Re: Handing off SLRU fsyncs to the checkpointer

On 2020-Aug-25, Andres Freund wrote:

> Hi,
> 
> On 2020-08-26 15:58:14 +1200, Thomas Munro wrote:
> > >                 --12.51%--compactify_tuples
> > >                           PageRepairFragmentation
> > >                           heap2_redo
> > >                           StartupXLOG
> > 
> > I wonder if there is something higher level that could be done to
> > reduce the amount of compaction work required in the first place, but
> > in the meantime I'm very happy if we can improve the situation so much
> > with such a microscopic improvement that might eventually benefit
> > other sorting stuff...
> 
> Another approach could be to not perform any sorting during recovery,
> instead including enough information in the WAL record to avoid doing a
> full blown PageRepairFragmentation during recovery.

Hmm, including the sorted ItemId array in the WAL record might make
sense to alleviate the qsort work ...

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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