Re: 16-bit page checksums for 9.2

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>
To: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
Cc: Noah Misch <noah@leadboat.com>, Robert Haas <robertmhaas@gmail.com>, Andres Freund <andres@anarazel.de>, Kevin Grittner <Kevin.Grittner@wicourts.gov>, david@fetter.org, aidan@highrise.ca, stark@mit.edu, pgsql-hackers@postgresql.org
Date: 2012-02-29T16:24:21Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Wakeup WALWriter as needed for asynchronous commit performance.

On Wed, Feb 29, 2012 at 3:46 PM, Heikki Linnakangas
<heikki.linnakangas@enterprisedb.com> wrote:

>> Are you saying you would accept the patch if we had this?

> I think I would still be uncomfortable with the hacks in the page header.

There are no "hacks". There are some carefully designed changes with
input from multiple people, including yourself, and it copes as
gracefully as it can with backwards compatibility requirements.

> Less so than in the current form - you wouldn't need a flag to indicate
> whether the page has a valid checksum or not, which would clean it up quite
> a bit - but still.

I agree this would remove the reliance on a bit in the page header and
so make it even more robust.

I'll add the 2 phase enabling feature, making it happen at database level.

-- 
 Simon Riggs                   http://www.2ndQuadrant.com/
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