Re: Separating bgwriter and checkpointer

2011/10/19 Fujii Masao <masao(dot)fujii(at)gmail(dot)com>:
> On Tue, Oct 18, 2011 at 10:18 PM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
>> Any reason or objection to committing this patch?
>
> The checkpointer doesn't call pgstat_send_bgwriter(), but it should.
> Otherwise, some entries in pg_stat_bgwriter will never be updated.

Yes, checkpoints_req, checkpoints_timed and buffer_checkpoint are not
being updated with this patch.

> If we adopt the patch, checkpoint is performed by checkpointer. So
> it looks odd that information related to checkpoint exist in
> pg_stat_bgwriter. We should move them to new catalog even if
> it breaks the compatibility?

Splitting pg_stat_bgwriter into pg_stat_bgwriter and
pg_stat_checkpointer will break something internal?

With this modification we'll see applications like monitoring tools
breaking, but they could use a view to put data back together in a
compatible way, IMHO.

--
Dickson S. Guedes
mail/xmpp: guedes(at)guedesoft(dot)net - skype: guediz
http://guedesoft.net - http://www.postgresql.org.br