Search Results

Search found 22961 results on 919 pages for 'memory management'.

Page 734/919 | < Previous Page | 730 731 732 733 734 735 736 737 738 739 740 741  | Next Page >

• delete & new in c++

  - by singh

  Hi This may be very simple question,But please help me. i wanted to know what exactly happens when i call new & delete , For example in below code char * ptr=new char [10]; delete [] ptr; call to new returns me memory address. Does it allocate exact 10 bytes on heap, Where information about size is stored.When i call delete on same pointer,i see in debugger that there are a lot of byte get changed before and after the 10 Bytes. Is there any header for each new which contain information about number of byte allocated by new. Thanks a lot

  Read the article

• How to find root cause for "too many connections" error in MySQL/PHP

  - by Nir

  I'm running a web service which runs algorithms that serve millions of calls daily and run some background processing as well. Every now and than I see "Too many connections" error in attempts to connect to the MySQL box" for a few seconds. However this is not necessarily attributed to high traffic times or anything I can put my finger on. I want to find the bottleneck causing it. Other than in the specific times this happens the server isn't too loaded in terms of CPU and Memory, and has 2-3 connections (threads) open and everything works smoothly. (I use Zabbix for monitoring) Any creative ideas on how to trace it?

  Read the article

• Mass data store with SQL SERVER

  - by Leo

  We need management 10,000 GPS devices, each GPS device upload a GPS data every 30 seconds, these data need to store in the database(MS SQL Server 2005). Each GPS device daily data quantity is: 24 * 60 * 2 = 2,880 10 000 10,000 GPS devices daily data quantity is: 10000 * 2880 = 28,800,000 Each GPS data approximately 160Byte, the amount of data per day is: 28,800,000 * 160 = 4.29GB We need hold at least 3 months of GPS data in the database, My question is: 1, whether SQL Server 2005 can support such a large amount of data store? 2, How to plan data table? (all GPS data storage in one table? Daily table? Each GPS device with a GPS data table?) The GPS data: GPSID varchar(21), RecvTime datetime, GPSTime datetime, IsValid bit, IsNavi bit, Lng float, Lat float, Alt float, Spd smallint, Head smallint, PulseValue bigint, Oil float, TSW1 bigint, TSW1Mask bigint, TSW2 bigint, TSW2Mask, BSW bigint, StateText varchar(200), PosText varchar(200), UploadType tinyint

  Read the article

• Database Compression in Python

  - by user551832

  I have hourly logs like user1:joined user2:log out user1:added pic user1:added comment user3:joined I want to compress all the flat files down to one file. There are around 30 million users in the logs and I just want the latest user log for all the logs. My end result is I want to have a log look like user1:added comment user2:log out user3:joined Now my first attempt on a small scale was to just do a dict like log['user1'] = "added comment" Will doing a dict of 30 million key/val pairs have a giant memory footprint.. Or should I use something like sqllite to store them.. then just put the contents of the sqllite table back into a file?

  Read the article

• Casting Class into String and Vice Versa in JAVA

  - by topgun_ivard

  I have a program in which I need to store a Class object into memory by casting it into String. Is it possible to convert the String back into the original Class so that I can use that class variables? I am doing this in JAVA. Example: test.java class hello{ public String h1; public String h2; } public class test { public static void main(String[] args) { hello h = new hello(); h.h1 = "hello"; h.h2 = "world"; String s = h.toString(); System.out.println("Print s : "+s); // Now I need to convert String s into type hello so that // I can do this: // (hello)s.h1; // (hello)s.h2; } } NOTE: this is not a homework, this is a personal project and I would be grateful if anyone can help! Thanks! Ivar

  Read the article

• Replacing the Import Table in PE file by standart LoadLibrary...

  - by user308368

  Hello. I have an executable (PE) file that load a dll file as represented in the Import table... let say: PEFile.exe Modules.dll my question is how can i remove Modules.dll's import_descriptor from the imports and do its work by loadLibrary without the rely on the import table and without destroy the file???... My bigger problem his i could not understand exactly how the Import thing works... after the loader read the information he needs to do the import's thing, i believe he use the LoadLibrary, GetProcAddress APIs... but i couldn't understated what he doing with the pointers he get... he putting them somewhere in memory... and then what just call them?!? all the papers i found in the net explain the structure of the import table, but i didn't found a paper that explain how it is really work and get used... i hope you cold understand my Gibberish English... Thank you!

  Read the article

• overloading new operator in c++

  - by Angus

  I have a code for best fit algorithm. I want to try to use the best fit algorithm using the operator new. Every time I create an object I should give it from the already allocated memory say, 1]20 2]12 3]15 4]6 5]23 respectively. which ever minimum amount fits to the objects size(eg.21) I wanted to do it for different object types, so I need to write the overloaded operator new to be common functionality for all the class objects. Can I do it through friend functions, or is there any possible way to do it.

  Read the article

• How to refresh database data only in SQL Server

  - by MaxGeek

  So I want to copy just the data from a Prod database (SQL 2005) down to my local machine (SQL 2005 & SQL 2008 Management Studio installed). The problem is I'm running into foreign key constraints that are causing the task/scripts to fail. I can get by these errors if I import certain tables first, but is there an easier way to do this all at once? I'm not a DBA so I don't have access to the database back up. I've tried the SQL Import/Export data Wizard and Publishing Wizard, but it also gets the PK error.

  Read the article

• Programatically determining file "size on disk" in advance

  - by porkchop

  I need to know how big a given in-memory buffer will be as an on-disk (usb stick) file before I write it. I know that unless the size falls on the block size boundary, its likely to get rounded up, e.g. a 1 byte file takes up 4096 bytes on-disk. I'm currently doing this using GetDiskFreeSpace() to work out the disk block size, then using this to calculate the on-disk size like this: GetDiskFreeSpace(szDrive, &dwSectorsPerCluster, &dwBytesPerSector, NULL, NULL); dwBlockSize = dwSectorsPerCuster * dwBytesPerSector; if (dwInMemorySize % dwBlockSize != 0) { dwSizeOnDisk = ((dwInMemorySize / dwBlockSize) * dwBlockSize) + dwBlockSize; } else { dwSizeOnDisk = dwInMemorySize; } Which seems to work fine, BUT GetDiskFreeSpace() only works on disks up to 2GB according to MSDN. GetDiskFreeSpaceEx() doesn't return the same information, so my question is, how else can I calculate this information for drives 2GB? Is there an API call I've missed? Can I assume some hard values depending on the overall disk size?

  Read the article

• What could cause a returning function to crash? C++

  - by JeanOTF

  So I have been debugging this error for hours now. I writing a program using Ogre3d relevant only because it doesn't load symbols so it doesn't let me stack trace which made finding the location of the crash even harder. So, write before I call a specific function I print out "Starting" then I call the function and immediately after I print "Stopping". Throughout the function I print out letters A-F where F is printed right before the function returns (one line above the last '}') The weird thing is when the crash occurs it is after the 'F' is printed but there is no 'Stopping'. Does this mean that the crash is happening in between somewhere? The only thing I can think of is something going wrong during the deallocation of some of the memory allocated during the function. I've never had anything happen like this, I will keep checking to make sure it's going wrong where I think it is.

  Read the article

• SQL Server Compact Edition 3.5 performance

  - by Wili

  I am using SQL Server CE 3.5 SP1 in one of my client applications. When a user loads the program and starts using it, performance is fine. If the user lets the program sit idle for a while, it takes a considerable amount of time (10 or more seconds) for the program to respond. Every time the user asks for a new screen, a call is made to the SQL CE database to get the data for that screen. It seems like the hard drive may be going to sleep and then when the database is accessed, the hard drive has to wake back up. Is it possible to load the entire database into memory and work from that? Are there any other suggestions on how to increase performance?

  Read the article

• Aptana Studio is opening but not ever closing a python.exe process

  - by SC Ghost

  I am developing a small testing website using Django 1.2 in Aptana Studio build 2.0.4.1268158907. I have a Django project that I test by running the command "runserver 8001" on my project. This command runs the project on a small server that comes with Django. However the problem arises that every time I run this command Aptana opens two instances of the process "python.exe". Upon terminating the command only one of these instances is ended. The other process continues to run and use memory. My server is not online, and the process doesn't seem to do anything that I can find. This happens every time i run the runserver command on my project and therefore more and more python.exe instances will open up through my development period. Any help discovering either the purpose of this extra python.exe or a way to prevent it from opening would be much appreciated.

  Read the article

• is it possible to write data to a collection in wpf?

  - by randyc

  Hello. In looking through samples I have seen a number of examples where it is possible to present data within a wpf applicaiton by binding to collections. However I was wondering is it possible to write to a collection from an applicaiton. Say for example i have 2 or more fields such as names and I wanted to have hte ability to add up to three names in my application ( all stored in memory). Will collections serve this purpose. In the past with asp.net I have done this by creating data tables and storing values on the fly or during the session. I am trying to learn WPF and I was wondering if collections work in the same fashion? If so could you please post an example or point me to references that show examples of this? Thank you in advance.

  Read the article

• Missing something with Entity Framework for .NET 3.5?

  - by AC

  Is it not possible to have EF create the necessary entities when I have two related tables linked with a FK in .NET3.5SP1? I see where the checkbox to support this is disabled but it is available in .NET4. I've got a DB that has only tables with relationships in it. I need to build a Silverlight app (SL4) that allows management of the data within this app. I can't use .NET4 on the server... only .NET3.5SP1 so FK relationship bit in EF4 isn't available to me. Looking to avoid building as much of the plumbing to get back to the DB from the SL4 app as possible...

  Read the article

• Hibernate Hql find result size for paginator

  - by KCore

  Hi, I need to add paginator for my Hibernate application. I applied it to some of my database operations which I perform using Criteria by setting Projection.count().This is working fine. But when I use hql to query, I can't seem to get and efficient method to get the result count. If I do query.list().size() it takes lot of time and I think hibernate does load all the objects in memory. Can anyone please suggest an efficient method to retrieve the result count when using hql?

  Read the article

• What is the best way to do multiple listviews in android?

  - by Nicos

  Hi all, i am writing a software that i have to drill down on content a lot. For example when the program starts a listview is displayed. When user clicks on an item, then a second listview must be displayed. For example: Select Continent Select Country Select State Select City Select Address What is the best way to do this (less memory, faster, easier to code etc)? To create multiple listviews with multiple adapters? Or 1 listview with multiple Adapters? Lists are loaded from an external XML File. So far i am creating a new adapter and setting it to the listview. How do i create a second listview and after clicking on 1st listview displaying the second one, with animation. Any examples? Extend my class to ListActivity or Activity? Best regards and thanks for helping, Nicos

  Read the article

• Zend Namespace - Check if Session Exists

  - by Vincent

  All, I am using Zend Framework and Zend_Session to do global session management for my application. I plan to clear all sessions on logout and hence am using the following code: if($this->sessionExists()) { $this->destroy(); } But it seems like it's not doing a good job.. I am getting an error: PHP Warning: session_destroy() [<a href='function.session-destroy'> function.session-destroy</a>]: Trying to destroy uninitialized session How can I get rid of this error? Is there an alternative to sessionExists()?

  Read the article

• Reading files with Java

  - by sikas

  I would like to know how can I read a file byte by byte then perform some operation every n bytes. for example: Say I have a file of size = 50 bytes, I want to divide it into blocks each of n bytes. Then each block is sent to a function for some operations to be done on those bytes. The blocks are to be created during the read process and sent to the function when the block reaches n bytes so that I don`t use much memory for storing all blocks. I want the output of the function to be written/appended on a new file. This is what I've reached to read, yet I don't know it it is right: fc = new JFileChooser(); File f = fc.getSelectedFile(); FileInputStream in = new FileInputStream(f); byte[] b = new byte[16]; in.read(b); I haven't done anything yet for the write process.

  Read the article

• What is the best way to expose a callback API - C++

  - by rursw1

  Hi, I have a C++ library that should expose some system\ resource calls as callbacks from the linked application. For example: the interfacing application (which uses this library) can send socket management callback functions - send, receive, open, close etc., and the library will use this implementation in stead of the library's implementation. (This way enables the application to manage the sockets by itself, can be useful). This library has to expose also more callbacks, like, for example, a password validation, so I wonder if there is a preferred method to expose the callback sending option in one API. Something like: int AddCallbackFunc (int functionCallbackType, <generic function prototype>, <generic way to pass some additional arguments>) Then within my library I will assign the callback to the appropriate function pointer according to the functionCallbackType parameter. Is there any way to implement it in a generic way which will fit ANY function prototype and ANY additional arguments? Your help will be more than appreciated... Thanks!

  Read the article

• C++ boost thread id and Singleton

  - by aaa

  hi. Sorry to flood so many questions this week. I assume thread index returned by thread.get_id is implementation specific. In case of the pthreads, is index reused? IE, if thread 0 runs and joins, is thread launched afterwords going to have a different ID? the reason I ask this is a need to implement Singleton pattern with a twist: each thread gets its own instance. I know it sounds very crazy, but threads control hardware (cuda) which does not permit device memory sharing. What is a good way to implement such pattern?

  Read the article

• Retrieving Large Lists of Objects Using Java EE

  - by hallidave

  Is there a generally-accepted way to return a large list of objects using Java EE? For example, if you had a database ResultSet that had millions of objects how would you return those objects to a (remote) client application? Another example -- that is closer to what I'm actually doing -- would be to aggregate data from hundreds of sources, normalize it, and incrementally transfer it to a client system as a single "list". Since all the data cannot fit in memory, I was thinking that a combination of a stateful SessionBean and some sort of custom Iterator that called back to the server would do the trick. How have you successfully solved this problem in the past?

  Read the article

• How do I read UTF-8 characters via a pointer?

  - by Jen

  Suppose I have UTF-8 content stored in memory, how do I read the characters using a pointer? I presume I need to watch for the 8th bit indicating a multi-byte character, but how exactly do I turn the sequence into a valid Unicode character? Also, is wchar_t the proper type to store a single Unicode character? This is what I have in mind: wchar_t readNextChar (char** p) { char ch = *p++; if (ch & 128) { // This is a multi-byte character, what do I do now? // char chNext = *p++; // ... but how do I assemble the Unicode character? ... } ... }

  Read the article

• Porting existing code from C# 2.0 to C#3.0 and .Net 3.5 (possibly .net 4.0)

  - by kanad

  Our one and only enterprise application suite has been developed over last 3 years using C# 2.0 on .Net 3.0. We use winforms and WCF heavily. The development tools is VS 2005 Pro / TFS 2005 / Resharper 3.1 As technical lead I obviously understand the benefits in a move to C#3.0 and .Net 3.5. But I want to convince management for a move to C#3.0, .Net 3.5, VS 2008 and TFS 2008. They will obviously be interested in things like productivity, cost, quality etc. Please suggest me some ideas on how best to make my case. Given that this may not happen till mid next year am I better off to hold till VS 2010 and .Net 4.0 is out.

  Read the article

• List show/add/remove View

  - by Michael

  Looking for some best practices of UI list on iPhone which has item add/modify/delete functions. Please refer to some sample codes or articles to build user friendly interface. The main application is tab bar application and one of the tabs supposed to show item management. The item itself consisting of 3 text items, first one can be label, it's short, the rest if it's not terribly complicated I would like to show below with small font or show when user taps on item entering edit mode... Not sure how to design all this and which views to use.

  Read the article

• Why don't hardware failures show up at the programming language level?

  - by Julian Cienfuegos

  I am wondering if anyone can give my a good answer, or at least point me in the direction of a good reference to the following question: How come I have never heard of a computer breaking in a very fundamental way? How come when I declare x to be a double it stays as a double? How come there is never a short circuit that robs it of some bytes and makes it an integer? Why do we have faith that when we initialize x to 10, there will never be a power surge that will cause it to become 11, or something similar? I think I need a better understanding of memory. Thanks, and please don't bash me over the head for such a simple/abstract question.

  Read the article

< Previous Page | 730 731 732 733 734 735 736 737 738 739 740 741  | Next Page >