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Showing posts from April, 2007

Java JVM high memory usage problems

Though I have some three four years experience in C++ ,I did not have that much oppurtunity to work in Java. Currenly I was doing some analysis for a very simple CLI and was surprised to come with a memory restriction. I found that if I use Java for developing the CLI application I will be exhausting the memory of our Application Server (AS). Just to mention the architecture ,users (telecom operators) use a metaframe server client ( =something like remote desktop) to login to the AS and then open a GUI to work on it. With Java I can service only about 15 clients with the available memory . I just checked the reason for this resource crunch and found that already many Java based GUI's are served by the AS and each is taking some 25 MB or more. The first thing I thought is that adding more RAM will solve this ( though this is not an easy option) . Then I understood that a 32 bit system can have just about 3 gb ram for applciations and our AS had already 4 GB with 1.5 GB VM also co

Windebug and Adplus for debugging process hang

1. Set the symbol, especillay windows symbols .......26_Merged\UNCRelease;\\blrm2fsp\SCSD-Common\Sym\WinSym2K3SP1 2. Set the souce and image 3. Load the extension dll ( for !locks command ) if not already loaded .load C:\Program Files\Debugging Tools for Windows\winxp\kdexts.dll 4. Use the !ntsdexts.locks ( or !locks ) command to see a list of critical section :004> !ntsdexts.locks CritSec ntdll!LdrpLoaderLock +0 at 7C889D94 LockCount -6902 RecursionCount 1 OwningThread 2b3c EntryCount 0 ContentionCount 28f3 *** Locked CritSec +12f9b4 at 0012F9B4 LockCount 0 RecursionCount 0 OwningThread 0 *** Locked CritSec +12f70c at 0012F70C LockCount 0 RecursionCount 0 OwningThread 0 *** Locked CritSec +128202c at 0128202C LockCount -2 RecursionCount 1 OwningThread 3d9c EntryCount 0 ContentionCount 0 *** Locked ----------- A 'LockCount' other than 0 means that many threads are waitiing on t