Re: BUG #16145: Not able to terminate active session

Dear Mahendra & Tomas

Please find the updated output of bdf command. Please let me know if you
need additional log.

(gdb) bt
#0  0x00007f5503e826e0 in __read_nocancel () from /lib64/libpthread.so.0
#1  0x00007f54eb392490 in snttread () from
/db/oraclnt/12.2.0/lib/libclntsh.so.12.1
#2  0x00007f54eb391420 in nttfprd () from
/db/oraclnt/12.2.0/lib/libclntsh.so.12.1
#3  0x00007f54eb387be0 in nsbasic_brc () from
/db/oraclnt/12.2.0/lib/libclntsh.so.12.1
#4  0x00007f54eb37e654 in nioqrc () from
/db/oraclnt/12.2.0/lib/libclntsh.so.12.1
#5  0x00007f54eb3987f9 in ttcdrv () from
/db/oraclnt/12.2.0/lib/libclntsh.so.12.1
#6  0x00007f54eb382809 in nioqwa () from
/db/oraclnt/12.2.0/lib/libclntsh.so.12.1
#7  0x00007f54eb36ce90 in upirtrc () from
/db/oraclnt/12.2.0/lib/libclntsh.so.12.1
#8  0x00007f54eb378f86 in kpurcsc () from
/db/oraclnt/12.2.0/lib/libclntsh.so.12.1
#9  0x00007f54eb3710c9 in kpuexec () from
/db/oraclnt/12.2.0/lib/libclntsh.so.12.1
#10 0x00007f54eb36c639 in OCIStmtExecute () from
/db/oraclnt/12.2.0/lib/libclntsh.so.12.1
#11 0x00007f54ec10eb32 in oracleExecuteQuery (session=0x1a16838,
oraTable=0x1a0e558, paramList=<optimized out>) at oracle_utils.c:1964
#12 0x00007f54ec105940 in oracleIterateForeignScan (node=<optimized out>)
at oracle_fdw.c:1432
#13 0x000000000062e58b in ForeignNext ()
#14 0x000000000060c2fa in ExecScan ()
#15 0x000000000061d90d in ExecHashJoin ()
#16 0x00000000006280af in ExecNestLoop ()
#17 0x000000000060401a in standard_ExecutorRun ()
#18 0x000000000074615b in PortalRunSelect ()
#19 0x000000000074751f in PortalRun ()
#20 0x0000000000744e6d in PostgresMain ()
#21 0x00000000004803e9 in ServerLoop ()
#22 0x00000000006d7b99 in PostmasterMain ()
#23 0x000000000048124f in main ()


Regards

Mohan

6670 4751


On Wed, Dec 4, 2019 at 2:22 AM Mahendra Singh <[email protected]> wrote:

> Hi Mohan,
> Please follow below steps to get stack trace(call stack/back trace) of
> postgres process.
>
> Step1)
> Fire "ps -aef | grep postgres" and identify the process id or PID of
> client.
>
> Ex:
> [mahendra@localhost bin]$ ps -aef | grep postgres
> mahendra 104917      1  0 23:40 ?        00:00:00
> /home/mahendra/postgres_base_rp/postgres/inst/bin/postgres -D data
> mahendra 104920 104917  0 23:40 ?        00:00:00 postgres: checkpointer
> mahendra 104921 104917  0 23:40 ?        00:00:00 postgres: background
> writer
> mahendra 104922 104917  0 23:40 ?        00:00:00 postgres: walwriter
> mahendra 104923 104917  0 23:40 ?        00:00:00 postgres: stats
> collector
> mahendra 104924 104917  0 23:40 ?        00:00:00 postgres: logical
> replication launcher
> mahendra *105137*   6320  0 23:44 pts/1    00:00:00 ./psql postgres
> mahendra 105138 104917  0 23:44 ?        00:00:00 postgres: mahendra
> postgres [local] idle
> mahendra 105165   6859  0 23:44 pts/2    00:00:00 grep --color=auto
> postgres
> [mahendra@localhost bin]$
>
> Here, my session id is 105137 (pid) means I connected as a client from
> server with 105137 PID.
>
> Step2)
> Now attach your PID using gdb.
>
> Ex:
> [mahendra@localhost bin]$ gdb attach 105137
> GNU gdb (GDB) Red Hat Enterprise Linux 7.6.1-110.el7
> -------------some more gdb info will be printed
>
> Step3) Now fire "bt" or "backtrace" command.
>
> Note: Don't exit the gdb from step2.
>
> 81 T_PSEUDO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS)
> Missing separate debuginfos, use: debuginfo-install
> keyutils-libs-1.5.8-3.el7.x86_64 krb5-libs-1.15.1-19.el7.x86_64
> libcom_err-1.42.9-12.el7_5.x86_64 libselinux-2.5-12.el7.x86_64
> ncurses-libs-5.9-14.20130511.el7_4.x86_64 openssl-libs-1.0.2k-12.el7.x86_64
> pcre-8.32-17.el7.x86_64 readline-6.2-10.el7.x86_64 zlib-1.2.7-17.el7.x86_64
> (gdb)
> (gdb*) bt*
> #0  0x00007ffa46e517e0 in __read_nocancel () at
> ../sysdeps/unix/syscall-template.S:81
> #1  0x00007ffa46c27097 in rl_getc () from /lib64/libreadline.so.6
> #2  0x00007ffa46c278e7 in rl_read_key () from /lib64/libreadline.so.6
> #3  0x00007ffa46c12b2f in readline_internal_char () from
> /lib64/libreadline.so.6
> #4  0x00007ffa46c131e5 in readline () from /lib64/libreadline.so.6
> #5  0x00000000004381a6 in gets_interactive (prompt=0x6f6a60
> <destination.7461> "postgres=# ", query_buf=0x1a37b00) at input.c:92
> #6  0x000000000043a9a0 in MainLoop (source=0x7ffa466ed640
> <_IO_2_1_stdin_>) at mainloop.c:169
> #7  0x000000000044ac5d in main (argc=2, argv=0x7ffefd61e818) at
> startup.c:441
> (gdb)
>
> Thanks and Regards
> Mahendra Thalor
> EnterpriseDB: http://www.enterprisedb.com
>
> On Tue, 3 Dec 2019 at 22:08, Tomas Vondra <[email protected]>
> wrote:
>
>> On Wed, Dec 04, 2019 at 12:26:14AM +0800, MOHAN KUMAR DORAIRAJ wrote:
>> >Dear Tomas
>> >
>> >Please find the info
>> >
>> >
>> >-bash-4.2$ gdb -p 16647
>> >GNU gdb (GDB) Red Hat Enterprise Linux 7.6.1-115.el7
>> >Copyright (C) 2013 Free Software Foundation, Inc.
>> >License GPLv3+: GNU GPL version 3 or later <
>> http://gnu.org/licenses/gpl.html
>> >>
>> >This is free software: you are free to change and redistribute it.
>> >There is NO WARRANTY, to the extent permitted by law.  Type "show
>> copying"
>> >and "show warranty" for details.
>> >This GDB was configured as "x86_64-redhat-linux-gnu".
>> >For bug reporting instructions, please see:
>> ><http://www.gnu.org/software/gdb/bugs/>.
>> >Attaching to process 16647
>> >Reading symbols from /usr/pgsql-11/bin/postgres...Reading symbols from
>> >/usr/pgsql-11/bin/postgres...(no debugging symbols found)...done.
>> >(no debugging symbols found)...done.
>> >Reading symbols from /lib64/libpthread.so.0...(no debugging symbols
>> >found)...done.
>> >[Thread debugging using libthread_db enabled]
>> >Using host libthread_db library "/lib64/libthread_db.so.1".
>> >...
>> >Reading symbols from /db/oraclnt/12.2.0/lib/libnque12.so...(no debugging
>> >symbols found)...done.
>> >Loaded symbols for /db/oraclnt/12.2.0/lib/libnque12.so
>> >0x00007f5503e826e0 in __read_nocancel () from /lib64/libpthread.so.0
>> >Missing separate debuginfos, use: debuginfo-install
>> >postgresql11-server-11.2-2PGDG.rhel7.x86_64
>> >(gdb) quit
>> >A debugging session is active.
>> >
>> >        Inferior 1 [process 16647] will be detached.
>> >
>> >Quit anyway? (y or n) y
>> >Detaching from program: /usr/pgsql-11/bin/postgres, process 16647
>> >
>>
>> This is still just the initial info gdb shows after attaching to the
>> process. You need to do "bt" or "backtrace" before quitting.
>>
>>
>> regards
>>
>> --
>> Tomas Vondra                  http://www.2ndQuadrant.com
>> PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
>>
>>
>>