Re: BUG #9161: wal_writer_delay is limited to 10s

On 2014-02-17 14:24:09 -0800, Jeff Janes wrote:
> On Mon, Feb 17, 2014 at 1:53 PM, Andres Freund <andres(at)2ndquadrant(dot)com>wrote:
>
> > On 2014-02-17 13:48:34 -0800, Jeff Janes wrote:
> > > That only happens if an 8 KB boundary has been crossed. Depending on how
> > > big the records are that he is inserting, you can fit a lot of them in 8
> > > KB. If the records are small, or the table us unlogged so only commit
> > > messages get logged, then you could go many multiples of 10s without
> > > triggering a wake up due to crossing an 8 KB boundary.
> >
> > Unless I miss something we wake it up if *either* a 8kb boundary has
> > been crossed *or* if the async lsn hasn't been flushed yet.
> >
>
> I think it is either a 8kb boundary crossed, or the wal_writer is in "deep"
> sleep (i.e. 25 times the ordinary sleep).

Ick. Yes, I forgot that sleeping was defined that way (which is a bad
idea for the majority of cases imo).

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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