Search Results

Search found 6053 results on 243 pages for 'usage'.

Page 119/243 | < Previous Page | 115 116 117 118 119 120 121 122 123 124 125 126  | Next Page >

• Real tortoises keep it slow and steady. How about the backups?

  - by Maria Zakourdaev

    … Four tortoises were playing in the backyard when they decided they needed hibiscus flower snacks. They pooled their money and sent the smallest tortoise out to fetch the snacks. Two days passed and there was no sign of the tortoise. "You know, she is taking a lot of time", said one of the tortoises. A little voice from just out side the fence said, "If you are going to talk that way about me I won't go." Is it too much to request from the quite expensive 3rd party backup tool to be a way faster than the SQL server native backup? Or at least save a respectable amount of storage by producing a really smaller backup files?  By saying “really smaller”, I mean at least getting a file in half size. After Googling the internet in an attempt to understand what other “sql people” are using for database backups, I see that most people are using one of three tools which are the main players in SQL backup area:  LiteSpeed by Quest SQL Backup by Red Gate SQL Safe by Idera The feedbacks about those tools are truly emotional and happy. However, while reading the forums and blogs I have wondered, is it possible that many are accustomed to using the above tools since SQL 2000 and 2005.  This can easily be understood due to the fact that a 300GB database backup for instance, using regular a SQL 2005 backup statement would have run for about 3 hours and have produced ~150GB file (depending on the content, of course).  Then you take a 3rd party tool which performs the same backup in 30 minutes resulting in a 30GB file leaving you speechless, you run to management persuading them to buy it due to the fact that it is definitely worth the price. In addition to the increased speed and disk space savings you would also get backup file encryption and virtual restore -  features that are still missing from the SQL server. But in case you, as well as me, don’t need these additional features and only want a tool that performs a full backup MUCH faster AND produces a far smaller backup file (like the gain you observed back in SQL 2005 days) you will be quite disappointed. SQL Server backup compression feature has totally changed the market picture. Medium size database. Take a look at the table below, check out how my SQL server 2008 R2 compares to other tools when backing up a 300GB database. It appears that when talking about the backup speed, SQL 2008 R2 compresses and performs backup in similar overall times as all three other tools. 3rd party tools maximum compression level takes twice longer. Backup file gain is not that impressive, except the highest compression levels but the price that you pay is very high cpu load and much longer time. Only SQL Safe by Idera was quite fast with it’s maximum compression level but most of the run time have used 95% cpu on the server. Note that I have used two types of destination storage, SATA 11 disks and FC 53 disks and, obviously, on faster storage have got my backup ready in half time. Looking at the above results, should we spend money, bother with another layer of complexity and software middle-man for the medium sized databases? I’m definitely not going to do so.  Very large database As a next phase of this benchmark, I have moved to a 6 terabyte database which was actually my main backup target. Note, how multiple files usage enables the SQL Server backup operation to use parallel I/O and remarkably increases it’s speed, especially when the backup device is heavily striped. SQL Server supports a maximum of 64 backup devices for a single backup operation but the most speed is gained when using one file per CPU, in the case above 8 files for a 2 Quad CPU server. The impact of additional files is minimal.  However, SQLsafe doesn’t show any speed improvement between 4 files and 8 files. Of course, with such huge databases every half percent of the compression transforms into the noticeable numbers. Saving almost 470GB of space may turn the backup tool into quite valuable purchase. Still, the backup speed and high CPU are the variables that should be taken into the consideration. As for us, the backup speed is more critical than the storage and we cannot allow a production server to sustain 95% cpu for such a long time. Bottomline, 3rd party backup tool developers, we are waiting for some breakthrough release. There are a few unanswered questions, like the restore speed comparison between different tools and the impact of multiple backup files on restore operation. Stay tuned for the next benchmarks.    Benchmark server: SQL Server 2008 R2 sp1 2 Quad CPU Database location: NetApp FC 15K Aggregate 53 discs Backup statements: No matter how good that UI is, we need to run the backup tasks from inside of SQL Server Agent to make sure they are covered by our monitoring systems. I have used extended stored procedures (command line execution also is an option, I haven’t noticed any impact on the backup performance). SQL backup LiteSpeed SQL Backup SQL safe backup database <DBNAME> to disk= '\\<networkpath>\par1.bak' , disk= '\\<networkpath>\par2.bak', disk= '\\<networkpath>\par3.bak' with format, compression EXECUTE master.dbo.xp_backup_database @database = N'<DBName>', @backupname= N'<DBName> full backup', @desc = N'Test', @compressionlevel=8, @filename= N'\\<networkpath>\par1.bak', @filename= N'\\<networkpath>\par2.bak', @filename= N'\\<networkpath>\par3.bak', @init = 1 EXECUTE master.dbo.sqlbackup '-SQL "BACKUP DATABASE <DBNAME> TO DISK= ''\\<networkpath>\par1.sqb'', DISK= ''\\<networkpath>\par2.sqb'', DISK= ''\\<networkpath>\par3.sqb'' WITH DISKRETRYINTERVAL = 30, DISKRETRYCOUNT = 10, COMPRESSION = 4, INIT"' EXECUTE master.dbo.xp_ss_backup @database = 'UCMSDB', @filename = '\\<networkpath>\par1.bak', @backuptype = 'Full', @compressionlevel = 4, @backupfile = '\\<networkpath>\par2.bak', @backupfile = '\\<networkpath>\par3.bak' If you still insist on using 3rd party tools for the backups in your production environment with maximum compression level, you will definitely need to consider limiting cpu usage which will increase the backup operation time even more: RedGate : use THREADPRIORITY option ( values 0 – 6 ) LiteSpeed : use  @throttle ( percentage, like 70%) SQL safe :  the only thing I have found was @Threads option.   Yours, Maria

  Read the article

• ANTS CLR and Memory Profiler In Depth Review (Part 2 of 2 &ndash; Memory Profiler)

  - by ToStringTheory

  One of the things that people might not know about me, is my obsession to make my code as efficient as possible. Many people might not realize how much of a task or undertaking that this might be, but it is surely a task as monumental as climbing Mount Everest, except this time it is a challenge for the mind… In trying to make code efficient, there are many different factors that play a part – size of project or solution, tiers, language used, experience and training of the programmer, technologies used, maintainability of the code – the list can go on for quite some time. I spend quite a bit of time when developing trying to determine what is the best way to implement a feature to accomplish the efficiency that I look to achieve. One program that I have recently come to learn about – Red Gate ANTS Performance (CLR) and Memory profiler gives me tools to accomplish that job more efficiently as well. In this review, I am going to cover some of the features of the ANTS memory profiler set by compiling some hideous example code to test against. Notice As a member of the Geeks With Blogs Influencers program, one of the perks is the ability to review products, in exchange for a free license to the program. I have not let this affect my opinions of the product in any way, and Red Gate nor Geeks With Blogs has tried to influence my opinion regarding this product in any way. Introduction – Part 2 In my last post, I reviewed the feature packed Red Gate ANTS Performance Profiler.  Separate from the Red Gate Performance Profiler is the Red Gate ANTS Memory Profiler – a simple, easy to use utility for checking how your application is handling memory management…  A tool that I wish I had had many times in the past.  This post will be focusing on the ANTS Memory Profiler and its tool set. The memory profiler has a large assortment of features just like the Performance Profiler, with the new session looking nearly exactly alike: ANTS Memory Profiler Memory profiling is not something that I have to do very often…  In the past, the few cases I’ve had to find a memory leak in an application I have usually just had to trace the code of the operations being performed to look for oddities…  Sadly, I have come across more undisposed/non-using’ed IDisposable objects, usually from ADO.Net than I would like to ever see.  Support is not fun, however using ANTS Memory Profiler makes this task easier.  For this round of testing, I am going to use the same code from my previous example, using the WPF application. This time, I will choose the ‘Profile Memory’ option from the ANTS menu in Visual Studio, which launches the solution in its currently configured state/start-up project, and then launches the ANTS Memory Profiler to help.  It prepopulates all of the fields with the current project information, and all I have to do is select the ‘Start Profiling’ option. When the window comes up, it is actually quite barren, just giving ideas on how to work the profiler.  You start by getting to the point in your application that you want to profile, and then taking a ‘Memory Snapshot’.  This performs a full garbage collection, and snapshots the managed heap.  Using the same WPF app as before, I will go ahead and take a snapshot now. As you can see, ANTS is already giving me lots of information regarding the snapshot, however this is just a snapshot.  The whole point of the profiler is to perform an action, usually one where a memory problem is being noticed, and then take another snapshot and perform a diff between them to see what has changed.  I am going to go ahead and generate 5000 primes, and then take another snapshot: As you can see, ANTS is already giving me a lot of new information about this snapshot compared to the last.  Information such as difference in memory usage, fragmentation, class usage, etc…  If you take more snapshots, you can use the dropdown at the top to set your actual comparison snapshots. If you beneath the timeline, you will see a breadcrumb trail showing how best to approach profiling memory using ANTS.  When you first do the comparison, you start on the Summary screen.  You can either use the charts at the bottom, or switch to the class list screen to get to the next step.  Here is the class list screen: As you can see, it lists information about all of the instances between the snapshots, as well as at the bottom giving you a way to filter by telling ANTS what your problem is.  I am going to go ahead and select the Int16[] to look at the Instance Categorizer Using the instance categorizer, you can travel backwards to see where all of the instances are coming from.  It may be hard to see in this image, but hopefully the lightbox (click on it) will help: I can see that all of these instances are rooted to the application through the UI TextBlock control.  This image will probably be even harder to see, however using the ‘Instance Retention Graph’, you can trace an objects memory inheritance up the chain to see its roots as well.  This is a simple example, as this is simply a known element.  Usually you would be profiling an actual problem, and comparing those differences.  I know in the past, I have spotted a problem where a new context was created per page load, and it was rooted into the application through an event.  As the application began to grow, performance and reliability problems started to emerge.  A tool like this would have been a great way to identify the problem quickly. Overview Overall, I think that the Red Gate ANTS Memory Profiler is a great utility for debugging those pesky leaks.  3 Biggest Pros: Easy to use interface with lots of options for configuring profiling session Intuitive and helpful interface for drilling down from summary, to instance, to root graphs ANTS provides an API for controlling the profiler. Not many options, but still helpful. 2 Biggest Cons: Inability to automatically snapshot the memory by interval Lack of complete integration with Visual Studio via an extension panel Ratings Ease of Use (9/10) – I really do believe that they have brought simplicity to the once difficult task of memory profiling.  I especially liked how it stepped you further into the drilldown by directing you towards the best options. Effectiveness (10/10) – I believe that the profiler does EXACTLY what it purports to do.  Features (7/10) – A really great set of features all around in the application, however, I would like to see some ability for automatically triggering snapshots based on intervals or framework level items such as events. Customer Service (10/10) – My entire experience with Red Gate personnel has been nothing but good.  their people are friendly, helpful, and happy! UI / UX (9/10) – The interface is very easy to get around, and all of the options are easy to find.  With a little bit of poking around, you’ll be optimizing Hello World in no time flat! Overall (9/10) – Overall, I am happy with the Memory Profiler and its features, as well as with the service I received when working with the Red Gate personnel.  Thank you for reading up to here, or skipping ahead – I told you it would be shorter!  Please, if you do try the product, drop me a message and let me know what you think!  I would love to hear any opinions you may have on the product. Code Feel free to download the code I used above – download via DropBox

  Read the article

• Different Not Automatically Implies Better

  - by Alois Kraus

  Originally posted on: http://geekswithblogs.net/akraus1/archive/2013/11/05/154556.aspxRecently I was digging deeper why some WCF hosted workflow application did consume quite a lot of memory although it did basically only load a xaml workflow. The first tool of choice is Process Explorer or even better Process Hacker (has more options and the best feature copy&paste does work). The three most important numbers of a process with regards to memory are Working Set, Private Working Set and Private Bytes. Working set is the currently consumed physical memory (parts can be shared between processes e.g. loaded dlls which are read only) Private Working Set is the physical memory needed by this process which is not shareable Private Bytes is the number of non shareable which is only visible in the current process (e.g. all new, malloc, VirtualAlloc calls do create private bytes) When you have a bigger workflow it can consume under 64 bit easily 500MB for a 1-2 MB xaml file. This does not look very scalable. Under 64 bit the issue is excessive private bytes consumption and not the managed heap. The picture is quite different for 32 bit which looks a bit strange but it seems that the hosted VB compiler is a lot less memory hungry under 32 bit. I did try to repro the issue with a medium sized xaml file (400KB) which does contain 1000 variables and 1000 if which can be represented by C# code like this: string Var1; string Var2; ... string Var1000; if (!String.IsNullOrEmpty(Var1) ) { Console.WriteLine(“Var1”); } if (!String.IsNullOrEmpty(Var2) ) { Console.WriteLine(“Var2”); } ....   Since WF is based on VB.NET expressions you are bound to the hosted VB.NET compiler which does result in (x64) 140 MB of private bytes which is ca. 140 KB for each if clause which is quite a lot if you think about the actually present functionality. But there is hope. .NET 4.5 does allow now C# expressions for WF which is a major step forward for all C# lovers. I did create some simple patcher to “cross compile” my xaml to C# expressions. Lets look at the result: C# Expressions VB Expressions x86 x86 On my home machine I have only 32 bit which gives you quite exactly half of the memory consumption under 64 bit. C# expressions are 10 times more memory hungry than VB.NET expressions! I wanted to do more with less memory but instead it did consume a magnitude more memory. That is surprising to say the least. The workflow does initialize in about the same time under x64 and x86 where the VB code does it in 2s whereas the C# version needs 18s. Also nearly ten times slower. That is a too high price to pay for any bigger sized xaml workflow to convert from VB.NET to C# expressions. If I do reduce the number of expressions to 500 then it does need 400MB which is about half of the memory. It seems that the cost per if does rise linear with the number of total expressions in a xaml workflow.  Expression Language Cost per IF Startup Time C# 1000 Ifs x64 1,5 MB 18s C# 500 Ifs x64 750 KB 9s VB 1000 Ifs x64 140 KB 2s VB 500 Ifs x64 70 KB 1s Now we can directly compare two MS implementations. It is clear that the VB.NET compiler uses the same underlying structure but it has much higher offset compared to the highly inefficient C# expression compiler. I have filed a connect bug here with a harsher wording about recent advances in memory consumption. The funniest thing is that one MS employee did give an Azure AppFabric demo around early 2011 which was so slow that he needed to investigate with xperf. He was after startup time and the call stacks with regards to VB.NET expression compilation were remarkably similar. In fact I only found this post by googling for parts of my call stacks. … “C# expressions will be coming soon to WF, and that will have different performance characteristics than VB” … What did he know Jan 2011 what I did no know until today? ;-). He knew that C# expression will come but that they will not be automatically have better footprint. It is about time to fix that. In its current state C# expressions are not usable for bigger workflows. That also explains the headline for today. You can cheat startup time by prestarting workflows so that the demo looks nice and snappy but it does hurt scalability a lot since you do need much more memory than necessary. I did find the stacks by enabling virtual allocation tracking within XPerf which is still the best tool out there. But first you need to look at your process to check where the memory is hiding: For the C# Expression compiler you do not need xperf. You can directly dump the managed heap and check with a profiler of your choice. But if the allocations are happening on the Private Data ( VirtualAlloc ) you can find it with xperf. There is a nice video on channel 9 explaining VirtualAlloc tracking it in greater detail. If your data allocations are on the Heap it does mean that the C/C++ runtime did create a heap for you where all malloc, new calls do allocate from it. You can enable heap tracing with xperf and full call stack support as well which is doable via xperf like it is shown also on channel 9. Or you can use WPRUI directly: To make “Heap Usage” it work you need to set for your executable the tracing flags (before you start it). For example devenv.exe HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\devenv.exe DWORD TracingFlags 1 Do not forget to disable it after you did complete profiling the process or it will impact the startup time quite a lot. You can with xperf attach directly to a running process and collect heap allocation information from a gone wild process. Very handy if you need to find out what a process was doing which has arrived in a funny state. “VirtualAlloc usage” does work without explicitly enabling stuff for a specific process and is always on machine wide. I had issues on my Windows 7 machines with the call stack collection and the latest Windows 8.1 Performance Toolkit. I was told that WPA from Windows 8.0 should work fine but I do not want to downgrade.

  Read the article

• Java EE 7 Survey Results!

  - by reza_rahman

  On November 8th, the Java EE EG posted a survey to gather broad community feedback on a number of critical open issues. For reference, you can find the original survey here. We kept the survey open for about three weeks until November 30th. To our delight, over 1100 developers took time out of their busy lives to let their voices be heard! The results of the survey were sent to the EG on December 12th. The subsequent EG discussion is available here. The exact summary sent to the EG is available here. We would like to take this opportunity to thank each and every one the individuals who took the survey. It is very appreciated, encouraging and worth it's weight in gold. In particular, I tried to capture just some of the high-quality, intelligent, thoughtful and professional comments in the summary to the EG. I highly encourage you to continue to stay involved, perhaps through the Adopt-a-JSR program. We would also like to sincerely thank java.net, JavaLobby, TSS and InfoQ for helping spread the word about the survey. Below is a brief summary of the results... APIs to Add to Java EE 7 Full/Web Profile The first question asked which of the four new candidate APIs (WebSocket, JSON-P, JBatch and JCache) should be added to the Java EE 7 Full and Web profile respectively. As the following graph shows, there was significant support for adding all the new APIs to the full profile: Support is relatively the weakest for Batch 1.0, but still good. A lot of folks saw WebSocket 1.0 as a critical technology with comments such as this one: "A modern web application needs Web Sockets as first class citizens" While it is clearly seen as being important, a number of commenters expressed dissatisfaction with the lack of a higher-level JSON data binding API as illustrated by this comment: "How come we don't have a Data Binding API for JSON" JCache was also seen as being very important as expressed with comments like: "JCache should really be that foundational technology on which other specs have no fear to depend on" The results for the Web Profile is not surprising. While there is strong support for adding WebSocket 1.0 and JSON-P 1.0 to the Web Profile, support for adding JCache 1.0 and Batch 1.0 is relatively weak. There was actually significant opposition to adding Batch 1. 0 (with 51.8% casting a 'No' vote). Enabling CDI by Default The second question asked was whether CDI should be enabled in Java EE environments by default. A significant majority of 73.3% developers supported enabling CDI, only 13.8% opposed. Comments such as these two reflect a strong general support for CDI as well as a desire for better Java EE alignment with CDI: "CDI makes Java EE quite valuable!" "Would prefer to unify EJB, CDI and JSF lifecycles" There is, however, a palpable concern around the performance impact of enabling CDI by default as exemplified by this comment: "Java EE projects in most cases use CDI, hence it is sensible to enable CDI by default when creating a Java EE application. However, there are several issues if CDI is enabled by default: scanning can be slow - not all libs use CDI (hence, scanning is not needed)" Another significant concern appears to be around backwards compatibility and conflict with other JSR 330 implementations like Spring: "I am leaning towards yes, however can easily imagine situations where errors would be caused by automatically activating CDI, especially in cases of backward compatibility where another DI engine (such as Spring and the like) happens to use the same mechanics to inject dependencies and in that case there would be an overlap in injections and probably an uncertain outcome" Some commenters such as this one attempt to suggest solutions to these potential issues: "If you have Spring in use and use javax.inject.Inject then you might get some unexpected behavior that could be equally confusing. I guess there will be a way to switch CDI off. I'm tempted to say yes but am cautious for this reason" Consistent Usage of @Inject The third question was around using CDI/JSR 330 @Inject consistently vs. allowing JSRs to create their own injection annotations. A slight majority of 53.3% developers supported using @Inject consistently across JSRs. 28.8% said using custom injection annotations is OK, while 18.0% were not sure. The vast majority of commenters were strongly supportive of CDI and general Java EE alignment with CDI as illistrated by these comments: "Dependency Injection should be standard from now on in EE. It should use CDI as that is the DI mechanism in EE and is quite powerful. Having a new JSR specific DI mechanism to deal with just means more reflection, more proxies. JSRs should also be constructed to allow some of their objects Injectable. @Inject @TransactionalCache or @Inject @JMXBean etc...they should define the annotations and stereotypes to make their code less procedural. Dog food it. If there is a shortcoming in CDI for a JSR fix it and we will all be grateful" "We're trying to make this a comprehensive platform, right? Injection should be a fundamental part of the platform; everything else should build on the same common infrastructure. Each-having-their-own is just a recipe for chaos and having to learn the same thing 10 different ways" Expanding the Use of @Stereotype The fourth question was about expanding CDI @Stereotype to cover annotations across Java EE beyond just CDI. A significant majority of 62.3% developers supported expanding the use of @Stereotype, only 13.3% opposed. A majority of commenters supported the idea as well as the theme of general CDI/Java EE alignment as expressed in these examples: "Just like defining new types for (compositions of) existing classes, stereotypes can help make software development easier" "This is especially important if many EJB services are decoupled from the EJB component model and can be applied via individual annotations to Java EE components. @Stateless is a nicely compact annotation. Code will not improve if that will have to be applied in the future as @Transactional, @Pooled, @Secured, @Singlethreaded, @...." Some, however, expressed concerns around increased complexity such as this commenter: "Could be very convenient, but I'm afraid if it wouldn't make some important class annotations less visible" Expanding Interceptor Use The final set of questions was about expanding interceptors further across Java EE... A very solid 96.3% of developers wanted to expand interceptor use to all Java EE components. 35.7% even wanted to expand interceptors to other Java EE managed classes. Most developers (54.9%) were not sure if there is any place that injection is supported that should not support interceptors. 32.8% thought any place that supports injection should also support interceptors. Only 12.2% were certain that there are places where injection should be supported but not interceptors. The comments reflected the diversity of opinions, generally supportive of interceptors: "I think interceptors are as fundamental as injection and should be available anywhere in the platform" "The whole usage of interceptors still needs to take hold in Java programming, but it is a powerful technology that needs some time in the Sun. Basically it should become part of Java SE, maybe the next step after lambas?" A distinct chain of thought separated interceptors from filters and listeners: "I think that the Servlet API already provides a rich set of possibilities to hook yourself into different Servlet container events. I don't find a need to 'pollute' the Servlet model with the Interceptors API"

  Read the article

• Data Source Connection Pool Sizing

  - by Steve Felts

  Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* 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:10.0pt; font-family:"Times New Roman","serif";} One of the most time-consuming procedures of a database application is establishing a connection. The connection pooling of the data source can be used to minimize this overhead.  That argues for using the data source instead of accessing the database driver directly. Configuring the size of the pool in the data source is somewhere between an art and science – this article will try to move it closer to science.  From the beginning, WLS data source has had an initial capacity and a maximum capacity configuration values.  When the system starts up and when it shrinks, initial capacity is used.  The pool can grow to maximum capacity.  Customers found that they might want to set the initial capacity to 0 (more on that later) but didn’t want the pool to shrink to 0.  In WLS 10.3.6, we added minimum capacity to specify the lower limit to which a pool will shrink.  If minimum capacity is not set, it defaults to the initial capacity for upward compatibility.   We also did some work on the shrinking in release 10.3.4 to reduce thrashing; the algorithm that used to shrink to the maximum of the currently used connections or the initial capacity (basically the unused connections were all released) was changed to shrink by half of the unused connections. The simple approach to sizing the pool is to set the initial/minimum capacity to the maximum capacity.  Doing this creates all connections at startup, avoiding creating connections on demand and the pool is stable.  However, there are a number of reasons not to take this simple approach. When WLS is booted, the deployment of the data source includes synchronously creating the connections.  The more connections that are configured in initial capacity, the longer the boot time for WLS (there have been several projects for parallel boot in WLS but none that are available).  Related to creating a lot of connections at boot time is the problem of logon storms (the database gets too much work at one time).   WLS has a solution for that by setting the login delay seconds on the pool but that also increases the boot time. There are a number of cases where it is desirable to set the initial capacity to 0.  By doing that, the overhead of creating connections is deferred out of the boot and the database doesn’t need to be available.  An application may not want WLS to automatically connect to the database until it is actually needed, such as for some code/warm failover configurations. There are a number of cases where minimum capacity should be less than maximum capacity.  Connections are generally expensive to keep around.  They cause state to be kept on both the client and the server, and the state on the backend may be heavy (for example, a process).  Depending on the vendor, connection usage may cost money.  If work load is not constant, then database connections can be freed up by shrinking the pool when connections are not in use.  When using Active GridLink, connections can be created as needed according to runtime load balancing (RLB) percentages instead of by connection load balancing (CLB) during data source deployment. Shrinking is an effective technique for clearing the pool when connections are not in use.  In addition to the obvious reason that there times where the workload is lighter,  there are some configurations where the database and/or firewall conspire to make long-unused or too-old connections no longer viable.  There are also some data source features where the connection has state and cannot be used again unless the state matches the request.  Examples of this are identity based pooling where the connection has a particular owner and XA affinity where the connection is associated with a particular RAC node.  At this point, WLS does not re-purpose (discard/replace) connections and shrinking is a way to get rid of the unused existing connection and get a new one with the correct state when needed. So far, the discussion has focused on the relationship of initial, minimum, and maximum capacity.  Computing the maximum size requires some knowledge about the application and the current number of simultaneously active users, web sessions, batch programs, or whatever access patterns are common.  The applications should be written to only reserve and close connections as needed but multiple statements, if needed, should be done in one reservation (don’t get/close more often than necessary).  This means that the size of the pool is likely to be significantly smaller then the number of users.   If possible, you can pick a size and see how it performs under simulated or real load.  There is a high-water mark statistic (ActiveConnectionsHighCount) that tracks the maximum connections concurrently used.  In general, you want the size to be big enough so that you never run out of connections but no bigger.   It will need to deal with spikes in usage, which is where shrinking after the spike is important.  Of course, the database capacity also has a big influence on the decision since it’s important not to overload the database machine.  Planning also needs to happen if you are running in a Multi-Data Source or Active GridLink configuration and expect that the remaining nodes will take over the connections when one of the nodes in the cluster goes down.  For XA affinity, additional headroom is also recommended.  In summary, setting initial and maximum capacity to be the same may be simple but there are many other factors that may be important in making the decision about sizing.

  Read the article

• Best Practice for captcha based protection against D.O.S to Nginx Proxy

  - by user325320

  The idea is explained here In simple words, Nginx Proxy plays the role of load balance and transmits the HTTP/HTTPS requests to servers. If the number of request times within a certain period from an individual IP exceeds a threshold, it will trigger a captcha for the upcoming requests. And the end-user must input the correct captcha code before he can continue to access the site. Do you know any open source / free NGINX module for this usage? I searched on the Internet and here is one of them: https://github.com/snbuback/nginx seems it needs modification. Any suggestion / experience is welcome, thank you

  Read the article

• PHP/APC fatal error, apc_mmap: mmap failed

  - by Sudowned

  I'm seeing some intermittent CPU usage spikes to 100%, sort of correlated to these log entries: [27-Feb-2012 13:29:29] PHP Fatal error: PHP Startup: apc_mmap: mmap failed: in Unknown on line 0 [27-Feb-2012 13:29:30] PHP Fatal error: PHP Startup: apc_mmap: mmap failed: in Unknown on line 0 [27-Feb-2012 13:29:31] PHP Fatal error: PHP Startup: apc_mmap: mmap failed: in Unknown on line 0 [27-Feb-2012 13:29:31] PHP Fatal error: PHP Startup: apc_mmap: mmap failed: in Unknown on line 0 phpinfo() indicates that APC is set up, and as far as I can tell this error doesn't cause visible 500 errors on the live site, which is a WordPress install that gets about 600k views monthly. Google's been unhelpful so far, and I was hoping that someone here had some insight as to what's causing this and how to fix it. Curiously, this error only shows up /usr/local/apache2/logs/error_log and not the error_log for the cpanel-configured site.

  Read the article

• How to resolve "svn: Can't find a temporary directory: Internal error"?

  - by HorusKol

  I have already googled the message, and I have plenty of disk space available on the SVN server (it's about 4% usage of 150 GB). I have noticed that when I try echo $TMPDIR at the command prompt on the SVN server I get nothing. What is making this a little confusing is that I only get this message from one location when I do an svn diff (that I've tested so far) - this error is not coming up when I try from three other computers (one of which is testing against the exact same repository, the other two are different repositories on the same svn server). About the only difference I can see is that the broken working copy is connecting to the server by an IP address where all the others are using a server name (although this resolves over DNS to the same IP Address). I'm hoping that I don't have to scratch the broken working copy and checkout a new one - unfortunately, this is a legacy project and not all changes have been properly revisioned.

  Read the article

• iftop - how to generate text file with its output?

  - by mickula

  iftop is great tool to view almost live bandwidth usage distinguished by source-ip source-port destination-ip destination port. I'm using it to see which client's ip is using most bandwidth. Now I would like to store output somewhere. iftop uses ncurses so iftop > log.txt does not work as expected, result file is not readable. Is there any tool like this which can be used to pipe output to a text file? Thanks for your replies.

  Read the article

• Simple jquery ajax call leaks memory in ie.

  - by Thomas Lane

  I created a web page that makes an ajax call every second. In Internet Explorer 7, it leaks memory badly (20MB in about 15 minutes). The program is very simple. It just runs a javascript function that makes an ajax call. The server returns an empty string, and the javascript does nothing with it. I use setTimout to run the function every second, and I'm using Drip to watch the thing. Here is the source: <html> <head> <script type="text/javascript" src="http://www.google.com/jsapi"></script> <script type="text/javascript"> google.load('jquery', '1.4.2'); google.load('jqueryui', '1.7.2'); </script> <script type="text/javascript"> setTimeout('testJunk()',1000); function testJunk() { $.ajax({ url: 'http://xxxxxxxxxxxxxx/test', // The url returns an empty string dataType: 'html', success: function(data){} }); setTimeout('testJunk()',1000) } </script> </head> <body> Why is memory usage going up? </body> </html> Anyone have an idea how to plug this leak? I have a real application that updates a large table this way, but left unattended will eat up Gigabytes of memory. Okay, so after some good suggestions, I modified the code to: <html> <head> <script type="text/javascript" src="http://www.google.com/jsapi"></script> <script type="text/javascript"> google.load('jquery', '1.4.2'); google.load('jqueryui', '1.7.2'); </script> <script type="text/javascript"> setTimeout(testJunk,1000); function testJunk() { $.ajax({ url: 'http://xxxxxxxxxxxxxx/test', // The url returns an empty string dataType: 'html', success: function(data){setTimeout(testJunk,1000)} }); } </script> </head> <body> Why is memory usage going up? </body> </html> It didn't seem to make any difference though. I'm not doing anything with the DOM, and if I comment out the ajax call, the memory leak stops. So it looks like the leak is entirely in the ajax call. Does jquery ajax inherently create some sort of circular reference, and if so, how can I free it? By the way, it doesn't leak in Firefox. Someone suggested running the test in another VM and see if the results are the same. Rather than setting up another VM, I found a laptop that was running XP Home with IE8. It exhibits the same problem. I tried some older versions of jquery and got better results, but the problem didn't go away entirely until I abandoned ajax in jquery and went with more traditional (and ugly) ajax.

  Read the article

• Server with IIS and Apache - how to SSL encrypt Apache with IIS

  - by GAThrawn

  I have a Windows Server 2003 box already setup and working with IIS 6. IIS is set to serve a site out over both HTTP and HTTPS connections using default ports. For various reasons I need to set Apache up on the same server and it needs to serve its pages to end-users as SSL encrypted HTTPS pages. Neither IIS or Apache are (or are ever likely to be) particularly high traffic or high usage. The way I see it there are two possible ways this could be done. Either export the SSL cert from IIS,set it up in Apache and get Apache to server the HTTPS connections itself over a non-default port. Or use IIS to proxy Apache in some way over it's existing SSL security. What is going to end up easiest to setup, configure, maintain and run? Which is going to work best? Has anyone done this sort of thing before? Any tips or things to look out for?

  Read the article

• HyperV on Domain Controller or DC on HyperV?

  - by Michael Stum

  I want to setup a little fileserver/domain controller/sharepoint server. SharePoint shouldn't run on the DC directly, so I want to use HyperV. But I never used it before, so I wonder: Should I install the Domain Controller and HyperV Role and run 1 VM for SharePoint? Or should I run HyperV server and then 2 servers, one for SharePoint and 1 for DC? Usage is minimal with only 1 user. Hardware will be an Athlon II X3 with 3x2.9 GHz and 4 GB RAM. Operating System will be Server 2008 R2 Standard in all cases.

  Read the article

• procdump on w3wp.exe: Only part of a ReadProcessMemory or WriteProcessMemory request was completed.

  - by JakeS

  I'm having a problem with an IIS application that occasionally spikes up in CPU usage, and am trying to use procdump to get a memory dump for examination. I'm running "procdump.exe -64 -mA 9999" where 9999 is the pid of the process. But every time I do it, I get an error: Only part of a ReadProcessMemory or WriteProcessMemory request was completed. Doing this also recycles the apppool, relieving the CPU spike, so I can't keep trying until I get it right. Does anyone know what is going wrong?

  Read the article

• cscript - Invalid procedure call or argument when running a vbs file

  - by quanta

  I've been trying to use check_time.vbs to check the Windows time. Here's the script: http://pastebin.com/NfUrCAqU The help message could be display: C:\Program Files\NSClient++\scripts>cscript //NoLogo check_time.vbs /? check_time.vbs V1.01 Usage: cscript /NoLogo check_time.vbs serverlist warn crit [biggest] Options: serverlist (required): one or more server names, coma-separated warn (required): warning offset in seconds, can be partial crit (required): critical offset in seconds, can be partial biggest (optional): if multiple servers, else use default least offset Example: cscript /NoLogo check_time.vbs myserver1,myserver2 0.4 5 biggest But I get the following error when running: C:\Program Files\NSClient++\scripts>cscript //NoLogo check_time.vbs 0.asia.pool.ntp.org 20 50 C:\Program Files\NSClient++\scripts\check_time.vbs(53, 1) Microsoft VBScript run time error: Invalid procedure call or argument The screenshot: Manually execute w32tm still works fine: What might be the cause of this?

  Read the article

• Add Scheduled Task to reset search indexes for Exchange 2007

  - by Samosa

  I simply want to run a ResetSearchIndex -force on a schedule. What is the correct usage for the command in the Scheduled Task properties? It seems I would first need to start Powershell, then load the console file or snap-in for Exchange, which one of these is the closest: C:\WINDOWS\system32\WINDOW~2\v1.0\POWERS~1.EXE -"D:\Program Files\Microsoft\Exchange Server\Scripts" ResetSearchIndex.ps1 -force dbname or C:\WINDOWS\system32\WINDOW~2\v1.0\POWERS~1.EXE -PSConsoleFile "D:\Program Files\Microsoft\Exchange Server\bin\exshell.psc1" -noexit -command ".'D:\Program Files\Microsoft\Exchange Server\Scripts' ResetSearchIndex.ps1 -force dbname or C:\WINDOWS\system32\WINDOW~2\v1.0\POWERS~1.EXE -PSConsoleFile "D:\Program Files\Microsoft\Exchange Server\bin\exshell.psc1" -noexit -command ".'D:\Program Files\Microsoft\Exchange Server\Scripts\ResetSearchIndex.ps1' -force dbname

  Read the article

• Which part of the computer needs all the power from the PSU?

  - by Xeoncross

  A couple years ago I was building a new Core 2 Quad system and after reading all the reviews was convinced that I would need at least a 400 watt power supply unit (PSU). I bought a 500W Antec EarthWatts However, last year I bought a Kill-A-Watt power meter to test some things around our house and found that my PC was only using 80W of power while idle! (C2Q, 4GB RAM, SATA HD, & DVD burner) Well, here I am building another computer with a 65watt Core 2 CPU in it and I'm wondering if I can skimp out this time and get a 300watt or so unit since my usage doesn't seem to be what everyone claims it is. I'm sure that the people in the reviews who exhausted 500watt PSU weren't lying - so what is it that uses all that? The high-end dual SLI video cards? Lots of SATA drives? Overclocking?

  Read the article

• VMware ESXi - varying CPU time (CPU reservation)

  - by Tomo

  Hello! I'm running FreeBSD 7.2 under VMware ESXi 3.5. Host has 2 physical CPUs and the BSD box is currently the only running VM. Only one virtual CPU is assigned to the VM. When measuring CPU time of a specific program, I get very different results from time to time. Processor usage is reported differently by VMware, based on the system load. Is it possible to assign a constant share of a physical CPU to specific VM? I would like the CPU time to be more or less much constant. I tried setting CPU reservation when configuring VM in the VMware Infrastructure Client, but the CPU time still varies a lot. Thanks in advance!

  Read the article

• DD-WRT Connection Leak

  - by Nerdfest

  I have DD-WRT installed on a WRT54G v1.1, and a few of the features seem to cause connections to leak. I've configured it for 1024 connections with TCP/UDP timeouts of 180/30. I've tried higher values as well. Anyway, if I use the Bandwidth tab to monitor the bandwidth usage, the number of connections to my workstation reaches about 450. Is this normal? If not, any idea how to get the connections to either not be created, or to drop much faster?

  Read the article

• Disable Windows Key Hotkeys when using Virtualbox

  - by statenjason

  I'm currently running a VirtualBox of Arch Linux with Windows 7 x64 as the host. In Arch, I use dwm for window management. As dwm is heavily dependent on hotkeys, I've used the ALT key as its META key to prevent conflict with the Windows 7 host. However, when using emacs (also heavy hotkey usage) within dwm, there are issues because it's also using ALT for its own META. I'd like to change either dwm or emacs to use the windows key as META, but commands such as Win+L will be captured by the host machine and lock my system. Is there any way to prevent these hotkeys from being triggered while within VirtualBox?

  Read the article

• Munin-cron fails "Nothing to do", possibly a munin.conf problem?

  - by geerlingguy

  I have been working on this for a few hours now, and haven't yet been able to get munin to output the html files/generated graphs of resource usage on my CentOS 5.3 server. Here are some things I run as the munin user, and the results: /usr/share/munin/munin-update --nofork --debug (above works fine, takes ~2.4 seconds to complete) munin-run cpu (And other options/plugins (besides 'cpu'), all work fine and give desired output) munin-cron Fails with: [FATAL] There is nothing to do here, since there are no nodes with any plugins. Please refer to http://munin-monitoring.org/wiki/FAQ_no_graphs at /usr/share/munin/munin-html line 38 I am wondering if, perhaps, the settings in my munin.conf file might be causing a problem. Here's the contents of that file (below): bdir /var/lib/munin/ htmldir /home/archdev/public_html/monitoring logdir /var/log/munin rundir /var/run/munin/ tmpldir /etc/munin/templates [archstl.archstl.org] address 127.0.0.1 use_node_name yes Also, when I run the telnet localhost 4949 command, and list the node's plugins, it returns the default munin list... something seems to be wrong with the munin html creation process. :(

  Read the article

• PHP pages working slow from time to time

  - by user1038179

  I have VPS with limit of 2GB of ram and 8 CPU cores. I have 5 sites on that VPS (one of them is just for testing, no visitors exept me). All 5 sites are image galleries, like wallpaper sites. Last week I noticed problem on one site (main domain, used for name servers, and also with most traffic, visitors). That site has two image galleries, one is old static html gallery made few years ago and another, main, is powered by ZENPhoto CMS. Also I have that same gallery CMS on another two sites on that same VPS (on one running site and on one just for testing site). On other two sites I have diferent PHP driven gallery. Problem is that after some time (it vary from 10 minutes to few hours after apache restart), loading of pages on main site becomes very slow, or I get 503 Service Temporarily Unavailable error. So pages becomes unavailable. But just that part with new CMS gallery, old part of site with static html pages are working fast and just fine. Also other two sites with same CMS gallery and other two with different PHP driven gallery are working fine and fast at the same time. I thought it must be something with CMS on that main site, because other sites are working nice. Then I tryed to open contact and guest book pages on that main site which are outside of that CMS but also PHP pages, and they do not load too, but that same contact php scipts are working on other sites at the same time. So, when site starts to hangs, ONLY PHP generated content is not working, like I said other static pages are working. And, ONLY on that one main site I have problems. Then I need to restart Apache, after restart everything is vorking nice and fast, for some time, than again, just PHP pages on main site are becomming slower. If I do not restart apache that slowness take some time (several minutes, hours, depending ot traffic) and during that time PHP diven content is loading very slow or unavailable on that site. After sime time, on moments everything start to work and is fast again for some time, and again. In hours with more traffic PHP content is loading slowly or it is unavailable, in hours with less traffic it is sometimes fast and sometimes little bit slower than usually. And ones again, only on that main site, and only PHP driven pages, static pages are working fast even in most traffic hours also other sites with even same CMS are working fast. Currently I have about 7000 unique visitors on that site but site worked nice even with 11500 visitors per day. And about 17000 in total visitors on VPS, all sites ( about 3 pages per unique visitor). When site start to slow down sometimes in apache status I can see something like this: mod_fcgid status: Total FastCGI processes: 37 Process: php5 (/usr/local/cpanel/cgi-sys/php5)Pid Active Idle Accesses State 11300 39 28 7 Working 11274 47 28 7 Working 11296 40 29 3 Working 11283 45 30 3 Working 11304 36 31 1 Working 11282 46 32 3 Working 11292 42 33 1 Working 11289 44 34 1 Working 11305 35 35 0 Working 11273 48 36 2 Working 11280 47 39 1 Working 10125 133 40 12 Exiting(communication error) 11294 41 41 1 Exiting(communication error) 11277 47 42 2 Exiting(communication error) 11291 43 43 1 Exiting(communication error) 10187 108 43 10 Exiting(communication error) 10209 95 44 7 Exiting(communication error) 10171 113 44 5 Exiting(communication error) 11275 47 47 1 Exiting(communication error) 10144 125 48 8 Exiting(communication error) 10086 149 48 20 Exiting(communication error) 10212 94 49 5 Exiting(communication error) 10158 118 49 5 Exiting(communication error) 10169 114 50 4 Exiting(communication error) 10105 141 50 16 Exiting(communication error) 10094 146 50 15 Exiting(communication error) 10115 139 51 17 Exiting(communication error) 10213 93 51 9 Exiting(communication error) 10197 103 51 7 Exiting(communication error) Process: php5 (/usr/local/cpanel/cgi-sys/php5)Pid Active Idle Accesses State 7983 1079 2 149 Ready 7979 1079 11 151 Ready Process: php5 (/usr/local/cpanel/cgi-sys/php5)Pid Active Idle Accesses State 7990 1066 0 57 Ready 8001 1031 64 35 Ready 7999 1032 94 29 Ready 8000 1031 91 36 Ready 8002 1029 34 52 Ready Process: php5 (/usr/local/cpanel/cgi-sys/php5)Pid Active Idle Accesses State 7991 1064 29 115 Ready When it is working nicly there is no lines with "Exiting(communication error)" Active and Idle are time active and time since last request, in seconds. Here are system info. Sysem info: Total processors: 8 Processor #1 Vendor GenuineIntel Name Intel(R) Xeon(R) CPU E5440 @ 2.83GHz Speed 88.320 MHz Cache 6144 KB All other seven are the same. System Information Linux vps.nnnnnnnnnnnnnnnnn.nnn 2.6.18-028stab099.3 #1 SMP Wed Mar 7 15:20:22 MSK 2012 x86_64 x86_64 x86_64 GNU/Linux Current Memory Usage total used free shared buffers cached Mem: 8388608 882164 7506444 0 0 0 -/+ buffers/cache: 882164 7506444 Swap: 0 0 0 Total: 8388608 882164 7506444 Current Disk Usage Filesystem Size Used Avail Use% Mounted on /dev/vzfs 100G 34G 67G 34% / none System Details: Running on: Apache/2.2.22 System info: (Unix) mod_ssl/2.2.22 OpenSSL/0.9.8e-fips-rhel5 DAV/2 mod_auth_passthrough/2.1 mod_bwlimited/1.4 FrontPage/5.0.2.2635 mod_fcgid/2.3.6 Powered by: PHP/5.3.10 Current Configuration Default PHP Version (.php files) 5 PHP 5 Handler fcgi PHP 4 Handler suphp Apache suEXEC on Apache Ruid2 off PHP 4 Handler suphp Apache suEXEC on Apache Configuration The following settings have been saved: fileetag: All keepalive: On keepalivetimeout: 3 maxclients: 150 maxkeepaliverequests: 10 maxrequestsperchild: 10000 maxspareservers: 10 minspareservers: 5 root_options: ExecCGI, FollowSymLinks, Includes, IncludesNOEXEC, Indexes, MultiViews, SymLinksIfOwnerMatch serverlimit: 256 serversignature: Off servertokens: Full sslciphersuite: ALL:!ADH:RC4+RSA:+HIGH:+MEDIUM:-LOW:-SSLv2:-EXP:!kEDH startservers: 5 timeout: 30 I hope, I explained my problem nicely. Any help would be nice.

  Read the article

• php-fpm start error

  - by Sujay

  I am using php-fpm. I recently recompiled php for including imap functions. But on php-fpm start it gives the following error: Starting php_fpm Error in argument 1, char 1: no argument for option - Usage: php-cgi [-q] [-h] [-s] [-v] [-i] [-f ] php-cgi [args...] -a Run interactively -C Do not chdir to the script's directory -c | Look for php.ini file in this directory -n No php.ini file will be used -d foo[=bar] Define INI entry foo with value 'bar' -e Generate extended information for debugger/profiler -f Parse . Implies `-q' -h This help -i PHP information -l Syntax check only (lint) -m Show compiled in modules -q Quiet-mode. Suppress HTTP Header output. -s Display colour syntax highlighted source. -v Version number -w Display source with stripped comments and whitespace. -z Load Zend extension ................................... failed What could be the problem? Is it in php-fpm.conf or php.ini.

  Read the article

• Netbook performance - 1.33 GHz vs 1.6/1.66 GHz Atom

  - by Imran

  All new 11" netbooks seem to carry 1.33 GHz Atom Z520 CPU instead of 1.6/1.66 GHz Atom N270/N280. The screen resolution of 11" netbooks make them very appealing, but I'm a bit concerned about their performance as they carry a slower CPU than the 1.6GHz Atom, which isn't a great performer in the first place. Is there any significant difference in performance between 1.33 GHz and 1.6/1.66 GHz Atom processors in day to day usage? Are any of those fast enough to decode 720p x264 video? (When paired with typical Intel GMA platform and software decoder like ffdshow/CoreAVC of course, not with Nvidia Ion platform)

  Read the article

• tmux combine multiple commands to one vi-copy command or tmux command to yank a line

  - by MIkhail

  In tmux, i know we can chain multiple commands to a key by using \; See Here But in vi mode, i want one single key press to go to the beginning of the current line, begin-selection, go to end-of-line, copy-selection. In tmux.conf if i give the following bind-key -t vi-copy 's' start-of-line \; begin-selection \; end-of-line \; copy-selection \; It gives me this : 69: usage: bind-key [-cnr] [-t key-table] key command [arguments] error. Or is there any alternative way to yank the current line in single key.

  Read the article

• Running Java from a Windows batch file causes the batch file to stop

  - by jjkparker

  When I run Java from a Windows .cmd file (Vista 32-bit here), the Java command causes the batch file to stop executing additional commands. For example, this is a simple test.cmd file: java java This should cause Java to print its help message twice. However when I run it in cmd.exe, I get this: C:\>test C:\>java Usage: java [-options] class [args...] (to execute a class) or java [-options] -jar jarfile [args...] (to execute a jar file) where options include: -client to select the "client" VM -server to select the "server" VM ... C:\> The batch file simply exits when Java exits. What's going on here?

  Read the article

< Previous Page | 115 116 117 118 119 120 121 122 123 124 125 126  | Next Page >