about greenplum collection tool

three collection tool for greenplum:pstack、strace、gcore.         
                                                                          
[gpadmin@gtlions5913 ~]$ ps -ef | grep postgres|grep data|grep master|grep -v grep
gpadmin   3653     1  0 May21 ?        00:00:00 /usr/local/greenplum-db-4.2.5.2/bin/postgres -D /data/master/gpseg-1 -p 5432 -b 1 -z 2 --silent-mode=true -i -M master -C -1 -x 0 -E
[gpadmin@gtlions5913 ~]$ pstack 3653
#0  0x00000034104ce183 in __select_nocancel () from /lib64/libc.so.6
#1  0x000000000087a63b in PostmasterMain ()
#2  0x000000000077ff3a in main ()
Copy the output to a file,or usage: pstack 3653 >pstack-gp.txt .


[gpadmin@gtlions5913 ~]$ strace -p 3653
Process 3653 attached - interrupt to quit
select(5, [3 4], NULL, NULL, {7, 897000}) = 0 (Timeout)
rt_sigprocmask(SIG_SETMASK, ~[ILL TRAP ABRT BUS FPE SEGV CONT SYS RTMIN RT_1], NULL, 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
select(5, [3 4], NULL, NULL, {60, 0} <unfinished ...>
Process 3653 detached
You must hole for at least 30 seconds and use "ctrl+c" to terminate. Copy the output to a file.


[gpadmin@gtlions5913 ~]$ gcore 3653
'import site' failed; use -v for traceback
Traceback (most recent call last):
  File "<string>", line 27, in ?
ImportError: No module named os.path
[Thread debugging using libthread_db enabled]
warning: no loadable sections found in added symbol-file system-supplied DSO at 0x7fffea126000
0x00000034104ce183 in __select_nocancel () from /lib64/libc.so.6
Saved corefile core.3653
-EOF-