Shared Memory explanation/little bug? - Mailing list pgsql-admin

Hello admins

To days ago I saw that one of my database clusters crashed. I was
looking into the log file and found the following:

2003-12-17 17:42:19 FATAL:  pre-existing shared memory block (key
5432001, ID 797966336) is still in use
HINT:  If you're sure there are no old server processes still running,
remove the shared memory block with the command "ipcrm", or just delete
the file "/u00/app/pgsql/admin/CLUSTER2/postmaster.pid".

Because I am courious I wanted to know a little more about shared
memories. And I was looking for the problem. I did not find the problem
causing block (see below, probably it was already removed) but two
things were remarkable:

1.) ipcs shows the keys in hex but the alert log in dec:
key 5432001 --> 0x0052E2C1

2.) The ID looked a little strange:
797966336 --> 0x2F900000 (0x2F90 = 12176)

Before I post an enhancment request/bug I would like to know you opinion:

1.) Would it be worth to have the output in hex (also).
2.) Is item 2 a bug or did I not understand something?

Thanks for feedback
Oli

------------------------------------------------------------

postgres@master:/u00/app/pgsql - rdbms740/template0> ipcs

------ Shared Memory Segments --------
key        shmid      owner      perms      bytes      nattch     status
0x0052e6a9 262144     postgres  600        10436608   1
0x0052fa31 294913     postgres  600        10436608   1
0x0052f649 327682     postgres  600        1466368    1
0x0052ee79 360451     postgres  600        1466368    3
0x0052f261 393220     postgres  600        1466368    3

------ Semaphore Arrays --------
key        semid      owner      perms      nsems
0x0052e6a9 0          postgres  600        17
0x0052e6aa 32769      postgres  600        17
0x0052e6ab 65538      postgres  600        17
0x0052e6ac 98307      postgres  600        17
0x0052e6ad 131076     postgres  600        17
0x0052e6ae 163845     postgres  600        17
0x0052e6af 196614     postgres  600        17
0x0052fa31 229383     postgres  600        17
0x0052fa32 262152     postgres  600        17
0x0052fa33 294921     postgres  600        17
0x0052fa34 327690     postgres  600        17
0x0052fa35 360459     postgres  600        17
0x0052fa36 393228     postgres  600        17
0x0052fa37 425997     postgres  600        17
0x0052f649 458766     postgres  600        17
0x0052f64a 491535     postgres  600        17
0x0052f64b 524304     postgres  600        17
0x0052ee79 557073     postgres  600        17
0x0052ee7a 589842     postgres  600        17
0x0052ee7b 622611     postgres  600        17
0x0052f261 655380     postgres  600        17
0x0052f262 688149     postgres  600        17
0x0052f263 720918     postgres  600        17

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

-------------------------------------------------------

Oli Sennhauser
Database-Engineer (Oracle & PostgreSQL)
Rebenweg 6
CH - 8610 Uster / Switzerland

Phone (+41) 1 940 24 82 or Mobile (+41) 79 450 49 14
e-Mail oli.sennhauser@bluewin.ch
Website http://mypage.bluewin.ch/shinguz/PostgreSQL/

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