Re: Postmaster.pid - what do the various lines stand for? - Mailing list pgsql-novice

From Tom Lane
Subject Re: Postmaster.pid - what do the various lines stand for?
Date
Msg-id 8720.1430950389@sss.pgh.pa.us
Whole thread Raw
In response to Re: Postmaster.pid - what do the various lines stand for?  (Paul Linehan <linehanp@tcd.ie>)
List pgsql-novice
Paul Linehan <linehanp@tcd.ie> writes:
> I'm just not sure what this part means
> *      7   shared memory key (not present on Windows)
> This corresponds to the line  " 5432001   2195471"

> I did Google "PostgreSQL shared key" and couldn't find
> anything significant - why are there two numbers?

It's just the way the SysV shared memory API works --- there's a "key"
chosen by the application, and an "identifier" which is chosen by the
kernel, but they're both just identifiers for a particular shared memory
segment.  "man 2 shmget" might be informative, or try "sudo ipcs -m"
for a listing of SysV shared memory segments on your system.

            regards, tom lane


pgsql-novice by date:

Previous
From: Paul Linehan
Date:
Subject: Re: Postmaster.pid - what do the various lines stand for?
Next
From: Bruce Momjian
Date:
Subject: Re: Why is Hash index not transaction safe.