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  • Linux 'top' utility widly inaccurate (more so for multi-CPU/core hardware)?

    - by amn
    Hi all. After using 'top' for long time, albeit basically, I have grown to distrust it's '% CPU' column reports. I have a 8-core (quad core Intel i7 920 with hyperthreading) hardware, and see some wild numbers when running a process that should not use more than 5% overall. top happily reports 50%, and I suspect it is not so. My question is, is it a known fact that it's inaccurate when several CPUs/cores are present? I used 'mpstat' from the 'sysstat' package, and it's showings are much more conservative, certainly within my expectations. I did press '1' for 'top' to switch it to show all the core and us/sy/io stats, but the numbers are substantially higher than with 'mpstat'... I know that my expectations can be unfound as well, but my gut feeling tells me 'top' is wrong! :-) The reason I need to know is because the process I am monitoring only guarantees quality of service with CPU usage "less than 80%" (however vague that sounds), and I need to know how much headroom I have left. It's a streaming server.

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  • Oracle MAA Part 1: When One Size Does Not Fit All

    - by JoeMeeks
    The good news is that Oracle Maximum Availability Architecture (MAA) best practices combined with Oracle Database 12c (see video) introduce first-in-the-industry database capabilities that truly make unplanned outages and planned maintenance transparent to users. The trouble with such good news is that Oracle’s enthusiasm in evangelizing its latest innovations may leave some to wonder if we’ve lost sight of the fact that not all database applications are created equal. Afterall, many databases don’t have the business requirements for high availability and data protection that require all of Oracle’s ‘stuff’. For many real world applications, a controlled amount of downtime and/or data loss is OK if it saves money and effort. Well, not to worry. Oracle knows that enterprises need solutions that address the full continuum of requirements for data protection and availability. Oracle MAA accomplishes this by defining four HA service level tiers: BRONZE, SILVER, GOLD and PLATINUM. The figure below shows the progression in service levels provided by each tier. Each tier uses a different MAA reference architecture to deploy the optimal set of Oracle HA capabilities that reliably achieve a given service level (SLA) at the lowest cost.  Each tier includes all of the capabilities of the previous tier and builds upon the architecture to handle an expanded fault domain. Bronze is appropriate for databases where simple restart or restore from backup is ‘HA enough’. Bronze is based upon a single instance Oracle Database with MAA best practices that use the many capabilities for data protection and HA included with every Oracle Enterprise Edition license. Oracle-optimized backups using Oracle Recovery Manager (RMAN) provide data protection and are used to restore availability should an outage prevent the database from being able to restart. Silver provides an additional level of HA for databases that require minimal or zero downtime in the event of database instance or server failure as well as many types of planned maintenance. Silver adds clustering technology - either Oracle RAC or RAC One Node. RMAN provides database-optimized backups to protect data and restore availability should an outage prevent the cluster from being able to restart. Gold raises the game substantially for business critical applications that can’t accept vulnerability to single points-of-failure. Gold adds database-aware replication technologies, Active Data Guard and Oracle GoldenGate, which synchronize one or more replicas of the production database to provide real time data protection and availability. Database-aware replication greatly increases HA and data protection beyond what is possible with storage replication technologies. It also reduces cost while improving return on investment by actively utilizing all replicas at all times. Platinum introduces all of the sexy new Oracle Database 12c capabilities that Oracle staff will gush over with great enthusiasm. These capabilities include Application Continuity for reliable replay of in-flight transactions that masks outages from users; Active Data Guard Far Sync for zero data loss protection at any distance; new Oracle GoldenGate enhancements for zero downtime upgrades and migrations; and Global Data Services for automated service management and workload balancing in replicated database environments. Each of these technologies requires additional effort to implement. But they deliver substantial value for your most critical applications where downtime and data loss are not an option. The MAA reference architectures are inherently designed to address conflicting realities. On one hand, not every application has the same objectives for availability and data protection – the Not One Size Fits All title of this blog post. On the other hand, standard infrastructure is an operational requirement and a business necessity in order to reduce complexity and cost. MAA reference architectures address both realities by providing a standard infrastructure optimized for Oracle Database that enables you to dial-in the level of HA appropriate for different service level requirements. This makes it simple to move a database from one HA tier to the next should business requirements change, or from one hardware platform to another – whether it’s your favorite non-Oracle vendor or an Oracle Engineered System. Please stay tuned for additional blog posts in this series that dive into the details of each MAA reference architecture. Meanwhile, more information on Oracle HA solutions and the Maximum Availability Architecture can be found at: Oracle Maximum Availability Architecture - Webcast Maximize Availability with Oracle Database 12c - Technical White Paper

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  • ADO and Two Way Storage Tiering

    - by Andy-Oracle
    Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 We get asked the following question about Automatic Data Optimization (ADO) storage tiering quite a bit. Can you tier back to the original location if the data gets hot again? The answer is yes but not with standard Automatic Data Optimization policies, at least not reliably. That's not how ADO is meant to operate. ADO is meant to mirror a traditional view of Information Lifecycle Management (ILM) where data will be very volatile when first created, will become less active or cool, and then will eventually cease to be accessed at all (i.e. cold). I think the reason this question gets asked is because customers realize that many of their business processes are cyclical and the thinking goes that those segments that only get used during month end or year-end cycles could sit on lower cost storage when not being used. Unfortunately this doesn't fit very well with the ADO storage tiering model. ADO storage tiering is based on the amount of free and used space in the source tablespace. There are two parameters that control this behavior, TBS_PERCENT_USED and TBS_PERCENT_FREE. When the space in the tablespace exceeds the TBS_PERCENT_USED value then segments specified in storage tiering clause(s) can be moved until the percent of free space reaches the TBS_PERCENT_FREE value. It is worth mentioning that no checks are made for available space in the target tablespace. Now, it is certainly possible to create custom functions to control storage tiering, but this can get complicated. The biggest problem is insuring that there is enough space to move the segment back to tier 1 storage, assuming that that's the goal. This isn't as much of a problem when moving from tier 1 to tier 2 storage because there is typically more tier 2 storage available. At least that's the premise since it is supposed to be less costly, lower performing and higher capacity storage. In either case though, if there isn't enough space then the operation fails. In the case of a customized function, the question becomes do you attempt to free the space so the move can be made or do you just stop and return false so that the move cannot take place? This is really the crux of the issue. Once you cross into this territory you're really going to have to implement two-way hierarchical storage and the whole point of ADO was to provide automatic storage tiering. You're probably better off using heat map and/or business access requirements and building your own hierarchical storage management infrastructure if you really want two way storage tiering. /* 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:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

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  • Spawn a multi-threaded Java program from a Windows command line program, spawner won't end until spa

    - by Ross Patterson
    Short version: How can I prevent a spawned Java process in Windows from blocking the spawning process from ending? Long version: I'm trying to spawn a multi-threaded Java program (Selenium RC, not that it should matter) from a program launched from the Windows command line (NAnt's <exec> task, again, not that it should matter). I'm doing it using the Windows "start" command, and the spawned process is started and runs correctly. The spawning process receives control back and finishes (NAnt says "BUILD SUCCEEDED"), but doesn't actually exit to the command line. When the spawned process finally terminates (could be hours later), the command process returns and the command line prompt occurs. For example: <target name="start_rc"> <exec program="cmd" failonerror="false" workingdir="${ross.p5.dir}\Tools\selenium\selenium-server-1.0.1" verbose="true"> <arg value="/C"/> <arg value="start"/> <arg value="java"/> <arg value="-jar"/> <arg path="${ross.p5.dir}\Tools\selenium\selenium-server-1.0.1\selenium-server.jar"/> <arg value="-userExtensions"/> <arg path="${ross.p5.dir}\Tools\selenium\selenium-server-1.0.1\user-extensions.js"/> <arg value="-browserSideLog"/> <arg value="-log"/> <arg value="${ross.p5.dir}\artifacts\selenium.log"/> <arg value="-debug"/> </exec> </target> Produces: C :\Ross>nant start_rc NAnt 0.86 (Build 0.86.2898.0; beta1; 12/8/2007) Copyright (C) 2001-2007 Gerry Shaw http://nant.sourceforge.net Buildfile: file:///C:/Ross/ross.build Target framework: Microsoft .NET Framework 3.5 Target(s) specified: start_rc start_rc: [exec] Starting 'cmd (/C start java -jar C:\p5\Tools\selenium\selenium-server-1.0.1\selenium-server.jar -userExtensions C:\p5\Tools\selenium\selenium-server-1.0.1\user-extensions.js -browserSideLog -log C:\p5\artifacts\selenium.log -debug)' in 'C:\p5\Tools\selenium\selenium-server-1.0.1' BUILD SUCCEEDED Total time: 4.1 seconds. ... and then nothing until I close the window where Java is running, then ... C:\Ross> Obviously something is preventing the nant process from terminating, but shouldn't the Windows START command prevent that?

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  • How can I model the data in a multi-language data editor in WPF with MVVM?

    - by Patrick Szalapski
    Are there any good practices to follow when designing a model/ViewModel to represent data in an app that will view/edit that data in multiple languages? Our top-level class--let's call it Course--contains several collection properties, say Books and TopicsCovered, which each might have a collection property among its data. For example, the data needs to represent course1.Books.First().Title in different languages, and course1.TopicsCovered.First().Name in different languages. We want a app that can edit any of the data for one given course in any of the available languages--as well as edit non-language-specific data, perhaps the Author of a Book (i.e. course1.Books.First().Author). We are having trouble figuring out how best to set up the model to enable binding in the XAML view. For example, do we replace (in the single-language model) each String with a collection of LanguageSpecificString instances? So to get the author in the current language: course1.Books.First().Author.Where(Function(a) a.Language = CurrentLanguage).SingleOrDefault If we do that, we cannot easily bind to any value in one given language, only to the collection of language values such as in an ItemsControl. <TextBox Text={Binding Author.???} /> <!-- no way to bind to the current language author --> Do we replace the top-level Course class with a collection of language-specific Courses? So to get the author in the current language: course1.GetLanguage(CurrentLanguage).Books.First.Author If we do that, we can only easily work with one language at a time; we might want a view to show one language and let the user edit the other. <TextBox Text={Binding Author} /> <!-- good --> <TextBlock Text={Binding ??? } /> <!-- no way to bind to the other language author --> Also, that has the disadvantage of not representing language-neutral data as such; every property (such as Author) would seem to be in multiple languages. Even non-string properties would be in multiple languages. Is there an option in between those two? Is there another way that we aren't thinking of? I realize this is somewhat vague, but it would seem to be a somewhat common problem to design for. Note: This is not a question about providing a multilingual UI, but rather about actually editing multi-language data in a flexible way.

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  • Multi-threaded random_r is slower than single threaded version.

    - by Nixuz
    The following program is essentially the same the one described here. When I run and compile the program using two threads (NTHREADS == 2), I get the following run times: real 0m14.120s user 0m25.570s sys 0m0.050s When it is run with just one thread (NTHREADS == 1), I get run times significantly better even though it is only using one core. real 0m4.705s user 0m4.660s sys 0m0.010s My system is dual core, and I know random_r is thread safe and I am pretty sure it is non-blocking. When the same program is run without random_r and a calculation of cosines and sines is used as a replacement, the dual-threaded version runs in about 1/2 the time as expected. #include <pthread.h> #include <stdlib.h> #include <stdio.h> #define NTHREADS 2 #define PRNG_BUFSZ 8 #define ITERATIONS 1000000000 void* thread_run(void* arg) { int r1, i, totalIterations = ITERATIONS / NTHREADS; for (i = 0; i < totalIterations; i++){ random_r((struct random_data*)arg, &r1); } printf("%i\n", r1); } int main(int argc, char** argv) { struct random_data* rand_states = (struct random_data*)calloc(NTHREADS, sizeof(struct random_data)); char* rand_statebufs = (char*)calloc(NTHREADS, PRNG_BUFSZ); pthread_t* thread_ids; int t = 0; thread_ids = (pthread_t*)calloc(NTHREADS, sizeof(pthread_t)); /* create threads */ for (t = 0; t < NTHREADS; t++) { initstate_r(random(), &rand_statebufs[t], PRNG_BUFSZ, &rand_states[t]); pthread_create(&thread_ids[t], NULL, &thread_run, &rand_states[t]); } for (t = 0; t < NTHREADS; t++) { pthread_join(thread_ids[t], NULL); } free(thread_ids); free(rand_states); free(rand_statebufs); } I am confused why when generating random numbers the two threaded version performs much worse than the single threaded version, considering random_r is meant to be used in multi-threaded applications.

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  • What is the best approach in SQL to store multi-level descriptions?

    - by gime
    I need a new perspective on how to design a reliable and efficient SQL database to store multi-level arrays of data. This problem applies to many situations but I came up with this example: There are hundreds of products. Each product has an undefined number of parts. Each part is built from several elements. All products are described in the same way. All parts would require the same fields to describe them (let's say: price, weight, part name), all elements of all parts also have uniform design (for example: element code, manufacturer). Plain and simple. One element may be related to only part, and each part is related to one product only. I came up with idea of three tables: Products: -------------------------------------------- prod_id prod_name prod_price prod_desc 1 hoover 120 unused next Parts: ---------------------------------------------------- part_id part_name part_price part_weight prod_id 3 engine 10 20 1 and finally Elements: --------------------------------------- el_id el_code el_manufacturer part_id 1 BFG12 GE 3 Now, select a desired product, select all from PARTS where prod_id is the same, and then select all from ELEMENTS where part_id matches - after multiple queries you've got all data. I'm just not sure if this is the right approach. I've got also another idea, without ELEMENTS table. That would decrease queries but I'm a bit afraid it might be lame and bad practice. Instead of ELEMENTS table there are two more fields in the PARTS table, so it looks like this: part_id, part_name, part_price, part_weight, prod_id, part_el_code, part_el_manufacturer they would be text type, and for each part, information about elements would be stored as strings, this way: part_el_code | code_of_element1; code_of_element2; code_of_element3 part_el_manufacturer | manuf_of_element1; manuf_of_element2; manuf_of_element3 Then all we need is to explode() data from those fields, and we get arrays, easy to display. Of course this is not perfect and has some limitations, but is this idea ok? Or should I just go with the first idea? Or maybe there is a better approach to this problem? It's really hard to describe it in few words, and that means it's hard to search for answer. Also, understanding the principles of designing databases is not that easy as it seems.

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  • C#/.NET Little Wonders: The Concurrent Collections (1 of 3)

    - by James Michael Hare
    Once again we consider some of the lesser known classes and keywords of C#.  In the next few weeks, we will discuss the concurrent collections and how they have changed the face of concurrent programming. This week’s post will begin with a general introduction and discuss the ConcurrentStack<T> and ConcurrentQueue<T>.  Then in the following post we’ll discuss the ConcurrentDictionary<T> and ConcurrentBag<T>.  Finally, we shall close on the third post with a discussion of the BlockingCollection<T>. For more of the "Little Wonders" posts, see the index here. A brief history of collections In the beginning was the .NET 1.0 Framework.  And out of this framework emerged the System.Collections namespace, and it was good.  It contained all the basic things a growing programming language needs like the ArrayList and Hashtable collections.  The main problem, of course, with these original collections is that they held items of type object which means you had to be disciplined enough to use them correctly or you could end up with runtime errors if you got an object of a type you weren't expecting. Then came .NET 2.0 and generics and our world changed forever!  With generics the C# language finally got an equivalent of the very powerful C++ templates.  As such, the System.Collections.Generic was born and we got type-safe versions of all are favorite collections.  The List<T> succeeded the ArrayList and the Dictionary<TKey,TValue> succeeded the Hashtable and so on.  The new versions of the library were not only safer because they checked types at compile-time, in many cases they were more performant as well.  So much so that it's Microsoft's recommendation that the System.Collections original collections only be used for backwards compatibility. So we as developers came to know and love the generic collections and took them into our hearts and embraced them.  The problem is, thread safety in both the original collections and the generic collections can be problematic, for very different reasons. Now, if you are only doing single-threaded development you may not care – after all, no locking is required.  Even if you do have multiple threads, if a collection is “load-once, read-many” you don’t need to do anything to protect that container from multi-threaded access, as illustrated below: 1: public static class OrderTypeTranslator 2: { 3: // because this dictionary is loaded once before it is ever accessed, we don't need to synchronize 4: // multi-threaded read access 5: private static readonly Dictionary<string, char> _translator = new Dictionary<string, char> 6: { 7: {"New", 'N'}, 8: {"Update", 'U'}, 9: {"Cancel", 'X'} 10: }; 11:  12: // the only public interface into the dictionary is for reading, so inherently thread-safe 13: public static char? Translate(string orderType) 14: { 15: char charValue; 16: if (_translator.TryGetValue(orderType, out charValue)) 17: { 18: return charValue; 19: } 20:  21: return null; 22: } 23: } Unfortunately, most of our computer science problems cannot get by with just single-threaded applications or with multi-threading in a load-once manner.  Looking at  today's trends, it's clear to see that computers are not so much getting faster because of faster processor speeds -- we've nearly reached the limits we can push through with today's technologies -- but more because we're adding more cores to the boxes.  With this new hardware paradigm, it is even more important to use multi-threaded applications to take full advantage of parallel processing to achieve higher application speeds. So let's look at how to use collections in a thread-safe manner. Using historical collections in a concurrent fashion The early .NET collections (System.Collections) had a Synchronized() static method that could be used to wrap the early collections to make them completely thread-safe.  This paradigm was dropped in the generic collections (System.Collections.Generic) because having a synchronized wrapper resulted in atomic locks for all operations, which could prove overkill in many multithreading situations.  Thus the paradigm shifted to having the user of the collection specify their own locking, usually with an external object: 1: public class OrderAggregator 2: { 3: private static readonly Dictionary<string, List<Order>> _orders = new Dictionary<string, List<Order>>(); 4: private static readonly _orderLock = new object(); 5:  6: public void Add(string accountNumber, Order newOrder) 7: { 8: List<Order> ordersForAccount; 9:  10: // a complex operation like this should all be protected 11: lock (_orderLock) 12: { 13: if (!_orders.TryGetValue(accountNumber, out ordersForAccount)) 14: { 15: _orders.Add(accountNumber, ordersForAccount = new List<Order>()); 16: } 17:  18: ordersForAccount.Add(newOrder); 19: } 20: } 21: } Notice how we’re performing several operations on the dictionary under one lock.  With the Synchronized() static methods of the early collections, you wouldn’t be able to specify this level of locking (a more macro-level).  So in the generic collections, it was decided that if a user needed synchronization, they could implement their own locking scheme instead so that they could provide synchronization as needed. The need for better concurrent access to collections Here’s the problem: it’s relatively easy to write a collection that locks itself down completely for access, but anything more complex than that can be difficult and error-prone to write, and much less to make it perform efficiently!  For example, what if you have a Dictionary that has frequent reads but in-frequent updates?  Do you want to lock down the entire Dictionary for every access?  This would be overkill and would prevent concurrent reads.  In such cases you could use something like a ReaderWriterLockSlim which allows for multiple readers in a lock, and then once a writer grabs the lock it blocks all further readers until the writer is done (in a nutshell).  This is all very complex stuff to consider. Fortunately, this is where the Concurrent Collections come in.  The Parallel Computing Platform team at Microsoft went through great pains to determine how to make a set of concurrent collections that would have the best performance characteristics for general case multi-threaded use. Now, as in all things involving threading, you should always make sure you evaluate all your container options based on the particular usage scenario and the degree of parallelism you wish to acheive. This article should not be taken to understand that these collections are always supperior to the generic collections. Each fills a particular need for a particular situation. Understanding what each container is optimized for is key to the success of your application whether it be single-threaded or multi-threaded. General points to consider with the concurrent collections The MSDN points out that the concurrent collections all support the ICollection interface. However, since the collections are already synchronized, the IsSynchronized property always returns false, and SyncRoot always returns null.  Thus you should not attempt to use these properties for synchronization purposes. Note that since the concurrent collections also may have different operations than the traditional data structures you may be used to.  Now you may ask why they did this, but it was done out of necessity to keep operations safe and atomic.  For example, in order to do a Pop() on a stack you have to know the stack is non-empty, but between the time you check the stack’s IsEmpty property and then do the Pop() another thread may have come in and made the stack empty!  This is why some of the traditional operations have been changed to make them safe for concurrent use. In addition, some properties and methods in the concurrent collections achieve concurrency by creating a snapshot of the collection, which means that some operations that were traditionally O(1) may now be O(n) in the concurrent models.  I’ll try to point these out as we talk about each collection so you can be aware of any potential performance impacts.  Finally, all the concurrent containers are safe for enumeration even while being modified, but some of the containers support this in different ways (snapshot vs. dirty iteration).  Once again I’ll highlight how thread-safe enumeration works for each collection. ConcurrentStack<T>: The thread-safe LIFO container The ConcurrentStack<T> is the thread-safe counterpart to the System.Collections.Generic.Stack<T>, which as you may remember is your standard last-in-first-out container.  If you think of algorithms that favor stack usage (for example, depth-first searches of graphs and trees) then you can see how using a thread-safe stack would be of benefit. The ConcurrentStack<T> achieves thread-safe access by using System.Threading.Interlocked operations.  This means that the multi-threaded access to the stack requires no traditional locking and is very, very fast! For the most part, the ConcurrentStack<T> behaves like it’s Stack<T> counterpart with a few differences: Pop() was removed in favor of TryPop() Returns true if an item existed and was popped and false if empty. PushRange() and TryPopRange() were added Allows you to push multiple items and pop multiple items atomically. Count takes a snapshot of the stack and then counts the items. This means it is a O(n) operation, if you just want to check for an empty stack, call IsEmpty instead which is O(1). ToArray() and GetEnumerator() both also take snapshots. This means that iteration over a stack will give you a static view at the time of the call and will not reflect updates. Pushing on a ConcurrentStack<T> works just like you’d expect except for the aforementioned PushRange() method that was added to allow you to push a range of items concurrently. 1: var stack = new ConcurrentStack<string>(); 2:  3: // adding to stack is much the same as before 4: stack.Push("First"); 5:  6: // but you can also push multiple items in one atomic operation (no interleaves) 7: stack.PushRange(new [] { "Second", "Third", "Fourth" }); For looking at the top item of the stack (without removing it) the Peek() method has been removed in favor of a TryPeek().  This is because in order to do a peek the stack must be non-empty, but between the time you check for empty and the time you execute the peek the stack contents may have changed.  Thus the TryPeek() was created to be an atomic check for empty, and then peek if not empty: 1: // to look at top item of stack without removing it, can use TryPeek. 2: // Note that there is no Peek(), this is because you need to check for empty first. TryPeek does. 3: string item; 4: if (stack.TryPeek(out item)) 5: { 6: Console.WriteLine("Top item was " + item); 7: } 8: else 9: { 10: Console.WriteLine("Stack was empty."); 11: } Finally, to remove items from the stack, we have the TryPop() for single, and TryPopRange() for multiple items.  Just like the TryPeek(), these operations replace Pop() since we need to ensure atomically that the stack is non-empty before we pop from it: 1: // to remove items, use TryPop or TryPopRange to get multiple items atomically (no interleaves) 2: if (stack.TryPop(out item)) 3: { 4: Console.WriteLine("Popped " + item); 5: } 6:  7: // TryPopRange will only pop up to the number of spaces in the array, the actual number popped is returned. 8: var poppedItems = new string[2]; 9: int numPopped = stack.TryPopRange(poppedItems); 10:  11: foreach (var theItem in poppedItems.Take(numPopped)) 12: { 13: Console.WriteLine("Popped " + theItem); 14: } Finally, note that as stated before, GetEnumerator() and ToArray() gets a snapshot of the data at the time of the call.  That means if you are enumerating the stack you will get a snapshot of the stack at the time of the call.  This is illustrated below: 1: var stack = new ConcurrentStack<string>(); 2:  3: // adding to stack is much the same as before 4: stack.Push("First"); 5:  6: var results = stack.GetEnumerator(); 7:  8: // but you can also push multiple items in one atomic operation (no interleaves) 9: stack.PushRange(new [] { "Second", "Third", "Fourth" }); 10:  11: while(results.MoveNext()) 12: { 13: Console.WriteLine("Stack only has: " + results.Current); 14: } The only item that will be printed out in the above code is "First" because the snapshot was taken before the other items were added. This may sound like an issue, but it’s really for safety and is more correct.  You don’t want to enumerate a stack and have half a view of the stack before an update and half a view of the stack after an update, after all.  In addition, note that this is still thread-safe, whereas iterating through a non-concurrent collection while updating it in the old collections would cause an exception. ConcurrentQueue<T>: The thread-safe FIFO container The ConcurrentQueue<T> is the thread-safe counterpart of the System.Collections.Generic.Queue<T> class.  The concurrent queue uses an underlying list of small arrays and lock-free System.Threading.Interlocked operations on the head and tail arrays.  Once again, this allows us to do thread-safe operations without the need for heavy locks! The ConcurrentQueue<T> (like the ConcurrentStack<T>) has some departures from the non-concurrent counterpart.  Most notably: Dequeue() was removed in favor of TryDequeue(). Returns true if an item existed and was dequeued and false if empty. Count does not take a snapshot It subtracts the head and tail index to get the count.  This results overall in a O(1) complexity which is quite good.  It’s still recommended, however, that for empty checks you call IsEmpty instead of comparing Count to zero. ToArray() and GetEnumerator() both take snapshots. This means that iteration over a queue will give you a static view at the time of the call and will not reflect updates. The Enqueue() method on the ConcurrentQueue<T> works much the same as the generic Queue<T>: 1: var queue = new ConcurrentQueue<string>(); 2:  3: // adding to queue is much the same as before 4: queue.Enqueue("First"); 5: queue.Enqueue("Second"); 6: queue.Enqueue("Third"); For front item access, the TryPeek() method must be used to attempt to see the first item if the queue.  There is no Peek() method since, as you’ll remember, we can only peek on a non-empty queue, so we must have an atomic TryPeek() that checks for empty and then returns the first item if the queue is non-empty. 1: // to look at first item in queue without removing it, can use TryPeek. 2: // Note that there is no Peek(), this is because you need to check for empty first. TryPeek does. 3: string item; 4: if (queue.TryPeek(out item)) 5: { 6: Console.WriteLine("First item was " + item); 7: } 8: else 9: { 10: Console.WriteLine("Queue was empty."); 11: } Then, to remove items you use TryDequeue().  Once again this is for the same reason we have TryPeek() and not Peek(): 1: // to remove items, use TryDequeue. If queue is empty returns false. 2: if (queue.TryDequeue(out item)) 3: { 4: Console.WriteLine("Dequeued first item " + item); 5: } Just like the concurrent stack, the ConcurrentQueue<T> takes a snapshot when you call ToArray() or GetEnumerator() which means that subsequent updates to the queue will not be seen when you iterate over the results.  Thus once again the code below will only show the first item, since the other items were added after the snapshot. 1: var queue = new ConcurrentQueue<string>(); 2:  3: // adding to queue is much the same as before 4: queue.Enqueue("First"); 5:  6: var iterator = queue.GetEnumerator(); 7:  8: queue.Enqueue("Second"); 9: queue.Enqueue("Third"); 10:  11: // only shows First 12: while (iterator.MoveNext()) 13: { 14: Console.WriteLine("Dequeued item " + iterator.Current); 15: } Using collections concurrently You’ll notice in the examples above I stuck to using single-threaded examples so as to make them deterministic and the results obvious.  Of course, if we used these collections in a truly multi-threaded way the results would be less deterministic, but would still be thread-safe and with no locking on your part required! For example, say you have an order processor that takes an IEnumerable<Order> and handles each other in a multi-threaded fashion, then groups the responses together in a concurrent collection for aggregation.  This can be done easily with the TPL’s Parallel.ForEach(): 1: public static IEnumerable<OrderResult> ProcessOrders(IEnumerable<Order> orderList) 2: { 3: var proxy = new OrderProxy(); 4: var results = new ConcurrentQueue<OrderResult>(); 5:  6: // notice that we can process all these in parallel and put the results 7: // into our concurrent collection without needing any external locking! 8: Parallel.ForEach(orderList, 9: order => 10: { 11: var result = proxy.PlaceOrder(order); 12:  13: results.Enqueue(result); 14: }); 15:  16: return results; 17: } Summary Obviously, if you do not need multi-threaded safety, you don’t need to use these collections, but when you do need multi-threaded collections these are just the ticket! The plethora of features (I always think of the movie The Three Amigos when I say plethora) built into these containers and the amazing way they acheive thread-safe access in an efficient manner is wonderful to behold. Stay tuned next week where we’ll continue our discussion with the ConcurrentBag<T> and the ConcurrentDictionary<TKey,TValue>. For some excellent information on the performance of the concurrent collections and how they perform compared to a traditional brute-force locking strategy, see this wonderful whitepaper by the Microsoft Parallel Computing Platform team here.   Tweet Technorati Tags: C#,.NET,Concurrent Collections,Collections,Multi-Threading,Little Wonders,BlackRabbitCoder,James Michael Hare

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  • Configure PERL DBI and DBD in Linux

    - by Balualways
    I am new to Perl and I work in a Linux OEL 5x server. I am trying to configure the Perl DB modules for Oracle connectivity (DBD and DBI modules). Can anyone help me out in the installation procedure? I had tried CPAN didn't really worked out. Any help would be appreciated. I am not quite sure I need to initialize any variables other than $LD_LIBRARY_PATH and $ORACLE_HOME These are my observations: ISSUE:: I am getting the following issue while using the DBI module to connect to Oracle: install_driver(Oracle) failed: Can't locate loadable object for module DBD::Oracle in @INC (@INC contains: /usr/lib64/perl5/site_perl/5.8.8/x86_64-linux-thread-multi /usr/lib/perl5/site_perl/5.8.8 /usr/lib/perl5/site_perl /usr/lib64/perl5/vendor_perl/5.8.8/x86_64-linux-thread-multi /usr/lib/perl5/vendor_perl/5.8.8 /usr/lib/perl5/vendor_perl /usr/lib64/perl5/5.8.8/x86_64-linux-thread-multi /usr/lib/perl5/5.8.8 .) at (eval 3) line 3 Compilation failed in require at (eval 3) line 3. Perhaps a module that DBD::Oracle requires hasn't been fully installed at connectdb.pl line 57 I had installed the DBD for oracle from /usr/lib64/perl5/5.8.8/x86_64-linux-thread-multi/DBD/DBD-Oracle-1.50 Could you please take a look into the steps and correct me if I am wrong: Observations: $ echo $LD_LIBRARY_PATH /opt/CA/UnicenterAutoSysJM/autosys/lib:/opt/CA/SharedComponents/Csam/SockAdapter/lib:/opt/CA/SharedComponents/ETPKI/lib:/opt/CA/CAlib $ echo $ORACLE_HOME /usr/local/oracle/ORA This is how I tried to install the DBD module: Download the file DBD 1.50 for Oracle Copy to /usr/lib64/perl5/5.8.8/x86_64-linux-thread-multi/DBD Untar and Makefile.PL . Message: Using DBI 1.52 (for perl 5.008008 on x86_64-linux-thread-multi) installed in /usr/lib64/perl5/vendor_perl/5.8.8/x86_64-linux-thread-multi/auto/DBI/ Configuring DBD::Oracle for perl 5.008008 on linux (x86_64-linux-thread-multi) Remember to actually *READ* the README file! Especially if you have any problems. Installing on a linux, Ver#2.6 Using Oracle in /opt/oracle/product/10.2 DEFINE _SQLPLUS_RELEASE = "1002000400" (CHAR) Oracle version 10.2.0.4 (10.2) Found /opt/oracle/product/10.2/rdbms/demo/demo_rdbms.mk Found /opt/oracle/product/10.2/rdbms/demo/demo_rdbms64.mk Found /opt/oracle/product/10.2/rdbms/lib/ins_rdbms.mk Using /opt/oracle/product/10.2/rdbms/demo/demo_rdbms.mk Your LD_LIBRARY_PATH env var is set to '/usr/local/oracle/ORA/lib:/usr/dt/lib:/usr/openwin/lib:/usr/local/oracle/ORA/ows/cartx/wodbc/1.0/util/lib:/usr/local/oracle/ORA/lib:/usr/local/sybase/OCS-12_0/lib:/usr/local/sybase/lib:/home/oracle/jdbc/jdbcoci73/lib:./' WARNING: Your LD_LIBRARY_PATH env var doesn't include '/opt/oracle/product/10.2/lib' but probably needs to. Reading /opt/oracle/product/10.2/rdbms/demo/demo_rdbms.mk Reading /usr/local/oracle/ORA/rdbms/lib/env_rdbms.mk Attempting to discover Oracle OCI build rules sh: make: command not found by executing: [make -f /opt/oracle/product/10.2/rdbms/demo/demo_rdbms.mk build ECHODO=echo ECHO=echo GENCLNTSH='echo genclntsh' CC=true OPTIMIZE= CCFLAGS= EXE=DBD_ORA_EXE OBJS=DBD_ORA_OBJ.o] WARNING: Oracle build rule discovery failed (32512) Add path to make command into your PATH environment variable. Oracle oci build prolog: [sh: make: command not found] Oracle oci build command: [] WARNING: Unable to interpret Oracle build commands from /opt/oracle/product/10.2/rdbms/demo/demo_rdbms.mk. (Will continue by using fallback approach.) Please report this to [email protected]. See README for what to include. Found header files in /opt/oracle/product/10.2/rdbms/public. client_version=10.2 DEFINE= -Wall -Wno-comment -DUTF8_SUPPORT -DORA_OCI_VERSION=\"10.2.0.4\" -DORA_OCI_102 Checking for functioning wait.ph System: perl5.008008 linux ca-build9.us.oracle.com 2.6.20-1.3002.fc6xen #1 smp thu apr 30 18:08:39 pdt 2009 x86_64 x86_64 x86_64 gnulinux Compiler: gcc -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic -D_REENTRANT -D_GNU_SOURCE -fno-strict-aliasing -pipe -Wdeclaration-after-statement -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -I/usr/include/gdbm Linker: not found Sysliblist: -ldl -lm -lpthread -lnsl -lirc Oracle makefiles would have used these definitions but we override them: CC: cc CFLAGS: $(GFLAG) $(OPTIMIZE) $(CDEBUG) $(CCFLAGS) $(PFLAGS)\ $(SHARED_CFLAG) $(USRFLAGS) [$(GFLAG) -O3 $(CDEBUG) -m32 $(TRIGRAPHS_CCFLAGS) -fPIC -I/usr/local/oracle/ORA/rdbms/demo -I/usr/local/oracle/ORA/rdbms/public -I/usr/local/oracle/ORA/plsql/public -I/usr/local/oracle/ORA/network/public -DLINUX -D_GNU_SOURCE -D_LARGEFILE64_SOURCE=1 -D_LARGEFILE_SOURCE=1 -DSLTS_ENABLE -DSLMXMX_ENABLE -D_REENTRANT -DNS_THREADS -fno-strict-aliasing $(LPFLAGS) $(USRFLAGS)] build: $(CC) $(ORALIBPATH) -o $(EXE) $(OBJS) $(OCISHAREDLIBS) [ cc -L$(LIBHOME) -L/usr/local/oracle/ORA/rdbms/lib/ -o $(EXE) $(OBJS) -lclntsh $(EXPDLIBS) $(EXOSLIBS) -ldl -lm -lpthread -lnsl -lirc -ldl -lm $(USRLIBS) -lpthread] LDFLAGS: $(LDFLAGS32) [-m32 -o $@ -L/usr/local/oracle/ORA/rdbms//lib32/ -L/usr/local/oracle/ORA/lib32/ -L/usr/local/oracle/ORA/lib32/stubs/] Linking with /usr/local/oracle/ORA/rdbms/lib/defopt.o -lclntsh -ldl -lm -lpthread -lnsl -lirc -ldl -lm -lpthread [from $(DEF_OPT) $(OCISHAREDLIBS)] Checking if your kit is complete... Looks good LD_RUN_PATH=/usr/local/oracle/ORA/lib Using DBD::Oracle 1.50. Using DBD::Oracle 1.50. Using DBI 1.52 (for perl 5.008008 on x86_64-linux-thread-multi) installed in /usr/lib64/perl5/vendor_perl/5.8.8/x86_64-linux-thread-multi/auto/DBI/ Writing Makefile for DBD::Oracle Writing MYMETA.yml and MYMETA.json *** If you have problems... read all the log printed above, and the README and README.help.txt files. (Of course, you have read README by now anyway, haven't you?)

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  • Reading email address from contacts fails with weird memory issue - Solved

    - by CapsicumDreams
    Hi all, I'm stumped. I'm trying to get a list of all the email address a person has. I'm using the ABPeoplePickerNavigationController to select the person, which all seems fine. I'm setting my ABRecordRef personDealingWith; from the person argument to - (BOOL)peoplePickerNavigationController:(ABPeoplePickerNavigationController *)peoplePicker shouldContinueAfterSelectingPerson:(ABRecordRef)person property:(ABPropertyID)property identifier:(ABMultiValueIdentifier)identifier { and everything seems fine up till this point. The first time the following code executes, all is well. When subsequently run, I can get issues. First, the code: // following line seems to make the difference (issue 1) // NSLog(@"%d", ABMultiValueGetCount(ABRecordCopyValue(personDealingWith, kABPersonEmailProperty))); // construct array of emails ABMultiValueRef multi = ABRecordCopyValue(personDealingWith, kABPersonEmailProperty); CFIndex emailCount = ABMultiValueGetCount(multi); if (emailCount > 0) { // collect all emails in array for (CFIndex i = 0; i < emailCount; i++) { CFStringRef emailRef = ABMultiValueCopyValueAtIndex(multi, i); [emailArray addObject:(NSString *)emailRef]; CFRelease(emailRef); } } // following line also matters (issue 2) CFRelease(multi); If compiled as written, the are no errors or static analysis problems. This crashes with a *** -[Not A Type retain]: message sent to deallocated instance 0x4e9dc60 error. But wait, there's more! I can fix it in either of two ways. Firstly, I can uncomment the NSLog at the top of the function. I get a leak from the NSLog's ABRecordCopyValue every time through, but the code seems to run fine. Also, I can comment out the CFRelease(multi); at the end, which does exactly the same thing. Static compilation errors, but running code. So without a leak, this function crashes. To prevent a crash, I need to haemorrhage memory. Neither is a great solution. Can anyone point out what's going on? Solution: It turned out that I wasn't storing the ABRecordRef personDealingWith var correctly. I'm still not sure how to do that properly, but instead of having the functionality in another routine (performed later), I'm now doing the grunt-work in the delegate method, and using the derived results at my leisure. The new (working) routine: - (BOOL)peoplePickerNavigationController:(ABPeoplePickerNavigationController *)peoplePicker shouldContinueAfterSelectingPerson:(ABRecordRef)person { // as soon as they select someone, return personDealingWithFullName = (NSString *)ABRecordCopyCompositeName(person); personDealingWithFirstName = (NSString *)ABRecordCopyValue(person, kABPersonFirstNameProperty); // construct array of emails [personDealingWithEmails removeAllObjects]; ABMutableMultiValueRef multi = ABRecordCopyValue(person, kABPersonEmailProperty); if (ABMultiValueGetCount(multi) > 0) { // collect all emails in array for (CFIndex i = 0; i < ABMultiValueGetCount(multi); i++) { CFStringRef emailRef = ABMultiValueCopyValueAtIndex(multi, i); [personDealingWithEmails addObject:(NSString *)emailRef]; CFRelease(emailRef); } } CFRelease(multi); return NO; }

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  • What is the best project setup in this situation?

    - by Tong Wang
    The presentation tier will contain 2 web modules (serving different purposes and based on different technologies), the middle tier will be Spring beans without EJBs and the persistence tier will be JPA on Hibernate. I am wondering what would be the best project setup in this case. The IDE I am planning to use is MyEclipse 8.5. Thanks.

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  • Java JRE 1.7.0_60 Certified with Oracle E-Business Suite

    - by Steven Chan (Oracle Development)
    Java Runtime Environment 7u60 (a.k.a. JRE 7u60-b19) and later updates on the JRE 7 codeline are now certified with Oracle E-Business Suite Release 11i and 12.0, 12.1, and 12.2 for Windows-based desktop clients. Effects of new support dates on Java upgrades for EBS environments Support dates for the E-Business Suite and Java have changed.  Please review the sections below for more details: What does this mean for Oracle E-Business Suite users? Will EBS users be forced to upgrade to JRE 7 for Windows desktop clients? Will EBS users be forced to upgrade to JDK 7 for EBS application tier servers? All JRE 6 and 7 releases are certified with EBS upon release Our standard policy is that all E-Business Suite customers can apply all JRE updates to end-user desktops from JRE 1.6.0_03 and later updates on the 1.6 codeline, and from JRE 7u10 and later updates on the JRE 7 codeline.  We test all new JRE 1.6 and JRE 7 releases in parallel with the JRE development process, so all new JRE 1.6 and 7 releases are considered certified with the E-Business Suite on the same day that they're released by our Java team.  You do not need to wait for a certification announcement before applying new JRE 1.6 or JRE 7 releases to your EBS users' desktops. What's new in JRE 1.7.0_60? JDK 7u60 contains IANA time zone data version 2014b. For more information, refer to Timezone Data Versions in the JRE Software. It is strongly recommended that all customers upgrade to this release.  Details about update in this release are listed in the release notes. 32-bit and 64-bit versions certified This certification includes both the 32-bit and 64-bit JRE versions for various Windows operating systems. See the respective Recommended Browser documentation for your EBS release for details. Where are the official patch requirements documented? All patches required for ensuring full compatibility of the E-Business Suite with JRE 7 are documented in these Notes: For EBS 11i: Deploying Sun JRE (Native Plug-in) for Windows Clients in Oracle E-Business Suite Release 11i (Note 290807.1) Upgrading Developer 6i with Oracle E-Business Suite 11i (Note 125767.1) For EBS 12.0, 12.1, 12.2 Deploying Sun JRE (Native Plug-in) for Windows Clients in Oracle E-Business Suite Release 12 (Note 393931.1) Upgrading OracleAS 10g Forms and Reports in Oracle E-Business Suite Release 12 (Note 437878.1) EBS + Discoverer 11g Users JRE 1.7.0_60 is certified for Discoverer 11g in E-Business Suite environments with the following minimum requirements: Discoverer (11g) 11.1.1.6 plus Patch 13877486 and later  Reference: How To Find Oracle BI Discoverer 10g and 11g Certification Information (Document 233047.1) Worried about the 'mismanaged session cookie' issue? No need to worry -- it's fixed.  To recap: JRE releases 1.6.0_18 through 1.6.0_22 had issues with mismanaging session cookies that affected some users in some circumstances. The fix for those issues was first included in JRE 1.6.0_23. These fixes will carry forward and continue to be fixed in all future JRE releases on the JRE 6 and 7 codelines.  In other words, if you wish to avoid the mismanaged session cookie issue, you should apply any release after JRE 1.6.0_22 on the JRE 6 codeline, and JRE 7u10 and later JRE 7 codeline updates. Implications of Java 6 End of Public Updates for EBS Users The Support Roadmap for Oracle Java is published here: Oracle Java SE Support Roadmap The latest updates to that page (as of Sept. 19, 2012) state (emphasis added): Java SE 6 End of Public Updates Notice After February 2013, Oracle will no longer post updates of Java SE 6 to its public download sites. Existing Java SE 6 downloads already posted as of February 2013 will remain accessible in the Java Archive on Oracle Technology Network. Developers and end-users are encouraged to update to more recent Java SE versions that remain available for public download. For enterprise customers, who need continued access to critical bug fixes and security fixes as well as general maintenance for Java SE 6 or older versions, long term support is available through Oracle Java SE Support . What does this mean for Oracle E-Business Suite users? EBS users fall under the category of "enterprise users" above.  Java is an integral part of the Oracle E-Business Suite technology stack, so EBS users will continue to receive Java SE 6 updates from February 2013 to the end of Java SE 6 Extended Support in June 2017. In other words, nothing changes for EBS users after February 2013.  EBS users will continue to receive critical bug fixes and security fixes as well as general maintenance for Java SE 6 until the end of Java SE 6 Extended Support in June 2017. How can EBS customers obtain Java 6 updates after the public end-of-life? EBS customers can download Java 6 patches from My Oracle Support.  For a complete list of all Java SE patch numbers, see: All Java SE Downloads on MOS (Note 1439822.1) Both JDK and JRE packages are contained in a single combined download after 6u45.  Download the "JDK" package for both the desktop client JRE and the server-side JDK package.  Will EBS users be forced to upgrade to JRE 7 for Windows desktop clients? This upgrade is highly recommended but remains optional while Java 6 is covered by Extended Support. Updates will be delivered via My Oracle Support, where you can continue to receive critical bug fixes and security fixes as well as general maintenance for JRE 6 desktop clients.  Java 6 is covered by Extended Support until June 2017.  All E-Business Suite customers must upgrade to JRE 7 by June 2017. Coexistence of JRE 6 and JRE 7 on Windows desktops The upgrade to JRE 7 is highly recommended for EBS users, but some users may need to run both JRE 6 and 7 on their Windows desktops for reasons unrelated to the E-Business Suite. Most EBS configurations with IE and Firefox use non-static versioning by default. JRE 7 will be invoked instead of JRE 6 if both are installed on a Windows desktop. For more details, see "Appendix B: Static vs. Non-static Versioning and Set Up Options" in Notes 290807.1 and 393931.1. Applying Updates to JRE 6 and JRE 7 to Windows desktops Auto-update will keep JRE 7 up-to-date for Windows users with JRE 7 installed. Auto-update will only keep JRE 7 up-to-date for Windows users with both JRE 6 and 7 installed.  JRE 6 users are strongly encouraged to apply the latest Critical Patch Updates as soon as possible after each release. The Jave SE CPUs will be available via My Oracle Support.  EBS users can find more information about JRE 6 and 7 updates here: Information Center: Installation & Configuration for Oracle Java SE (Note 1412103.2) The dates for future Java SE CPUs can be found on the Critical Patch Updates, Security Alerts and Third Party Bulletin.  An RSS feed is available on that site for those who would like to be kept up-to-date. What do Mac users need? Mac users running Mac OS X 10.9 can run JRE 7 plug-ins.  See this article: EBS Release 12 Certified with Mac OS X 10.9 with Safari 7 and JRE 7 Will EBS users be forced to upgrade to JDK 7 for EBS application tier servers? JRE is used for desktop clients.  JDK is used for application tier servers JDK upgrades for E-Business Suite application tier servers are highly recommended but currently remain optional while Java 6 is covered by Extended Support. Updates will be delivered via My Oracle Support, where you can continue to receive critical bug fixes and security fixes as well as general maintenance for JDK 6 for application tier servers.  Java SE 6 is covered by Extended Support until June 2017.  All EBS customers with application tier servers on Windows, Solaris, and Linux must upgrade to JDK 7 by June 2017. EBS customers running their application tier servers on other operating systems should check with their respective vendors for the support dates for those platforms. JDK 7 is certified with E-Business Suite 12.  See: Java (JDK) 7 Certified for E-Business Suite 12.0 and 12.1 Servers Java (JDK) 7 Certified with E-Business Suite 12.2 Servers References Recommended Browsers for Oracle Applications 11i (Metalink Note 285218.1) Upgrading Sun JRE (Native Plug-in) with Oracle Applications 11i for Windows Clients (Metalink Note 290807.1) Recommended Browsers for Oracle Applications 12 (MetaLink Note 389422.1) Upgrading JRE Plugin with Oracle Applications R12 (MetaLink Note 393931.1) Related Articles Mismanaged Session Cookie Issue Fixed for EBS in JRE 1.6.0_23 Roundup: Oracle JInitiator 1.3 Desupported for EBS Customers in July 2009

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  • Parallelism implies concurrency but not the other way round right?

    - by Cedric Martin
    I often read that parallelism and concurrency are different things. Very often the answerers/commenters go as far as writing that they're two entirely different things. Yet in my view they're related but I'd like some clarification on that. For example if I'm on a multi-core CPU and manage to divide the computation into x smaller computation (say using fork/join) each running in its own thread, I'll have a program that is both doing parallel computation (because supposedly at any point in time several threads are going to run on several cores) and being concurrent right? While if I'm simply using, say, Java and dealing with UI events and repaints on the Event Dispatch Thread plus running the only thread I created myself, I'll have a program that is concurrent (EDT + GC thread + my main thread etc.) but not parallel. I'd like to know if I'm getting this right and if parallelism (on a "single but multi-cores" system) always implies concurrency or not? Also, are multi-threaded programs running on multi-cores CPU but where the different threads are doing totally different computation considered to be using "parallelism"?

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  • zabbix monitoring mysql database

    - by krisdigitx
    I have a server running multiple instances of mysql and also has the zabbix-agent running. In zabbix_agentd.conf i have specified: UserParameter=multi.mysql[*],mysqladmin --socket=$1 -uzabbixagent extended-status 2>/dev/null | awk '/ $3 /{print $$4}' where $1 is the socket instance. From the zabbix server i can run the test successfully. zabbix_get -s ip_of_server -k multi.mysql[/var/lib/mysql/mysql2.sock] and it returns all the values However the zabbix item/trigger does not generate the graphs, I have created a MACRO for $1 which is the socket location {$MYSQL_SOCKET1} = '/var/lib/mysql/mysql2.sock' and i use this key in items to poll the value multi.mysql[{$MYSQL_SOCKET1},Bytes_sent] LOGS: this is what i get on the logs: 3360:20120214:144716.278 item [multi.mysql['/var/lib/mysql/mysql2.sock',Bytes_received]] error: Special characters '\'"`*?[]{}~$!&;()<>|#@' are not allowed in the parameters 3360:20120214:144716.372 item [multi.mysql['/var/lib/mysql/mysql2.sock',Bytes_sent]] error: Special characters '\'"`*?[]{}~$!&;()<>|#@' are not allowed in the parameters Any ideas where the problem could be? FIXED {$MYSQL_SOCKET1} = /var/lib/mysql/mysql2.sock i removed the single quotes from the line and it worked...

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  • Would anybody mind taking a look at my XML structure?

    - by Bill H
    I am relatively new to this but I was hoping somebody could offer up a good critique of this XML structure I put together. I am not looking for anything in depth but rather if somebody notices anything inherently wrong with the structure (or any tips to make it better) I'd greatly appreciate it. We have a large amount of products that we wholesale out and our customers were looking for a data feed to incorporate our products into their websites. <product modified=""> <id></id> <title></title> <description></description> <upc></upc> <quantity></quantity> <images> <image width="" height=""></image> <image width="" height=""></image> <image width="" height=""></image> </images> <category> <name></name> <subcategory></subcategory> </category> <sale expiration="">yes</sale> <msrp></msrp> <cube></cube> <weight></weight> <pricing> <tier> <pack><pack> <price></price> </tier> <tier> <pack><pack> <price></price> </tier> <tier> <pack><pack> <price></price> </tier> </pricing> </product> We sell in 3 different pack sizes hence the pricing node.

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  • Configuring MySQL Cluster Data Nodes

    - by Mat Keep
    0 0 1 692 3948 Homework 32 9 4631 14.0 Normal 0 false false false EN-US JA 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-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-ansi-language:EN-US;} In my previous blog post, I discussed the enhanced performance and scalability delivered by extensions to the multi-threaded data nodes in MySQL Cluster 7.2. In this post, I’ll share best practices on the configuration of data nodes to achieve optimum performance on the latest generations of multi-core, multi-thread CPU designs. Configuring the Data Nodes The configuration of data node threads can be managed in two ways via the config.ini file: - Simply set MaxNoOfExecutionThreads to the appropriate number of threads to be run in the data node, based on the number of threads presented by the processors used in the host or VM. - Use the new ThreadConfig variable that enables users to configure both the number of each thread type to use and also which CPUs to bind them too. The flexible configuration afforded by the multi-threaded data node enhancements means that it is possible to optimise data nodes to use anything from a single CPU/thread up to a 48 CPU/thread server. Co-locating the MySQL Server with a single data node can fully utilize servers with 64 – 80 CPU/threads. It is also possible to co-locate multiple data nodes per server, but this is now only required for very large servers with 4+ CPU sockets dense multi-core processors. 24 Threads and Beyond! An example of how to make best use of a 24 CPU/thread server box is to configure the following: - 8 ldm threads - 4 tc threads - 3 recv threads - 3 send threads - 1 rep thread for asynchronous replication. Each of those threads should be bound to a CPU. It is possible to bind the main thread (schema management domain) and the IO threads to the same CPU in most installations. In the configuration above, we have bound threads to 20 different CPUs. We should also protect these 20 CPUs from interrupts by using the IRQBALANCE_BANNED_CPUS configuration variable in /etc/sysconfig/irqbalance and setting it to 0x0FFFFF. The reason for doing this is that MySQL Cluster generates a lot of interrupt and OS kernel processing, and so it is recommended to separate activity across CPUs to ensure conflicts with the MySQL Cluster threads are eliminated. When booting a Linux kernel it is also possible to provide an option isolcpus=0-19 in grub.conf. The result is that the Linux scheduler won't use these CPUs for any task. Only by using CPU affinity syscalls can a process be made to run on those CPUs. By using this approach, together with binding MySQL Cluster threads to specific CPUs and banning CPUs IRQ processing on these tasks, a very stable performance environment is created for a MySQL Cluster data node. On a 32 CPU/Thread server: - Increase the number of ldm threads to 12 - Increase tc threads to 6 - Provide 2 more CPUs for the OS and interrupts. - The number of send and receive threads should, in most cases, still be sufficient. On a 40 CPU/Thread server, increase ldm threads to 16, tc threads to 8 and increment send and receive threads to 4. On a 48 CPU/Thread server it is possible to optimize further by using: - 12 tc threads - 2 more CPUs for the OS and interrupts - Avoid using IO threads and main thread on same CPU - Add 1 more receive thread. Summary As both this and the previous post seek to demonstrate, the multi-threaded data node extensions not only serve to increase performance of MySQL Cluster, they also enable users to achieve significantly improved levels of utilization from current and future generations of massively multi-core, multi-thread processor designs. A big thanks to Mikael Ronstrom, Senior MySQL Architect at Oracle, for his work in developing these enhancements and best practices. You can download MySQL Cluster 7.2 today and try out all of these enhancements. The Getting Started guides are an invaluable aid to quickly building a Proof of Concept Don’t forget to check out the MySQL Cluster 7.2 New Features whitepaper to discover everything that is new in the latest GA release

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  • Getting Perl DBD::mysql working on OS X 10.7?

    - by Bart B
    I can't seem to get Perl & MySQL to talk to each other on OS X 10.7 Lion. I did all the installs by the book, I used Oracle's PKG installer for the latest MySQL Community Server, and I installed DBI and DBD::mysql via CPAN. There were not problems at all during the install, but, when I try to USE DBD::mysql to connect to my local DB server I get the following error: install_driver(mysql) failed: Can't load '/Library/Perl/5.12/darwin-thread-multi-2level/auto/DBD/mysql/mysql.bundle' for module DBD::mysql: dlopen(/Library/Perl/5.12/darwin-thread-multi-2level/auto/DBD/mysql/mysql.bundle, 1): Library not loaded: /usr/local/mysql/lib/libmysqlclient.16.dylib Referenced from: /Library/Perl/5.12/darwin-thread-multi-2level/auto/DBD/mysql/mysql.bundle Reason: image not found at /System/Library/Perl/5.12/darwin-thread-multi-2level/DynaLoader.pm line 204. at (eval 3) line 3 Compilation failed in require at (eval 3) line 3. Perhaps a required shared library or dll isn't installed where expected After a lot of googling all I could find were suggested hacks, so I gave this one a go: http://arkoftech.wordpress.com/2011/02/10/fixing-dbdmysql-for-mysql-5-5-89-under-macos-10-6-x/ I had to update some of the paths in the instructions since on Lion it's Perl 5.12 not 5.10. After doing that I got a new error: dyld: lazy symbol binding failed: Symbol not found: _mysql_init Referenced from: /Library/Perl/5.12/darwin-thread-multi-2level/auto/DBD/mysql/mysql.bundle Expected in: flat namespace dyld: Symbol not found: _mysql_init Referenced from: /Library/Perl/5.12/darwin-thread-multi-2level/auto/DBD/mysql/mysql.bundle Expected in: flat namespace Trace/BPT trap: 5 There must be a simple way to get MySQL & Perl working on OS X? - HELP!

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  • How to install DBD::mysql on OS X Server 10.6?

    - by Zoran Simic
    Trying to install DBD::mysql on OS X Server 10.6 (mac mini server). But I'm missing the mysql headers apparently. Since mysql is already part of OS X Server 10.6, I would like to NOT install anything else (no fink or darwin ports installs), just whatever's needed to get DBD::mysql installed and working. Do you know how I could do that? Do I have to install the headers somewhere? And if so, where? (again: I don't want to install another version of mysql on the box, want to use the version it came with). Is there a way to install DBD::mysql without compiling any C files? This is the error I get (the actual error is much longer, but these are the most meaningful bits, this is the first error reported). Checking if your kit is complete... Looks good Unrecognized argument in LIBS ignored: '-pipe' Note (probably harmless): No library found for -lmysqlclient Multiple copies of Driver.xst found in: /Library/Perl/5.10.0/darwin-thread-multi-2level/auto/DBI/ /System/Library/Perl/Extras/5.10.0/darwin-thread-multi-2level/auto/DBI/ at Makefile.PL line 907 Using DBI 1.611 (for perl 5.010000 on darwin-thread-multi-2level) installed in /Library/Perl/5.10.0/darwin-thread-multi-2level/auto/DBI/ Writing Makefile for DBD::mysql cp lib/DBD/mysql.pm blib/lib/DBD/mysql.pm cp lib/DBD/mysql/GetInfo.pm blib/lib/DBD/mysql/GetInfo.pm cp lib/DBD/mysql/INSTALL.pod blib/lib/DBD/mysql/INSTALL.pod cp lib/Bundle/DBD/mysql.pm blib/lib/Bundle/DBD/mysql.pm gcc-4.2 -c -I/Library/Perl/5.10.0/darwin-thread-multi-2level/auto/DBI -I/usr/include -fno-omit-frame-pointer -pipe -D_P1003_1B_VISIBLE -DSIGNAL_WITH_VIO_CLOSE -DSIGNALS_DONT_BREAK_READ -DIGNORE_SIGHUP_SIGQUIT -DDBD_MYSQL_INSERT_ID_IS_GOOD -g -arch x86_64 -arch i386 -arch ppc -g -pipe -fno-common -DPERL_DARWIN -fno-strict-aliasing -I/usr/local/include -Os -DVERSION=\"4.014\" -DXS_VERSION=\"4.014\" "-I/System/Library/Perl/5.10.0/darwin-thread-multi-2level/CORE" dbdimp.c In file included from dbdimp.c:20: dbdimp.h:22:49: error: mysql.h: No such file or directory dbdimp.h:23:45: error: mysqld_error.h: No such file or directory dbdimp.h:25:49: error: errmsg.h: No such file or directory

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  • Error while installing boost_1_54

    - by Farhat
    On trying to install boost I get this error during configuration checks. Googling did not give any pointers. [root@heracles boost_1_54_0]# ./b2 install Performing configuration checks - 32-bit : no (cached) - 64-bit : yes (cached) - arm : no (cached) - mips1 : no (cached) - power : no (cached) - sparc : no (cached) - x86 : yes (cached) error: No best alternative for libs/coroutine/build/allocator_sources next alternative: required properties: <link>static <target-os>windows <threading>multi not matched next alternative: required properties: <link>static <segmented-stacks>on <threading>multi not matched next alternative: required properties: <link>static <threading>multi not matched - has_icu builds : no (cached) warning: Graph library does not contain MPI-based parallel components. note: to enable them, add "using mpi ;" to your user-config.jam - zlib : yes (cached) - iconv (libc) : yes (cached) - icu : no (cached) - icu (lib64) : no (cached) - compiler-supports-ssse3 : yes (cached) - compiler-supports-avx2 : no (cached) - gcc visibility : yes (cached) - long double support : yes (cached) warning: skipping optional Message Passing Interface (MPI) library. note: to enable MPI support, add "using mpi ;" to user-config.jam. note: to suppress this message, pass "--without-mpi" to bjam. note: otherwise, you can safely ignore this message. error: No best alternative for libs/coroutine/build/allocator_sources next alternative: required properties: <link>static <target-os>windows <threading>multi not matched next alternative: required properties: <link>static <segmented-stacks>on <threading>multi not matched next alternative: required properties: <link>static <threading>multi not matched - zlib : yes (cached) How can the alternative for allocator sources be located? Thanks.

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  • Partner Webcast – Oracle Coherence Applications on WebLogic 12c Grid - 21st Nov 2013

    - by Thanos Terentes Printzios
    Oracle Coherence is the industry leading in-memory data grid solution that enables organizations to predictably scale mission-critical applications by providing fast access to frequently used data. As data volumes and customer expectations increase, driven by the “internet of things”, social, mobile, cloud and always-connected devices, so does the need to handle more data in real-time, offload over-burdened shared data services and provide availability guarantees. The latest release of Oracle Coherence 12c comes with great improvements in ease of use, integration and RASP (Reliability, Availability, Scalability, and Performance) areas. In addition it features an innovating approach to build and deploy Coherence Application as an integral part of typical JEE Enterprise Application. Coherence GAR archives and Coherence Managed Servers are now first-class citizens of all JEE applications and Oracle WebLogic domains respectively. That enables even easier development, deployment and management of complex multi-tier enterprise applications powered by data grid rich features. Oracle Coherence 12c makes your solution ready for the future of big data and always-on-line world. This webcast is focused on demonstrating How to create a Coherence Application using Oracle Enterprise Pack for Eclipse 12.1.2.1.1 (Kepler release). How to package the application in form of GAR archive inside the EAR deployable application. How to deploy the application to multi-tier WebLogic clusters. How to define and configure the WebLogic domain for the tiered clusters hosting both data grid and client JEE applications.  Finally we will expose the data in grid to external systems using REST services and create a simple web interface to the underlying data using Oracle ADF Faces components. Join us on this technology webcast, to find out more about how Oracle Cloud Application Frameworks brings together the key industry leading technologies of Oracle Coherence and Weblogic 12c, delivering next-generation applications. Agenda: Introduction to Oracle Coherence What's new in 12c release POF annotations Live Events Elastic Data (Flash storage support) Managed Coherence Servers for Oracle WebLogic Coherence Applications (Grid Archive) Live Demonstration Creating and configuring Coherence Servers forming the data tier cluster Creating a simple Coherence Grid Application in Eclipse Adding REST support and creating simple ADF Faces client application Deploying the grid and client applications to separate tiers in WebLogic topology HA capabilities of the data tier Summary - Q&A Delivery Format This FREE online LIVE eSeminar will be delivered over the Web. Registrations received less than 24hours prior to start time may not receive confirmation to attend. Duration: 1 hour REGISTER NOW For any questions please contact us at partner.imc-AT-beehiveonline.oracle-DOT-com Stay Connected Oracle Newsletters

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  • MongoDB with OR and Range Indexes

    - by LMH
    I have a query: {"$query"=>{"user_id"=>"512f7960534dcda22b000491", "$or"=>[{"when_tz"=>{"$gte"=>2010-06-24 04:00:00 UTC, "$lt"=>2010-06-25 04:00:00 UTC}}, {"when_tz"=>{"$gte"=>2011-06-24 04:00:00 UTC, "$lt"=>2011-06-25 04:00:00 UTC}}, {"when_tz"=>{"$gte"=>2012-06-24 04:00:00 UTC, "$lt"=>2012-06-25 04:00:00 UTC}}], "_type"=>{"$in"=>["FacebookImageItem", "FoursquareImageItem", "InstagramItem", "TwitterImageItem", "Image"]}}, "$explain"=>true, "$orderby"=>{"when_tz"=>1}} And an index: { user_id: 1, _type: 1, when_tz: 1 } Explain: {"cursor"="BtreeCursor user_id_1__type_1_facebook_id_1 multi", "isMultiKey"=false, "n"=28, "nscannedObjects"=15094, "nscanned"=15098, "nscannedObjectsAllPlans"=181246, "nscannedAllPlans"=241553, "scanAndOrder"=true, "indexOnly"=false, "nYields"=12, "nChunkSkips"=0, "millis"=2869, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "_type"=[["FacebookImageItem", "FacebookImageItem"], ["FoursquareImageItem", "FoursquareImageItem"], ["Image", "Image"], ["InstagramItem", "InstagramItem"], ["TwitterImageItem", "TwitterImageItem"]], "facebook_id"=[[{"$minElement"=1}, {"$maxElement"=1}]]}, "allPlans"=[{"cursor"="BtreeCursor user_id_1__type_1_facebook_id_1 multi", "n"=28, "nscannedObjects"=15094, "nscanned"=15098, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "_type"=[["FacebookImageItem", "FacebookImageItem"], ["FoursquareImageItem", "FoursquareImageItem"], ["Image", "Image"], ["InstagramItem", "InstagramItem"], ["TwitterImageItem", "TwitterImageItem"]], "facebook_id"=[[{"$minElement"=1}, {"$maxElement"=1}]]}}, {"cursor"="BtreeCursor user_id_1__type_1_twitter_id_1 multi", "n"=28, "nscannedObjects"=15094, "nscanned"=15097, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "_type"=[["FacebookImageItem", "FacebookImageItem"], ["FoursquareImageItem", "FoursquareImageItem"], ["Image", "Image"], ["InstagramItem", "InstagramItem"], ["TwitterImageItem", "TwitterImageItem"]], "twitter_id"=[[{"$minElement"=1}, {"$maxElement"=1}]]}}, {"cursor"="BtreeCursor user_id_1__type_1_instagram_id_1 multi", "n"=28, "nscannedObjects"=15094, "nscanned"=15097, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "_type"=[["FacebookImageItem", "FacebookImageItem"], ["FoursquareImageItem", "FoursquareImageItem"], ["Image", "Image"], ["InstagramItem", "InstagramItem"], ["TwitterImageItem", "TwitterImageItem"]], "instagram_id"=[[{"$minElement"=1}, {"$maxElement"=1}]]}}, {"cursor"="BtreeCursor user_id_1__type_1_foursquare_id_1 multi", "n"=28, "nscannedObjects"=15094, "nscanned"=15097, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "_type"=[["FacebookImageItem", "FacebookImageItem"], ["FoursquareImageItem", "FoursquareImageItem"], ["Image", "Image"], ["InstagramItem", "InstagramItem"], ["TwitterImageItem", "TwitterImageItem"]], "foursquare_id"=[[{"$minElement"=1}, {"$maxElement"=1}]]}}, {"cursor"="BtreeCursor user_id_1_phash_1", "n"=21, "nscannedObjects"=15097, "nscanned"=15097, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "phash"=[[{"$minElement"=1}, {"$maxElement"=1}]]}}, {"cursor"="BtreeCursor user_id_1_aperature_1_shutter_speed_1_when_tz_1", "n"=25, "nscannedObjects"=35, "nscanned"=15097, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "aperature"=[[{"$minElement"=1}, {"$maxElement"=1}]], "shutter_speed"=[[{"$minElement"=1}, {"$maxElement"=1}]], "when_tz"=[[{"$minElement"=1}, {"$maxElement"=1}]]}}, {"cursor"="BtreeCursor user_id_1_image_hash_1", "n"=22, "nscannedObjects"=15097, "nscanned"=15097, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "image_hash"=[[{"$minElement"=1}, {"$maxElement"=1}]]}}, {"cursor"="BtreeCursor user_id_1_time_zone_guessed_1_when_tz_-1", "n"=23, "nscannedObjects"=32, "nscanned"=15097, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "time_zone_guessed"=[[{"$minElement"=1}, {"$maxElement"=1}]], "when_tz"=[[{"$maxElement"=1}, {"$minElement"=1}]]}}, {"cursor"="BtreeCursor user_id_1_time_zone_guessed_1_when_tz_1", "n"=24, "nscannedObjects"=33, "nscanned"=15097, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "time_zone_guessed"=[[{"$minElement"=1}, {"$maxElement"=1}]], "when_tz"=[[{"$minElement"=1}, {"$maxElement"=1}]]}}, {"cursor"="BtreeCursor user_id_1_time_zone_guessed_1_when_utc_-1", "n"=23, "nscannedObjects"=15097, "nscanned"=15097, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "time_zone_guessed"=[[{"$minElement"=1}, {"$maxElement"=1}]], "when_utc"=[[{"$maxElement"=1}, {"$minElement"=1}]]}}, {"cursor"="BtreeCursor user_id_1_time_zone_guessed_1_when_utc_1", "n"=24, "nscannedObjects"=15097, "nscanned"=15097, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "time_zone_guessed"=[[{"$minElement"=1}, {"$maxElement"=1}]], "when_utc"=[[{"$minElement"=1}, {"$maxElement"=1}]]}}, {"cursor"="BtreeCursor user_id_1_original_shared_item_id_1", "n"=24, "nscannedObjects"=15097, "nscanned"=15097, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "original_shared_item_id"=[[{"$minElement"=1}, {"$maxElement"=1}]]}}, {"cursor"="BtreeCursor user_id_1__type_1_s3_tmp_file_1 multi", "n"=28, "nscannedObjects"=15094, "nscanned"=15097, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "_type"=[["FacebookImageItem", "FacebookImageItem"], ["FoursquareImageItem", "FoursquareImageItem"], ["Image", "Image"], ["InstagramItem", "InstagramItem"], ["TwitterImageItem", "TwitterImageItem"]], "s3_tmp_file"=[[{"$minElement"=1}, {"$maxElement"=1}]]}}, {"cursor"="BtreeCursor user_id_1__type_1_processed_-1_uploaded_-1_image_device_1 multi", "n"=28, "nscannedObjects"=15094, "nscanned"=15097, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "_type"=[["FacebookImageItem", "FacebookImageItem"], ["FoursquareImageItem", "FoursquareImageItem"], ["Image", "Image"], ["InstagramItem", "InstagramItem"], ["TwitterImageItem", "TwitterImageItem"]], "processed"=[[{"$maxElement"=1}, {"$minElement"=1}]], "uploaded"=[[{"$maxElement"=1}, {"$minElement"=1}]], "image_device"=[[{"$minElement"=1}, {"$maxElement"=1}]]}}, {"cursor"="BtreeCursor user_id_1__type_1_when_tz_1 multi", "n"=28, "nscannedObjects"=28, "nscanned"=15097, "indexBounds"={"user_id"=[["512f7960534dcda22b000491", "512f7960534dcda22b000491"]], "_type"=[["FacebookImageItem", "FacebookImageItem"], ["FoursquareImageItem", "FoursquareImageItem"], ["Image", "Image"], ["InstagramItem", "InstagramItem"], ["TwitterImageItem", "TwitterImageItem"]], "when_tz"=[[{"$minElement"=1}, {"$maxElement"=1}]]}}, {"cursor"="BasicCursor", "n"=0, "nscannedObjects"=15097, "nscanned"=15097, "indexBounds"={}}], "server"=""} Any idea how to get it to hit the indexes?

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