Re: Moving more work outside WALInsertLock

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Jeff Janes <jeff.janes@gmail.com>
Cc: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2011-12-15T16:48:47Z
Lists: pgsql-hackers
Jeff Janes <jeff.janes@gmail.com> writes:
> On Thu, Dec 15, 2011 at 7:34 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> This patch may or may not be useful, but this description of it is utter
>> nonsense, because we already do compute that before taking the lock.
>> Please try again to explain what you're doing?

> Currently the CRC of all the data minus the header is computed outside the lock,
> but then the header's computation is added and the CRC is finalized
> inside the lock.

Quite.  AFAICS that is not optional, unless you are proposing to remove
the prev_link from the scope of the CRC, which is not exactly a
penalty-free change.

			regards, tom lane