Multithreading problems

Multithreading problems

[Ciorecan Marius]

Hi

    I have developed a multithreaded application that starts up to 100 - 200 threads. Each thread communicates on TCP/IP with some external process.
    The application is developed on C++, and it's running on an AIX machine, and compiled with gcc version 2.9-aix51-020209.

    When I have a higher load on the application, it crashes with core. I examined the core file with gdb and I see that most of the times it crashes in a socket operation OR when i throw an exception ( i throw exception for example when the communication with the partner is down on TCP/IP). 

    The exception part is very strange: i throw an exception and i have a catch in the caller function, but the exception never arrives to that catch. Is looking like the throw/catch functions are not thread safe.

    Do you have any idea? What should I look for? 
    
Marius

p.s. I compiled the sources with these flags: -D_REENTRANT -D_THREAD_SAFE -D_LIBC_REENTRANT -fexceptions -fstack-check

    

Re: Multithreading problems

[David Edelsohn]

	"GCC 2.9-aix" is a very old and non-standard version of GCC that
was not released or supported by the GCC Project.  Separately, there are
continuing efforts to make libstdc++ interaction with the underlying
operating system and libraries of target systems thread safe.

David

RE: Multithreading problems

[Daniel Kegel]

Ciorecan.Marius@ssi-schaefer.ro wrote:
 > is libstdc++ not thread safe?

The current versions of gcc come with versions of
libstdc++ that provide 'thread safety' as defined
in http://www.sgi.com/tech/stl/thread_safety.html, I think.
Note that this is not as 'thread safe' as Java's containers are.

It also doesn't mean you can't shoot yourself in
the foot with threads.
- Dan

RE: Multithreading problems

[Ciorecan Marius]

ok, I will try to install tomorrow some new version of gcc, i downloaded the one from http://www.bullfreeware.com/

also, is libstdc++ not thread safe?