Re: Enabling Checksums

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>
To: Greg Smith <greg@2ndquadrant.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Andres Freund <andres@2ndquadrant.com>, Ants Aasma <ants@cybertec.at>, Heikki Linnakangas <hlinnakangas@vmware.com>, Jeff Davis <pgsql@j-davis.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2013-03-18T14:01:24Z
Lists: pgsql-hackers
On 18 March 2013 00:50, Greg Smith <greg@2ndquadrant.com> wrote:
> On 3/17/13 1:41 PM, Simon Riggs wrote:
>>
>> So I'm now moving towards commit using a CRC algorithm. I'll put in a
>> feature to allow algorithm be selected at initdb time, though that is
>> mainly a convenience  to allow us to more easily do further testing on
>> speedups and whether there are any platform specific regressions
>> there.
>
> That sounds reasonable.  As I just posted, I'm hoping Ants can help make a
> pass over a CRC16 version, since his one on the Fletcher one seemed very
> productive.  If you're spending time looking at this, I know I'd prefer to
> see you poking at the WAL related aspects instead.  There are more of us who
> are capable of crunching CRC code than the list of people who have practice
> at WAL changes like you do.

Just committed the first part, which was necessary refactoring.

I see at least 2 further commits here:

* Next part is the checksum patch itself, with some checksum calc or
other (mostly unimportant from a code perspective, since the actual
algorithm is just a small isolated piece of code.

* Further commit(s) to set the agreed checksum algorithm and/or tune it.

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