Re: Postmaster.pid - what do the various lines stand for?

Paul Linehan <linehanp(at)tcd(dot)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