BUG #7885: postmaster panic on startup does not release shared memory - Mailing list pgsql-bugs

From david.thomas@enterprisedb.com
Subject BUG #7885: postmaster panic on startup does not release shared memory
Date
Msg-id E1U6Q65-0007P8-Lp@wrigleys.postgresql.org
Whole thread Raw
Responses Re: BUG #7885: postmaster panic on startup does not release shared memory  (Bruce Momjian <bruce@momjian.us>)
List pgsql-bugs
The following bug has been logged on the website:

Bug reference:      7885
Logged by:          David Thomas
Email address:      david.thomas@enterprisedb.com
PostgreSQL version: 9.2.3
Operating system:   CentOS 6.3
Description:        =


It seems that if the postmaster encounters a PANIC condition during startup,
it leaves it's allocated shared memory segments around:

-bash-4.1$ ipcs -a

------ Shared Memory Segments --------
key        shmid      owner      perms      bytes      nattch     status

------ Semaphore Arrays --------
key        semid      owner      perms      nsems

------ Message Queues --------
key        msqid      owner      perms      used-bytes   messages

-bash-4.1$ /usr/pgsql-9.2/bin/postmaster --single -D
/var/lib/pgsql/9.2/data/ test
PANIC:  could not locate a valid checkpoint record
Aborted
-bash-4.1$ ipcs -a

------ Shared Memory Segments --------
key        shmid      owner      perms      bytes      nattch     status
0x00000001 753664     postgres   600        41279488   0

------ Semaphore Arrays --------
key        semid      owner      perms      nsems
0x00000001 5439490    postgres   600        17
0x00000002 5472259    postgres   600        17
0x00000003 5505028    postgres   600        17
0x00000004 5537797    postgres   600        17
0x00000005 5570566    postgres   600        17
0x00000006 5603335    postgres   600        17
0x00000007 5636104    postgres   600        17

------ Message Queues --------
key        msqid      owner      perms      used-bytes   messages

Considering that it was able to allocate this memory before the panic
occurred, it should remove them before exiting.

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