Horton

Re: 16-bit page checksums for 9.2

Robert Haas <robertmhaas@gmail.com>

View thread
From: Robert Haas <robertmhaas@gmail.com>
To: Simon Riggs <simon@2ndquadrant.com>
Cc: Andres Freund <andres@anarazel.de>, Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>, Kevin Grittner <Kevin.Grittner@wicourts.gov>, david@fetter.org, aidan@highrise.ca, stark@mit.edu, pgsql-hackers@postgresql.org
Date: 2012-01-06T21:44:02Z
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 Fri, Jan 6, 2012 at 3:47 PM, Simon Riggs <simon@2ndquadrant.com> wrote:
> Since we ignore hints during HS anyway,

No, we don't.  We need to ignore visibility map bits, but we need not
and do not ignore HEAP_XMIN_COMMITTED, HEAP_XMAX_COMMITTED, etc.

> not setting them seems OK if
> checksums defined. Or we can recommend that you don't use checksums on
> a standby. Whichever fits.
>
> Writing pages during recovery doesn't need WAL. If we crash, we replay
> using the already generated WAL.

Which is all fine, except when you start making changes that are not
WAL-logged.  Then, you have the same torn page problem that exists
when you it in normal running.

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