Re: Logging WAL when updating hintbit

On 19 November 2013 22:19, Sawada Masahiko Wrote

> >>
> >> Thank you for comment.
> >> Actually, I had thought to add separate parameter.
> >
> > I think that he said that if you can proof that amount of WAL is
> > almost same and without less performance same as before, you might
> not
> > need to separate parameter in your patch.
> >
>
> Thanks!
> I took it wrong.
> I think that there are quite a few difference amount of WAL.
>
> > Did you test about amount of WAL size in your patch?
>
> Not yet. I will do that.

1. Patch applies cleanly to master HEAD.
2. No Compilation Warning.
3. It works as per the patch expectation.

Some Suggestion:
1. Add new WAL level ("all") in comment in postgresql.conf
wal_level = hot_standby # minimal, archive, or hot_standby

Performance Test Result:
Run with pgbench for 300 seconds

WAL level : hot_standby
WAL Size : 111BF8A8
TPS : 125

WAL level : all
WAL Size : 11DB5AF8
TPS : 122

* TPS is almost constant but WAL size is increased around 11M.

This is the first level of observation, I will continue to test few more scenarios including performance test on standby.

Regards,
Dilip Kumar