|
|
HP-UX Reference > Ppthread_default_stacksize_np(3T)Pthread LibraryHP-UX 11i Version 2: December 2007 Update |
|
NAMEpthread_default_stacksize_np() — change the default stacksize. PARAMETERS
DESCRIPTIONThe pthread_default_stacksize_np() function allows an application to change the default value for the stacksize attribute. This function must be called before any threads have been created. The new default stack size is passed in the new_size parameter. If not NULL, the previous default stack size is returned in old_size. If new_size is zero, this function can be used (at any time) to query the current default stack size. On HP-UX, threads with default stack sizes are cached after they terminate. The next time a thread is created with a default stack size, a cached thread (and its stack) are reused. This can result in significant performance improvements for pthread_create(). However, if the default stack size is not appropriate for an application, it cannot take advantage of this performance enhancement. By using the pthread_default_stacksize_np() function, the threads library will change the default stack size so that it matches the applications needs. This allows the application to utilize the performance benefit of cached threads. WARNINGIf the environment variable PTHREAD_DEFAULT_STACK_SIZE is set with valid value for default stack size, then it takes precedence over the invocation of the pthread_default_stacksize_np() interface. However, it returns current default stack size in old_size. Also, the maximum default stack size value that can be set through PTHREAD_DEFAULT_STACK_SIZE environment variable is restricted to 10 MB and any value above the same will be rounded off to 10 MB. Care should be taken while setting the default stack size limits as this could impact the maximum number of threads that can be created in a process. RETURN VALUEUpon successful completion, pthread_default_stacksize_np() returns zero. Otherwise, an error number is returned to indicate the error (the errno variable is not set). ERRORSIf any of the following occur, the pthread_default_stacksize_np() function returns the corresponding error number:
|
|