the industry shapers out there, this is game changing. The lean and agile workforce is definitely the future. This notion of the board sitting down with the executive team to lay out strategic objectives for a three- to five-year plan, bringing in HR to determine how they're going to staff the strategic activities, kicking off the execution, and then revisiting the plan in three to five years to create another three- to five-year plan is yesterday's model. Businesses that continue to approach innovating in that way are in the dinosaur age. Today it's about incremental planning and incremental execution, which requires a lot of cohesion and synthesis within the workforce. There needs to be this interweaving notion within the workforce about how ideas cascade down, how people engage, how they stay connected, and how insights are shared. How to Survive and Thrive in Today’s Marketplace The notion of Facebook isn’t new. We lived it pre-Internet days with America Online and Prodigy – Facebook is just the renaissance of these services in a more viral and pervasive way. And given the trajectory of the consumerization of IT with people bringing their personal tooling to work, the enterprise has no option but to adapt. The sooner that businesses realize this from a top-down point of view the sooner that they will be able to really drive significant innovation and adapt to the marketplace. There are a small number of companies right now (I think it's closer to 20% rather than 80%, but the number is expanding) that are able to really innovate in this incremental marketplace. So from a competitive point of view, there's no choice but to be social and stay connected. By far the majority of users on Facebook and LinkedIn are mobile users – people on iPhones, smartphones, Android phones, and tablets. It's not the couch people, right? It's the on-the-go people – those people at the coffee shops. Usually when you're sitting at your desk on a big desktop computer, typically you have better things to do than to be on Facebook. This is a topic I'm extremely passionate about because I think mobile devices are game changing. Mobility delivers significant value to businesses – it also brings dramatic simplification from a functional point of view and transforms our work life experience. Hernan CapdevilaVice President, Oracle Applications Development

    Read the article

  • PASS Summit 2011 &ndash; Part II

    - by Tara Kizer
    I arrived in Seattle last Monday afternoon to attend PASS Summit 2011.  I had really wanted to attend Gail Shaw’s (blog|twitter) and Grant Fritchey’s (blog|twitter) pre-conference seminar “All About Execution Plans” on Monday, but that would have meant flying out on Sunday which I couldn’t do.  On Tuesday, I attended Allan Hirt’s (blog|twitter) pre-conference seminar entitled “A Deep Dive into AlwaysOn: Failover Clustering and Availability Groups”.  Allan is a great speaker, and his seminar was packed with demos and information about AlwaysOn in SQL Server 2012.  Unfortunately, I have lost my notes from this seminar and the presentation materials are only available on the pre-con DVD.  Hmpf! On Wednesday, I attended Gail Shaw’s “Bad Plan! Sit!”, Andrew Kelly’s (blog|twitter) “SQL 2008 Query Statistics”, Dan Jones’ (blog|twitter) “Improving your PowerShell Productivity”, and Brent Ozar’s (blog|twitter) “BLITZ! The SQL – More One Hour SQL Server Takeovers”.  In Gail’s session, she went over how to fix bad plans and bad query patterns.  Update your stale statistics! How to fix bad plans Use local variables – optimizer can’t sniff it, so it’ll optimize for “average” value Use RECOMPILE (at the query or stored procedure level) – CPU hit OPTIMIZE FOR hint – most common value you’ll pass How to fix bad query patterns Don’t use them – ha! Catch-all queries Use dynamic SQL OPTION (RECOMPILE) Multiple execution paths Split into multiple stored procedures OPTION (RECOMPILE) Modifying parameter values Use local variables Split into outer and inner procedure OPTION (RECOMPILE) She also went into “last resort” and “very last resort” options, but those are risky unless you know what you are doing.  For the average Joe, she wouldn’t recommend these.  Examples are query hints and plan guides. While I enjoyed Andrew’s session, I didn’t take any notes as it was familiar material.  Andrew is a great speaker though, and I’d highly recommend attending his sessions in the future. Next up was Dan’s PowerShell session.  I need to look into profiles, manifests, function modules, and function import scripts more as I just didn’t quite grasp these concepts.  I am attending a PowerShell training class at the end of November, so maybe that’ll help clear it up.  I really enjoyed the Excel integration demo.  It was very cool watching PowerShell build the spreadsheet in real-time.  I must look into this more!  On a side note, I am jealous of Dan’s hair.  Fabulous hair! Brent’s session showed us how to quickly gather information about a server that you will be taking over database administration duties for.  He wrote a script to do a fast health check and then later wrapped it into a stored procedure, sp_Blitz.  I can’t wait to use this at my work even on systems where I’ve been the primary DBA for years, maybe there’s something I’ve overlooked.  We are using EPM to help standardize our environment and uncover problems, but sp_Blitz will definitely still help us out.  He even provides a cloud-based update feature, sp_BlitzUpdate, for sp_Blitz so you don’t have to constantly update it when he makes a change.  I think I’ll utilize his update code for some other challenges that we face at my work.

    Read the article

  • SQL SERVER – Last Two Days to Get FREE Book – Joes 2 Pros Certification 70-433

    - by pinaldave
    Earlier this week we announced that we will be giving away FREE SQL Wait Stats book to everybody who will get SQL Server Joes 2 Pros Combo Kit. We had a fantastic response to the contest. We got an overwhelming response to the offer. We knew there would be a great response but we want to honestly say thank you to all of you for making it happen. Rick and I want to make sure that we express our special thanks to all of you who are reading our books. The offer is still on and there are two more days to avail this offer. We want to make sure that everybody who buys our most selling combo kits, we will send our other most popular SQL Wait Stats book. Please read all the details of the offer here. The books are great resources for anyone who wants to learn SQL Server from fundamentals and eventually go on the certification path of 70-433. Exam 70-433 contains following important subject and the book covers the subject of fundamental. If you are taking the exam or not taking the exam – this book is for every SQL Developer to learn the subject from fundamentals.  Create and alter tables. Create and alter views. Create and alter indexes. Create and modify constraints. Implement data types. Implement partitioning solutions. Create and alter stored procedures. Create and alter user-defined functions (UDFs). Create and alter DML triggers. Create and alter DDL triggers. Create and deploy CLR-based objects. Implement error handling. Manage transactions. Query data by using SELECT statements. Modify data by using INSERT, UPDATE, and DELETE statements. Return data by using the OUTPUT clause. Modify data by using MERGE statements. Implement aggregate queries. Combine datasets. INTERSECT, EXCEPT Implement subqueries. Implement CTE (common table expression) queries. Apply ranking functions. Control execution plans. Manage international considerations. Integrate Database Mail. Implement full-text search. Implement scripts by using Windows PowerShell and SQL Server Management Objects (SMOs). Implement Service Broker solutions. Track data changes. Data capture Retrieve relational data as XML. Transform XML data into relational data. Manage XML data. Capture execution plans. Collect output from the Database Engine Tuning Advisor. Collect information from system metadata. Availability of Book USA - Amazon | India - Flipkart | Indiaplaza Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Joes 2 Pros, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

    Read the article

  • WebLogic Server Performance and Tuning: Part II - Thread Management

    - by Gokhan Gungor
    WebLogic Server, like any other java application server, provides resources so that your applications use them to provide services. Unfortunately none of these resources are unlimited and they must be managed carefully. One of these resources is threads which are pooled to provide better throughput and performance along with the fast response time and to avoid deadlocks. Threads are execution points that WebLogic Server delivers its power and execute work. Managing threads is very important because it may affect the overall performance of the entire system. In previous releases of WebLogic Server 9.0 we had multiple execute queues and user defined thread pools. There were different queues for different type of work which had fixed number of execute threads.  Tuning of this thread pools and finding the proper number of threads was time consuming which required many trials. WebLogic Server 9.0 and the following releases use a single thread pool and a single priority-based execute queue. All type of work is executed in this single thread pool. Its size (thread count) is automatically decreased or increased (self-tuned). The new “self-tuning” system simplifies getting the proper number of threads and utilizing them.Work manager allows your applications to run concurrently in multiple threads. Work manager is a mechanism that allows you to manage and utilize threads and create rules/guidelines to follow when assigning requests to threads. We can set a scheduling guideline or priority a request with a work manager and then associate this work manager with one or more applications. At run-time, WebLogic Server uses these guidelines to assign pending work/requests to execution threads. The position of a request in the execute queue is determined by its priority. There is a default work manager that is provided. The default work manager should be sufficient for most applications. However there can be cases you want to change this default configuration. Your application(s) may be providing services that need mixture of fast response time and long running processes like batch updates. However wrong configuration of work managers can lead a performance penalty while expecting improvement.We can define/configure work managers at;•    Domain Level: config.xml•    Application Level: weblogic-application.xml •    Component Level: weblogic-ejb-jar.xml or weblogic.xml(For a specific web application use weblogic.xml)We can use the following predefined rules/constraints to manage the work;•    Fair Share Request Class: Specifies the average thread-use time required to process requests. The default is 50.•    Response Time Request Class: Specifies a response time goal in milliseconds.•    Context Request Class: Assigns request classes to requests based on context information.•    Min Threads Constraint: Limits the number of concurrent threads executing requests.•    Max Threads Constraint: Guarantees the number of threads the server will allocate to requests.•    Capacity Constraint: Causes the server to reject requests only when it has reached its capacity. Let’s create a work manager for our application for a long running work.Go to WebLogic console and select Environment | Work Managers from the domain structure tree. Click New button and select Work manager and click next. Enter the name for the work manager and click next. Then select the managed server instances(s) or clusters from available targets (the one that your long running application is deployed) and finish. Click on MyWorkManager, and open the Configuration tab and check Ignore Stuck Threads and save. This will prevent WebLogic to tread long running processes (that is taking more than a specified time) as stuck and enable to finish the process.

    Read the article

  • SSIS Debugging Tip: Using Data Viewers

    - by Jim Giercyk
    When you have an SSIS package error, it is often very helpful to see the data records that are causing the problem.  After all, if your input has 50,000 records and 1 of them has corrupt data, it can be a chore.  Your execution results will tell you which column contains the bad data, but not which record…..enter the Data Viewer. In this scenario I have created a truncation error.  The input length of [lastname] is 50, but the output table has a length of 15.  When it runs, at least one of the records causes the package to fail.     Now what?  We can tell from our execution results that there is a problem with [lastname], but we have no idea WHICH record?     Let’s identify the row that is actually causing the problem.  First, we grab the oft’ forgotten Row Count shape from our toolbar and connect it to the error output from our input query.  Remember that in order to intercept errors with the error output, you must redirect them.     The Row Count shape requires 1 integer variable.  For our purposes, we will not reference the variable, but it is still required in order for the package to run.  Typically we would use the variable to hold the number of rows in the table and refer back to it later in our process.  We are simply using the Row Count as a “Dead End” for errors.  I called my variable RowCounter.  To create a variable, with no shapes selected, right-click on the background and choose Variable.     Once we have setup the Row Count shape, we can right-click on the red line (error output) from the query, and select Data Viewers.  In the popup, we click the add button and we will see this:     There are other fancier options we can play with, but for now we just want to view the output in a grid.  WE select Grid, then click OK on all of the popup windows to shut them down.  We should now see a grid with a pair of glasses on the error output line.     So, we are ready to catch the error output in a grid and see that is causing the problem!  This time when we run the package, it does not fail because we directed the error to the Row Count.  We also get a popup window showing the error record in a grid.  If there were multiple errors we would see them all.     Indeed, the [lastname] column is longer than 15 characters.  Notice the last column in the grid, [Error Code – Description].  We knew this was a truncation error before we added the grid, but if you have worked with SSIS for any length of time, you know that some errors are much more obscure.  The description column can be very useful under those circumstances! Data viewers can be used any time we want to see the data that is actually in the pipeline;  they stop the package temporarily until we shut them.  Also remember that the Row Count shape can be used as a “Dead End”.  It is useful during development when we want to see the output from a dataflow, but don’t want to update a table or file with the data.  Data viewers are an invaluable tool for both development and debugging.  Just remember to REMOVE THEM before putting your package into production

    Read the article

  • How the SPARC T4 Processor Optimizes Throughput Capacity: A Case Study

    - by Ruud
    This white paper demonstrates the architected latency hiding features of Oracle’s UltraSPARC T2+ and SPARC T4 processors That is the first sentence from this technical white paper, but what does it exactly mean? Let's consider a very simple example, the computation of a = b + c. This boils down to the following (pseudo-assembler) instructions that need to be executed: load @b, r1 load @c, r2 add r1,r2,r3 store r3, @a The first two instructions load variables b and c from an address in memory (here symbolized by @b and @c respectively). These values go into registers r1 and r2. The third instruction adds the values in r1 and r2. The result goes into register r3. The fourth instruction stores the contents of r3 into the memory address symbolized by @a. If we're lucky, both b and c are in a nearby cache and the load instructions only take a few processor cycles to execute. That is the good case, but what if b or c, or both, have to come from very far away? Perhaps both of them are in the main memory and then it easily takes hundreds of cycles for the values to arrive in the registers. Meanwhile the processor is doing nothing and simply waits for the data to arrive. Actually, it does something. It burns cycles while waiting. That is a waste of time and energy. Why not use these cycles to execute instructions from another application or thread in case of a parallel program? That is exactly what latency hiding on the SPARC T-Series processors does. It is a hardware feature totally transparent to the user and application. As soon as there is a delay in the execution, the hardware uses these otherwise idle cycles to execute instructions from another process. As a result, the throughput capacity of the system improves because idle cycles are no longer wasted and therefore more jobs can be run per unit of time. This feature has been in the SPARC T-series from the beginning, so why this paper? The difference with previous publications on this topic is in the amount of detail given. How this all works under the hood is fully explained using two example programs. Starting from the assembly language instructions, it is demonstrated in what way these programs execute. To really see what is happening we go down to the processor pipeline level, where the gaps in the execution are, and show in what way these idle cycles are filled by other copies of the same program running simultaneously. Both the SPARC T4 as well as the older UltraSPARC T2+ processor are covered. You may wonder why the UltraSPARC T2+ is included. The focus of this work is on the SPARC T4 processor, but to explain the basic concept of latency hiding at this very low level, we start with the UltraSPARC T2+ processor because it is architecturally a much simpler design. From the single issue, in-order pipelines of this processor we then shift gears and cover how this all works on the much more advanced dual issue, out-of-order architecture of the T4. The analysis and performance experiments have been conducted on both processors. The results depend on the processor, but in all cases the theoretical estimates are confirmed by the experiments. If you're interested to read a lot more about this and find out how things really work under the hood, you can download a copy of the paper here. A paper like this could not have been produced without the help of several other people. I want to thank the co-author of this paper, Jared Smolens, for his very valuable contributions and our highly inspiring discussions. I'm also indebted to Thomas Nau (Ulm University, Germany), Shane Sigler and Mark Woodyard (both at Oracle) for their feedback on earlier versions of this paper. Karen Perkins (Perkins Technical Writing and Editing) and Rick Ramsey at Oracle were very helpful in providing editorial and publishing assistance.

    Read the article

< Previous Page | 48 49 50 51 52 53 54 55 56 57 58 59  | Next Page >