Hi, I have an application which uses a homegrown tasking mechanism. Basically, it uses setjmp/longjmp where the stackpointer is modified after the setjmp and before the longjmp. This allows multiple 'tasks' to run (serially) within the process with each having a different stack allocation. The above process is then run on top of a single pthreads thread. With the newer pthreads libraries, this code nolonger works: Fatal error 'longjmp()ing between thread contexts is undefined by POSIX 1003.1' at line ? in file /usr/src/lib/libc_r/uthread/uthread_jmp.c (errno = ?) Fatal error 'longjmp()ing between thread contexts is undefined by POSIX 1003.1' at line ? in file /usr/src/lib/libc_r/uthread/uthread_jmp.c (errno = ?) Instead of possibly modifying the pthreads library, I decided to convert the homegrown tasking to simply always use pthreads. I have this working, unfortunately, the performance of this implementation is much slower: setjmp/longjmp: initialization time: real time 0.12 seconds cpu time 0.08 seconds pthreads: initialization time: real time 0.82 seconds cpu time 0.79 seconds About a 7x performance loss. I am using 'pthread_cond_signal()' to activate each successive thread thus avoiding the overhead of a 'pthread_cond_broadcast()'. Pthread_setschedparam() doesn't seem to have any effect. Two questions: Has anyone dealt with type of problem before? If so, what approach did you take? Has anyone thought of adding/implementing a (not posix standard) way of informing pthreads to allow multiple stacks to be swapped in and out on a single pthreads thread (thus allowing the previously accepted semantics to continue working?) Thanks, John To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
