On 2015-06-26 14:48:35 -0300, Alvaro Herrera wrote: > Andres Freund wrote: > > > Rework the way multixact truncations work. > > I spent some time this morning reviewing this patch and had some > comments that I relayed over IM to Andres.
Thanks for that! > 2. We set PGXACT->delayChkpt while the truncation is executed. This > seems reasonable, and there's a good reason for it, but all the other > users of this facility only do small operations with this thing grabbed, > while the multixact truncation could take a long time because a large > number of files might be deleted. Maybe it's not a problem to have > checkpoints be delayed by several seconds, or who knows maybe even a > minute in a busy system. (We will have checkpointer sleeping in 10ms > intervals until the truncation is complete). I don't think this is a problem. Consider that we're doing all this in the checkpointer today, blocking much more than just the actual xlog insertion. That's a bigger problem, as we'll not do the paced writing during that and such. The worst thatthis can cause is a bunch of sleeps, that seems fairly harmless. Greetings, Andres Freund -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
