Thread: VACUUM query

VACUUM query

From
"news.apexsc.com"
Date:
System: Linux 6.2; Postgresql 7.1.3
Hi,

can anyone tell me how to:
1. safely abort a VACUUM once it has started?
2. safely abort a scheduled vacuumdb once it has started?

Thanks,

Lance



Re: VACUUM query

From
Tom Lane
Date:
"news.apexsc.com" <lance@companywatch.co.uk> writes:
> System: Linux 6.2; Postgresql 7.1.3
> can anyone tell me how to:
> 1. safely abort a VACUUM once it has started?
> 2. safely abort a scheduled vacuumdb once it has started?

In general, you cancel a VACUUM the same way as any other query:
control-C if interactively working in psql, or PQrequestCancel()
in a custom application, or send SIGINT to the individual backend
if you are an admin watching something go nuts.

In 7.1.* there is a known bug that aborting VACUUM partway through
vacuuming a TOAST table may leave things in a bad state.  (Actually
there is nothing wrong with the table, but the TOAST code will get
confused because it doesn't check tuple status correctly.  Re-vacuuming
will fix it, if you chance to get bit.)  So I don't really recommend
doing this on a routine basis, until you update to 7.2.

            regards, tom lane