Re: Bgwriter behavior - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: Bgwriter behavior
Date
Msg-id 200412222103.iBML3LA22502@candle.pha.pa.us
Whole thread Raw
In response to Re: Bgwriter behavior  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Bgwriter behavior
List pgsql-hackers
Tom Lane wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > So what are we doing for 8.0?
> 
> Well, it looks like RC2 has already crashed and burned --- I can't
> imagine that Marc will let us release without an RC3 given what was
> committed today, never mind the btree bug that Mark Wong seems to have
> found.  So maybe we should just bite the bullet and do something real
> about this.
> 
> I'm willing to code up a proposed patch for the two-track idea I
> suggested, and if anyone else has a favorite maybe they could write
> something too.  But do we have the resources to test such patches and
> make a decision in the next few days?
> 
> At the moment my inclination is to sit on what we have.  I've not seen
> any indication that 8.0 is really worse than earlier releases; the most
> you could argue against it is that it's not as much better as we hoped.
> That's not grounds to muck around at the RC3 stage.

I remember the other difference between 8.0 and pre-8.0.  When a backend
has to write a block in 8.0, it does a write _plus_ fsync(), while in
pre-8.0 it did only a write.  There was a proposal to pass backend write
information to the background writer so it would know to fsync at
checkpoint, but it was decided that backend writing would be rare.  I
think we have to rethink that assumption.

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
359-1001+  If your life is a hard drive,     |  13 Roberts Road +  Christ can be your backup.        |  Newtown Square,
Pennsylvania19073
 


pgsql-hackers by date:

Previous
From: Tom Lane
Date:
Subject: Re: Can't Restart ver 8.0b3
Next
From: Rémi Zara
Date:
Subject: Regression (semi)fix for netbsd-mac68k