Re: Defaulting wal_sync_method to fdatasync on Linux for 9.1?

On Tue, Nov 16, 2010 at 3:39 PM, Greg Smith <greg(at)2ndquadrant(dot)com> wrote:
> I want to next go through and replicate some of the actual database level
> tests before giving a full opinion on whether this data proves it's worth
> changing the wal_sync_method detection.  So far I'm torn between whether
> that's the right approach, or if we should just increase the default value
> for wal_buffers to something more reasonable.

How about both?

open_datasync seems problematic for a number of reasons - you get an
immediate write-through whether you need it or not, including, as you
point out, the case where the you want to write several blocks at once
and then force them all out together.

And 64kB for a ring buffer just seems awfully small.

--
Robert Haas
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