Re: What to do when dynamic shared memory control segment is corrupt

[Sherrylyn Branchaw <sbranchaw@xxxxxxxxx>]

Yeah, I'd like to know that too.  The complaint about corrupt shared
memory may be just an unrelated red herring, or it might be a separate
effect of whatever the primary failure was ... but I think it was likely
not the direct cause of the failure-to-restart.

Anyway, I would not be afraid to try restarting the postmaster manually
if it died.  Maybe don't do that repeatedly without human intervention;
but PG is pretty robust against crashes.  We developers crash it all the
time, and we don't lose data.

Understood, and thanks. I was basing my concern on a message in the mailing lists that suggested that postgres might fail to start up in the event of a corrupted memory segment. I would link to the message directly, but I keep getting backend server error messages when I try to search for it today. At any rate, it looked there was a chance that it was a deliberate design choice, and I didn't want to ignore it if so. It's good to know that this is not the case.

I realize that you're most focused on less-downtime, but from my
perspective it'd be good to worry about collecting evidence as to
what happened exactly.  

Absolutely. I would love to know why this is happening too. However, our priorities have been set in part by a very tight deadline handed down from the C-levels to migrate to Aurora, so we have to focus our energies accordingly. I will be back with core files if this happens again before we're completely migrated over. Meanwhile, thank you for assuring me we have no current data corruption and that it's safe to restart next time without taking additional action to avoid or detect corruption.

Best,

Sherrylyn