Re: 16-bit page checksums for 9.2 - Mailing list pgsql-hackers

From Robert Haas
Subject Re: 16-bit page checksums for 9.2
Date
Msg-id CA+TgmobVny0M5GYUvbs3Kj0BH_BZrwdEFCZJivEkVJm9q5YHaA@mail.gmail.com
Whole thread Raw
In response to Re: 16-bit page checksums for 9.2  ("Kevin Grittner" <Kevin.Grittner@wicourts.gov>)
List pgsql-hackers
On Wed, Jan 4, 2012 at 3:51 PM, Kevin Grittner
<Kevin.Grittner@wicourts.gov> wrote:
>> If double writes aren't going to give us anything "for free",
>> maybe that's not the right place to be focusing our
>> efforts...
>
> I'm not sure why it's not enough that they improve performance over
> the alternative.  Making some other feature with obvious overhead
> "free" seems an odd requirement to hang on this.  (Maybe I'm
> misunderstanding you on that point?)

Well, this thread is nominally about checksums, but here we are
talking about double writes, so I thought we were connecting those
features in some way?

Certainly, life is easier if we can develop them completely separately
- but checksums really ought to come with some sort of solution to the
problem of a torn-page with hint bit changes, IMO, and I thought
that's why were thinking so hard about DW just now.

Maybe I'm confused.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company


pgsql-hackers by date:

Previous
From: Tom Lane
Date:
Subject: Re: [BUGS] BUG #6379: SQL Function Causes Back-end Crash
Next
From: Robert Haas
Date:
Subject: Re: Regarding Checkpoint Redo Record