Hi, I find if I use a defined stack size to create a child thread, then the max stack size from /proc/pid/task/child pid/limits still shows "Max stack size 8388608", it doesn't update to the user defined size, is it a problem? Here is the test code: ... pthread_attr_t attr; ret = pthread_attr_init(&attr); if (ret) printf("error\n"); ret = pthread_attr_setstacksize(&attr, 83886080); if (ret) printf("error\n"); ret = pthread_create(&id_1[i], &attr, (void *)thread_alloc, NULL); ... I use strace to track the app, it shows glibc will call mmap to alloc the child thread stack. So should gilbc call setrlimit to update the stack limit too? And glibc will only insert a guard at the start of the stack vma, so the stack vma maybe merged to another vma at the end, right? ... mmap(NULL, 83890176, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_STACK, -1, 0) = 0x7fca1d6a6000 mprotect(0x7fca1d6a6000, 4096, PROT_NONE) = 0 clone(child_stack=0x7fca226a5fb0, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, parent_tidptr=0x7fca226a69d0, tls=0x7fca226a6700, child_tidptr=0x7fca226a69d0) = 21043 ... Thanks, Xishi Qiu -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>