Re: [PATCHES] WAL: O_DIRECT and multipage-writer (+

On Tue, 2005-03-01 at 13:53 -0800, Mark Wong wrote:
> On Thu, Feb 03, 2005 at 07:25:55PM +0900, ITAGAKI Takahiro wrote:
> > Hello everyone.
> >
> > I fixed two bugs in the patch that I sent before.
> > Check and test new one, please.
>
> Ok, finally got back into the office and was able to run 1 set of
> tests.
>
> So the new baseline result with 8.0.1:
> http://www.osdl.org/projects/dbt2dev/results/dev4-010/309/
> Throughput: 3639.97
>
> Results with the patch but open_direct not set:
> http://www.osdl.org/projects/dbt2dev/results/dev4-010/308/
> Throughput: 3494.72
>
> Results with the patch and open_direct set:
> http://www.osdl.org/projects/dbt2dev/results/dev4-010/312/
> Throughput: 3489.69
>
> You can verify that the wall_sync_method is set to open_direct under
> the "database parameters" link, but I'm wondering if I missed
> something. It looks a little odd the the performance dropped.

Is there anything more to say on this?
Is it case-closed, or is there further work underway - I can't see any
further chat on this thread.

These results show it doesn't work better on larger systems. The
original testing showed it worked better on smaller systems - is there
still scope to include this for smaller configs?

If not, thanks for taking the time to write the patch and investigate
whether changes in this area would help. Not every performance patch
improves things, but that doesn't mean we shouldn't try...

Best Regards, Simon Riggs