[omniORB]The omnithread problem and solution

[Алексей Иваненко]

Hello All. My name is Alexey and i have a question. Recently i came across some omnithread problem. I am developing an application which uses CORBA of course and about 179 omnithreads. But when my application makes 166 threads  omni throw an exception omni_thread_fatal. I think that reason of this problem is fulfilled of stack. I've modified program code of omnithread library and it works. First of all i want to show my solution and ask why omniORB developers didn't make something like that? Maybe there were some problems, which i don't know. I've tested it and it worked fine. But maybe there will be situations where it will be cause of  problems. If so i will be glad to know that.

I am using omniORB-4.0.5 (but i saw source cod of omniORB-4.1.2 where the same style of thread creation). My application works in Linux, so i have modified POSIX.cc (i attached it to this letter).

Main idea: When there isn't enough space in process address space to allocate mammary for thread stack, it will be allocated by using malloc() function.

Details:              
 
 ************First i've added 2 variables
  
  void * stack_ptr=0; <- stack pointer for a new thread 
  size_t stack_size_def = 32768; <- size of a new stack 
 
 ************In start function i've made following canges:
 
 if (PthreadDraftVersion == 4)
     if (pthread_create(&posix_thread, &attr, omni_thread_wrapper,(void*)this)!=0) <-create until enough mammary if not  enough stack space then
        
     {
      if (stack_size)
      { 
         stack_ptr=malloc(stack_size); <-allocate mammary for new thread; 
         stack_size_def=stack_size;   
      {
      else stack_ptr=malloc(stack_size_def);
      if (stack_ptr)
       {
         THROW_ERRORS (pthread_attr_setstack(&attr,stack_ptr,stack_size_def));<-define where stack will be 
         THROW_ERRORS (pthread_create(&posix_thread, &attr, omni_thread_wrapper,(void*)this));<-and create thread  
       }
      else throw omni_thread_fatal(errno);
     }
     pthread_attr_delete(&attr);
 #else
     if (pthread_create(&posix_thread, &attr, omni_thread_wrapper,(void*)this)!=0)
     {
      if (stack_size)
      { 
         stack_ptr=malloc(stack_size); 
         stack_size_def=stack_size;   
      {
      else stack_ptr=malloc(stack_size_def);
      if (stack_ptr)
      {
        THROW_ERRORS (pthread_attr_setstack(&attr,stack_ptr,stack_size_def));
        THROW_ERRORS (pthread_create(&posix_thread, &attr, omni_thread_wrapper,(void*)this));
      }
      else throw omni_thread_fatal(errno);
     }
 
     pthread_attr_destroy(&attr);
 #endif
 ********** In exit function i've added:
 if (stack_ptr) free(stack_ptr);
 
 
 I'll be grateful if you'll answer me. 
 
 
 


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