Re: Bgwriter behavior

John Hansen wrote:
> > I ran some tests last week and can report results similar on Tom's test:
> > 
> >     pgbench -i -s 10 bench
> >     pgbench -c 10 -t 10000 bench
> > 
> > The tests were on a machine with a single SCSI drive that doesn't lie
> > about fsync.  I found 7.4.X got around 75tps while 8.0 got 100tps, very
> > similar to the 65/107 numbers Tom had.
> 
> You do realize, that pgbench result comparisons are about as useful as a
> fork for eating soup?


> 
> On another note, how do you know for sure, that your drive does not lie
> about fsync?

> 
> Did you run the tests with fsync turned off vs fsync on?

I just tried and got 115tps with fsync off vs 100 with fsync on, so
fsync is certainly doing something.

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