Search Results

Search found 12802 results on 513 pages for 'memory profiler'.

Page 387/513 | < Previous Page | 383 384 385 386 387 388 389 390 391 392 393 394  | Next Page >

• SQLserver multithreaded locking with TABLOCKX

  - by WilfriedVS

  I have a table "tbluser" with 2 fields: userid = integer (autoincrement) user = nvarchar(100) I have a multithreaded/multi server application that uses this table. I want to accomplish the following: Guarantee that field user is unique in my table Guarantee that combination userid/user is unique in each server's memory I have the following stored procedure: CREATE PROCEDURE uniqueuser @user nvarchar(100) AS BEGIN BEGIN TRAN DECLARE @userID int SET nocount ON SET @userID = (SELECT @userID FROM tbluser WITH (TABLOCKX) WHERE [user] = @user) IF @userID <> '' BEGIN SELECT userID = @userID END ELSE BEGIN INSERT INTO tbluser([user]) VALUES (@user) SELECT userID = SCOPE_IDENTITY() END COMMIT TRAN END Basically the application calls the stored procedure and provides a username as parameter. The stored procedure either gets the userid or insert the user if it is a new user. Am I correct to assume that the table is locked (only one server can insert/query)?

  Read the article

• vector<vector<largeObject>> vs. vector<vector<largeObject>*> in c++

  - by Leif Andersen

  Obviously it will vary depending on the compiler you use, but I'm curious as to the performance issues when doing vector<vector<largeObject>> vs. vector<vector<largeObject>*>, especially in c++. In specific: let's say that you have the outer vector full, and you want to start inserting elements into first inner vector. How will that be stored in memory if the outer vector is just storing pointers, as apposed to storing the whole inner vector. Will the whole outer vector have to be moved to gain more space, or will the inner vector be moved (assuming that space wasn't pre-allocated), causing problems with the outer vector? Thank you

  Read the article

• C++ smart pointer for non-object type?

  - by Brian

  Hi, I'm trying to use smart pointers such as auto_ptr, shared_ptr. However, I don't know how to use it in this situation. CvMemStorage *storage = cvCreateMemStorage(); ... use the pointer ... cvReleaseMemStorage(&storage); I'm not sure, but I think that the storage variable is just malloc'ed memory, not object. Is there a way to use the smart pointers for the storage variable? Thank you.

  Read the article

• #define vs enum in an embedded environment (How do they compile?)

  - by Alexander Kondratskiy

  This question has been done to death, and I would agree that enums are the way to go. However, I am curious as to how enums compile in the final code- #defines are just string replacements, but do enums add anything to the compiled binary? Or are they both equivalent at that stage. When writing firmware and memory is very limited, is there any advantage, no matter how small, to using #defines? Thanks! EDIT: As requested by the comment below, by embedded, I mean a digital camera. Thanks for the answers! I am all for enums!

  Read the article

• Conseqences of assigning self

  - by Vegar

  Hi, Found a piece of code today, that I find a little smelly... TMyObject.LoadFromFile(const filename: String); begin if fileExists(filename) then self := TSomeObjectStreamer.ReadObjectFromFile(filename); end; If this code works, it will atleast leak some memory, but does it work? Is OK to assign to self in this manner? What if the streamed object is of a different subclass then the original self? What if the streamed object is of a different class with no common ancestore to the original self?

  Read the article

• Chaning coding style due to Android GC performance, how far is too far?

  - by Benju

  I keep hearing that Android applications should try to limit the number of objects created in order to reduce the workload on the garbage collector. It makes sense that you may not want to created massive numbers of objects to track on a limited memory footprint, for example on a traditional server application created 100,000 objects within a few seconds would not be unheard of. The problem is how far should I take this? I've seen tons of examples of Android applications relying on static state in order supposedly "speed things up". Does increasing the number of instances that need to be garbage collected from dozens to hundreds really make that big of a difference? I can imagine changing my coding style to now created hundreds of thousands of objects like you might have on a full-blown Java-EE server but relying on a bunch of static state to (supposedly) reduce the number of objects to be garbage collected seems odd. How much is it really necessary to change your coding style in order to create performance Android apps?

  Read the article

• Object sent -autorelease too many times

  - by mongeta

  I have this code that simple returns Today's date as a string formatted: +(NSString*) getTodayString_YYYY_MM_DD { NSDate * today = [NSDate date]; NSDateFormatter *formatter = [[NSDateFormatter alloc] init]; [formatter setDateFormat:@"yyyy-MM-dd"]; return [[formatter stringFromDate:today] autorelease]; } With instruments I'm not getting a memory leak, but when I Analyze, XCode says: Object sent -autorelease too many times If I understand correctly, I have to release manually the formatter as I'm creating it using 'alloc', but I can't release here because I have to return the value, so I add the autorelease. How I can do it better to improve it ? thanks, r.

  Read the article

• PHP: how to stop ignore_user_abort, is it a good solution for long run program

  - by user192344

  let say i have send email program which need to run arround 7 hours. but i cant open the browser for 7 hours beside cronjob, ignore_user_abort() will it be a solution? will the script stop when all email has sent and the program has finish the loop? or it will keep eating the server memory? some people said u may need to add some output at the end of the program to avoid the program run forever? and some people also said echo a litte bit string will not stop the script, but has to use ob_flush, any example for this?

  Read the article

• Compression Array of Bytes

  - by Pedro Magalhaes

  Hi, My problem is: I want to store a array of bytes in compressed file, and then I want to read it with a good performance. So I create a array of bytes then pass to a ZLIB algorithm then store it in the file. For my surprise the algorithm doesn't work well., probably because the array is a random sample. Using this approach, it will will be ber easy to read. Just copy the stream to memory, decompress them and copy it to a array of bytes. But i need to compress the file. Do I have to use a algorithm, like RLE, for compresse the byte array? I think that I can store the byte array like a string and then compress it. But i think I am going to have a poor performance on reading data. Sorry for my poor english. Thanks

  Read the article

• Java threadpool functionality

  - by cpf

  Hi stackoverflow, I need to make a program with a limited amount of threads (currently using newFixedThreadPool) but I have the problem that all threads get created from start, filling up memory at alarming rate. I wish to prevent this. Threads should only be created shortly before they are executed. e.g.: I call the program and instruct it to use 2 threads in the pool. The program should create & launch the first 2 Threads immediately (obviously), create the next 2 to wait for the previous 2, and at that point wait until one or both of the first 2 ended executing. I thought about extending executor or FixedThreadPool or such. However I have no clue on how to start there and doubt it is the best solution. Easiest would have my main Thread sleeping on intervals, which is not really good either... Thanks in advance!

  Read the article

• Returning references while using shared_ptrs

  - by Goose Bumper

  Suppose I have a rather large class Matrix, and I've overloaded operator== to check for equality like so: bool operator==(Matrix &a, Matrix &b); Of course I'm passing the Matrix objects by reference because they are so large. Now i have a method Matrix::inverse() that returns a new Matrix object. Now I want to use the inverse directly in a comparison, like so: if (a.inverse()==b) { ... }` The problem is, this means the inverse method needs to return a reference to a Matrix object. Two questions: Since I'm just using that reference in this once comparison, is this a memory leak? What happens if the object-to-be-returned in the inverse() method belongs to a boost::shared_ptr? As soon as the method exits, the shared_ptr is destroyed and the object is no longer valid. Is there a way to return a reference to an object that belongs to a shared_ptr?

  Read the article

• addObjectsFromArray

  - by derek.lo

  I have a question about memory management when using the addObjectsFromArray method. Basically, I have 2 arrays defined in the appDelegate. I need these 2 arrays for the duration of my application's runtime. I therefore release them in my appDelegate's dealloc method. When I go to use these two arrays in a class, I want one array to store the values from the other, so that the other can have it's contents removed, but still stick around for use. Something like this: [appDelegate.arrayTwo addObjectsFromArray:appDelegate.arrayOne]; [appDelegate.arrayOne removeAllObjects]; I'm getting the compiler error: EXC_BAD_ACCESS because of a pointer issue? retaining issue? Any help would be greatly appreciated! Thanks

  Read the article

• What interprocess locking calls should I monitor?

  - by Matt Joiner

  I'm monitoring a process with strace/ltrace in the hope to find and intercept a call that checks, and potentially activates some kind of globally shared lock. While I've dealt with and read about several forms of interprocess locking on Linux before, I'm drawing a blank on what to calls to look for. Currently my only suspect is futex() which comes up very early on in the process' execution. Update0 There is some confusion about what I'm after. I'm monitoring an existing process for calls to persistent interprocess memory or equivalent. I'd like to know what system and library calls to look for. I have no intention call these myself, so naturally futex() will come up, I'm sure many libraries will implement their locking calls in terms of this, etc. Update1 I'd like a list of function names or a link to documentation, that I should monitor at the ltrace and strace levels (and specifying which). Any other good advice about how to track and locate the global lock in mind would be great.

  Read the article

• Parsing XML stream in ASP.NET 3.5

  - by Ranjit

  Hi All, I am trying to build an ASP.NET 3.5 application based on XML streams from a legacy systems. My issue is once I get the XML I have to built menus and sub menus from the XML as well filter data(XML stream) based on the menu selection without making roundtrip to the Data store(legacy system). Right now I have a DAL which will get the XML stream in the form of XDocument.I was able to built the first level Menu Items, but not the sub Menu Items based on the selection in the Main Menu and then the final content based on the sub menu selection, all this without making a round trip. Is there a way to do this in-memory. Please suggest. thank you. Ranjit

  Read the article

• scala REPL is slow on vista

  - by Jacques René Mesrine

  I installed scala-2.8.0.RC3 by extracting the tgz file into my cygwin (vista) home directory. I made sure to set $PATH to scala-2.8.0.RC3/bin. I start the REPL by typing: $ scala Welcome to Scala version 2.8.0.RC3 (Java HotSpot(TM) Client VM, Java 1.6.0_20). Type in expressions to have them evaluated. Type :help for more information. scala> Now when I tried to enter an expression scala> 1 + 'a' the cursor hangs there without any response. Granted that I have chrome open with a million tabs and VLC playing in the background, but CPU utilization was 12% and virtual memory was about 75% utilized. What's going on ? Do I have to set the CLASSPATH or perform other steps.

  Read the article

• Good reasons why to not use XIB files?

  - by mystify

  Are there any good reasons why I should not use XIB / NIB files with an highly customized UI and extensive animations and super low memory footprint needs? As a beginner I started with XIB. Then I figured out I couldn't do just about everything in them. It started to get really hard to customize things the way I wanted them to be. So at the end, I threw all my XIBs away and did it all programmatically. So when someone asks me if XIB is good, I generally say: Yeah, if you want to make crappy boring interfaces and don't care too much about performance, go ahead. But what else could be a reason not to use XIB? Am I the only iPhone developer who prefers doing everything programmatically for this reasons?

  Read the article

• Are there any Python reference counting/garbage collection gotchas when dealing with C code?

  - by Jason Baker

  Just for the sheer heck of it, I've decided to create a Scheme binding to libpython so you can embed Python in Scheme programs. I'm already able to call into Python's C API, but I haven't really thought about memory management. The way mzscheme's FFI works is that I can call a function, and if that function returns a pointer to a PyObject, then I can have it automatically increment the reference count. Then, I can register a finalizer that will decrement the reference count when the Scheme object gets garbage collected. I've looked at the documentation for reference counting, and don't see any problems with this at first glance (although it may be sub-optimal in some cases). Are there any gotchas I'm missing? Also, I'm having trouble making heads or tails of the cyclic garbage collector documentation. What things will I need to bear in mind here? In particular, how do I make Python aware that I have a reference to something so it doesn't collect it while I'm still using it?

  Read the article

• Paging in ActiveRecord

  - by Alex

  Does CastleProject ActiveRecord support paging? I need to load only data which is now seen on the screen. If I use [HasMany], it will be loaded as a whole either immediately or at the first call (if lazy attribute is true). However I only need something like first 100 records (then maybe 100 next records). Another question is how to load only 100 items. If the collection is too big, memory can reach its limit if we constantly load more and more items.

  Read the article

• Change connection on the fly

  - by aron

  Hello, I have a SQL server with 50 databases. Each one has the exact same schema. I used the awesome Subsonic 2.2 create the DAL based on one of them. I need to loop though a list of database names and connect to each one and perform an update one at a time. If there a way to alter how subsonic uses the connection string. I believe I would need to store the connection string in memory that way it can keep changing. Is this possible? I tried doing a ConfigurationManager.ConnectionStrings["theConnStrName"].ConnectionString = updated-connection-string-here; .. but that did not work thanks!

  Read the article

• Clone LINQ To SQL object Extension Method throws object dispose exception....

  - by gtas

  Hello all, I have this extension method for cloning my LINQ To SQL objects: public static T CloneObjectGraph<T>(this T obj) where T : class { var serializer = new DataContractSerializer(typeof(T), null, int.MaxValue, false, true, null); using (var ms = new System.IO.MemoryStream()) { serializer.WriteObject(ms, obj); ms.Position = 0; return (T)serializer.ReadObject(ms); } } But while i carry objects with not all references loaded, while qyuerying with DataLoadOptions, sometimes it throws the object disposed exception, but thing is I don't ask for references that is not loaded (null). e.g. I have Customer with many references and i just need to carry on memory the Address reference EntityRef< and i don't Load anything else. But while i clone the object this exception forces me to load all the EntitySet< references with the Customer object, which might be too much and slow down the application speed. Any suggestions?

  Read the article

• Backing up my data causes my server to crash using Symantec Backup Exec 12, or How I Came to Loathe Irony

  - by Kyle Noland

  I have a Dell PowerEdge 2850 running Windows Server 2003. It is the primary file server for one of my clients. I have another server also running Windows Server 2003 that acts as the core media server for Symantec Backup Exec 12. I recently upgraded from Backup Exec 11d to 12. This upgrade was necessary because we also just upgraded from Exchange 2003 to Exchange 2007. After the upgrade I had to push-install the new version 12 Backup Exec Remote Agents to each of the servers I am backing up (about 6 total). 5 of my servers are doing just fine, faithfully completing backups every night. My file server routinely crashes. Observations: When the server crashes, it does not blue screen, it just locks up completely. Even the mouse is unresponsive. If you leave the server locked up long enough, it will eventually reboot itself and hang on the Windows splash screen. There is absolutely zero useful Event Viewer evidence of a problem. The logs go from routine logging to an Unexplained Shutdown Event the next morning when I have to hard reset the server to get it to boot. 90% of the time the server does not boot cleanly, it hangs on the Windows splash screen. I don't have any light to shed here. When the server hangs all I can do is hard reset it and try again. Even after a successful boot and chkdsk /r operation, if you reboot the machine, you have a 90% chance it won't back up again cleanly. The back story: This server started crashing during nightly backups about a month ago. I tried everything I could think of to troubleshoot the problem and eventually had to give up because I could not keep coming to the office at 4 AM to try to get the server back online. One Friday I got lucky and the server stayed up for its entire full backup. I took this opportunity to restore the full backup to a temporary server I set up and switched all my users to the temporary. Then I reloaded the ailing file server. I kept all my users on the temporary file server for about 3 weeks. I installed the same Backup Exec Remote Agent and Trend Micro A/V client on the temporary server that I was using on the regular file server. During this time, I had absolutely no problems backing up the temporary server. I tested the reloaded file server extensively. I rebooted the server once an hour every day for 3 weeks trying to make it fail. It never did. I felt confident that the reload was the answer to my problems. I moved all of the data from the temporary server back to the regular server. I got 3 nightly backups out of it before it locked up again and started the familiar failure to boot cleanly behavior. This weekend I decided to monitor the file server through the entire backup job. I RDPd into the file server and also into the server running Backup Exec. On the file server I opened the Task Manager so I could view the processes and watch CPU and memory usage. Everything was running smoothly for about 60GB worth of backup. Then I noticed that the byte count of the backup job in Backup Exec had stopped progressing. I looked back over at my RDP session into the file server, and I was getting real time updates about CPU and memory usage still - both nearly 0%, which is unusual. Backups usually hover around 40% usage for the duration of the backup job. Let me reiterate this point: The screen was refreshing and I was getting real time Task Manager updates - until I clicked on the Start menu. The screen went black and the server locked up. In truth, I think the server had already locked up, the video card just hadn't figured it out yet. I went back into my bag of trick: driving to the office and hard reseting the server over and over again when it hangs up at the Windows splash screen. I did this for 2 hours without getting a successful boot. I started panicking because I did not have a decent backup to use to get everything back onto the working temporary file server. Once I exhausted everything I knew to do, I took a deep breath, booted to the Windows Server 2003 CD and performed a repair installation of Windows. The server came back up fine, with all of my data intact. I can now reboot the server at will and it will come back up cleanly. The problem is that I'm afraid as soon as I try to back that data up again I will back at square one. So let me sum things up: Here is what I've done so far to troubleshoot this server: Deleted and recreated the RAID 5 sets. Initialized the drives. Reloaded the server with a fresh Server 2003 install. Confirmed with Dell that I have installed the latest, Dell approved BIOS and NIC drivers. Uninstalled / reinstalled the Backup Exec Remote Agent. Uninstalled the Trend Micro A/V client. Configured the server not to reboot itself after a blue screen so I can see any stop error. I used to think the server was blue screening, but since I enabled this setting I now know that the server just completely locks up. Run chkdsk /r from the Windows Recovery Console. Several errors were found and corrected, but did not help my problem. Help confirm or deny the following assumptions: There are two problems at work here. Why the server is locking up in the first place, and why the server won't boot cleanly after a lockup. This is ultimately a software problem. The server works fine and can be rebooted cleanly all day long - until the first lockup - following a fresh OS load or even a Repair installation. This is not a problem with Backup Exec in general. All of my other servers back up just fine. For the record, all of the other servers run Server 2003, and some of them house more data than the file server in question here. Any help is appreciated. The irony is almost too much to bear. Backing up my data is what is jeopardizing it.

  Read the article

• How to index a string like "aaa.bbb.ddd-fff" in Lucene?

  - by user46703

  Hi, I have to index a lot documents that contain reference numbers like "aaa.bbb.ddd-fff". The structure can change but it's always some arbitrary numbers or characters combined with "/","-","_" or some other delimiter. The users want to be able to search for any of the substrings like "aaa" or "ddd" and also for combinations like "aaa.bbb" or "ddd-fff". The best I have been able to come up with is to create my own token filter modeled after the synonym filter in "Lucene in action" which spits out multiple terms for each input. In my case I return "aaa.bbb", "bbb.ddd","bbb.ddd-fff" and all other combinations of the substrings. This works pretty well but when I index large documents (100MB) that contain lots of such strings I tend to get out of memory exceptions because my filter returns multiple terms for each input string. Is there a better way to index these strings?

  Read the article

• Plugin architecture in .net: unloading

  - by henchman

  Hello everybody, I need to implement a plugin architecture within c#/.net in order to load custom user defined actions data type handling code for a custom data grid / conversion / ... from non-static linked assembly files. Because the application has to handle many custom user defined actions, Iam in need for unloading them once executed in order to reduce memory usage. I found several good articles about plugin architectures, eg: ExtensionManager PluginArchitecture ... but none of them gave me enough sausage for properly unloading an assembly. As the program is to be distributed and the user defined actions are (as the name states) user defined: how to i prevent the assembly from executing malicious code (eg. closing my progra, deleting files)? Are there any other pitfalls one of you has encountered?

  Read the article

• How can I catch runtime error in C++

  - by Yan Cheng CHEOK

  By referring to http://stackoverflow.com/questions/315948/c-catching-all-exceptions try { int i = 0; int j = 0/i; /* Division by 0 */ int *k = 0; std::cout << *k << std::endl; /* De-reference invalid memory location. */ } catch (...) { std::cout << "Opps!" << std::endl; } The above run-time error are unable to be detected. Or, am I having wrong expectation on C++ exception handling feature?

  Read the article

• Application crashing in the iPad but working fine in iPad simulator.

  - by srikanth rongali

  Hi, I am writing a game in cocos2d. In the iPad Simulator the application is running good. While I am running the application in the iPad. But it was crashing by giving the following message in terminal. I am using 2048x2048 CCSpriteSheets in my code. I used instruments tool there is sudden increase in memory to 32MB before crashing. It is crashing at CCSpriteFrameCache . Program loaded. target remote-mobile /tmp/.XcodeGDBRemote-6258-64 Switching to remote-macosx protocol mem 0x1000 0x3fffffff cache mem 0x40000000 0xffffffff none mem 0x00000000 0x0fff none continue The program is not being run. The program is not being run. Thank you.

  Read the article

< Previous Page | 383 384 385 386 387 388 389 390 391 392 393 394  | Next Page >