Re: snapshot too old issues, first around wraparound and then more. - Mailing list pgsql-hackers

From Peter Geoghegan
Subject Re: snapshot too old issues, first around wraparound and then more.
Date
Msg-id CAH2-Wzm0PgxD-MxMgK0gmg7Wf46H=akuvQ9oymOAEHn2sY1evA@mail.gmail.com
Whole thread Raw
In response to Re: snapshot too old issues, first around wraparound and then more.  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: snapshot too old issues, first around wraparound and then more.  (Peter Geoghegan <pg@bowt.ie>)
List pgsql-hackers
On Wed, Apr 1, 2020 at 1:25 PM Robert Haas <robertmhaas@gmail.com> wrote:
> Maybe that contrib module could even have some functions to simulate
> aging without the passage of any real time. Like, say you have a
> function or procedure old_snapshot_pretend_time_has_passed(integer),
> and it moves oldSnapshotControl->head_timestamp backwards by that
> amount. Maybe that would require updating some other fields in
> oldSnapshotControl too but it doesn't seem like we'd need to do a
> whole lot.

I like that idea. I think that I've spotted what may be an independent
bug, but I have to wait around for a minute or two to reproduce it
each time. Makes it hard to get to a minimal test case.

-- 
Peter Geoghegan



pgsql-hackers by date:

Previous
From: Alvaro Herrera
Date:
Subject: Re: Proposal: Expose oldest xmin as SQL function for monitoring
Next
From: Peter Geoghegan
Date:
Subject: Re: snapshot too old issues, first around wraparound and then more.