I am running pstack to find function stack for my application running on two machines (both RHEL)
In one of my machine it is working as expected
[root@civ4cez191 bin]# pstack 22947 Thread 2 (Thread 0x7f63cbe7d700 (LWP 22949)): #0 0x0000003c3640f0cd in pause () from /lib64/libpthread.so.0 #1 0x0000000000485a78 in _signalWaitThread(void*) () #2 0x0000003c36407aa1 in start_thread () from /lib64/libpthread.so.0 #3 0x0000003c360e8aad in clone () from /lib64/libc.so.6 Thread 1 (Thread 0x7f63d2d07700 (LWP 22947)): #0 0x0000003c360e1523 in select () from /lib64/libc.so.6 #1 0x00000000004ccc36 in TFDSETSelect(void*, void*, int) () #2 0x00000000004cb50f in SvrInit1(unsigned int (*)(void*, void**), unsigned int (*)(void*, void*, void**, unsigned int*), void (*)(void*), unsigned int (*)(unsigned short, unsigned short), void (*)(unsigned short, unsigned short), void (*)(unsigned short, unsigned short), unsigned short, unsigned char, unsigned short, unsigned char) () #3 0x00000000004259f0 in main ()
However in other machine it is just printing name of the threads
[root@civ4cez194 bin]# pstack 12672 Thread 7 (Thread 0x7f01892e2700 (LWP 12674)): Thread 6 (Thread 0x7f0188aa0700 (LWP 12743)): Thread 5 (Thread 0x7f0188a1e700 (LWP 7090)): Thread 4 (Thread 0x7f0188a5f700 (LWP 7127)): Thread 3 (Thread 0x7f01889dd700 (LWP 7178)): Thread 2 (Thread 0x7f0188ae1700 (LWP 7235)): Thread 1 (Thread 0x7f0193ca0740 (LWP 12672)):
I have looked for a way to resolve this but haven't had much success. Only significant information I found was here
For thread information to be dumped, you have to use the debug-aware version of the LinuxThreads libpthread.so library. (To check, run nm(1) on your pthreads library, and make sure that the symbol "__pthread_threads_debug" is defined.) Threads are not supported with the newer NPTL libpthread.so library.
On doing nm on /lib64/libpthread.so.0 on both the machines, the only debug related field I could find was "__pthread_debug", however it is present in both.
Will appreciate help.