On 2018-05-01 13:43:14 -0400, Robert Haas wrote:
> On Tue, May 1, 2018 at 1:41 PM, Andres Freund wrote:
> > I unfortunately don't have access to the relevant reports anymore, so
> > it's only by memory. What I do remember is that a few I saw
> > pg_stat_bgwriter.buffers_backend_fsync values that w
On Tue, May 1, 2018 at 1:41 PM, Andres Freund wrote:
> I unfortunately don't have access to the relevant reports anymore, so
> it's only by memory. What I do remember is that a few I saw
> pg_stat_bgwriter.buffers_backend_fsync values that we a pretty sizable
> fraction of the buffers written by b
On 2018-05-01 13:21:21 -0400, Robert Haas wrote:
> On Mon, Apr 30, 2018 at 7:08 PM, Andres Freund wrote:
> >> True, but has anyone ever actually observed a non-zero
> >> pg_stat_bgwriter.buffers_backend_fsync in the wild after the
> >> compaction queue stuff was added/backpatched?
> >
> > Yes.
>
On Mon, Apr 30, 2018 at 7:08 PM, Andres Freund wrote:
>> True, but has anyone ever actually observed a non-zero
>> pg_stat_bgwriter.buffers_backend_fsync in the wild after the
>> compaction queue stuff was added/backpatched?
>
> Yes.
Care to elaborate?
--
Robert Haas
EnterpriseDB: http://www.en
On 2018-04-30 16:07:48 -0700, Peter Geoghegan wrote:
> On Mon, Apr 30, 2018 at 4:03 PM, Andres Freund wrote:
> >> Is this a problem in practice, though? I don't remember seeing any reports
> >> of the fsync queue filling up, after we got the code to compact it. I don't
> >> know if anyone has been
On Mon, Apr 30, 2018 at 4:03 PM, Andres Freund wrote:
>> Is this a problem in practice, though? I don't remember seeing any reports
>> of the fsync queue filling up, after we got the code to compact it. I don't
>> know if anyone has been looking for that, so that might also explain the
>> absence
On 2018-04-25 09:19:52 +0300, Heikki Linnakangas wrote:
> On 24/04/18 21:00, Andres Freund wrote:
> > Right now if the queue is full and can't be compacted we end up
> > fsync()ing on every single write, rather than once per checkpoint
> > afaict. That's a fairly horrible.
> >
> > For the case tha
On 24/04/18 21:00, Andres Freund wrote:
Right now if the queue is full and can't be compacted we end up
fsync()ing on every single write, rather than once per checkpoint
afaict. That's a fairly horrible.
For the case that there's no space in the map, I'd suggest to just do
10% or so of the fsync
