Re: Moving more work outside WALInsertLock

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>

To: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>

Cc: Tom Lane <tgl@sss.pgh.pa.us>, Jeff Janes <jeff.janes@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>

Date: 2011-12-16T12:37:33Z

Lists: pgsql-hackers

On Fri, Dec 16, 2011 at 12:07 PM, Heikki Linnakangas
<heikki.linnakangas@enterprisedb.com> wrote:

> Anyway, I'm looking at ways to make the memcpy() of the payload happen
> without the lock, in parallel, and once you do that the record header CRC
> calculation can be done in parallel, too. That makes it irrelevant from a
> performance point of view whether the prev-link is included in the CRC or
> not.

Better plan. So we keep the prev link in the CRC.

I already proposed a design for that using page-level share locks any
reason not to go with that?

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