Skip site navigation (1) Skip section navigation (2)

Re: Block-level CRC checks

From: Alvaro Herrera <alvherre(at)commandprompt(dot)com>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: "Jonah H(dot) Harris" <jonah(dot)harris(at)gmail(dot)com>, pgsql(at)mohawksoft(dot)com, Hannu Krosing <hannu(at)2ndquadrant(dot)com>, Decibel! <decibel(at)decibel(dot)org>, Pg Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: Block-level CRC checks
Date: 2008-10-01 15:57:31
Message-ID: 20081001155731.GE3878@alvh.no-ip.org (view raw or flat)
Thread:
Lists: pgsql-hackers
Tom Lane escribió:
> "Jonah H. Harris" <jonah(dot)harris(at)gmail(dot)com> writes:

> > I probably wouldn't compare checksumming *every* WAL record to a
> > single block-level checksum.
> 
> No, not at all.  Block-level checksums would be an order of magnitude
> more expensive: they're on bigger chunks of data and they'd be done more
> often.

More often?  My intention is that they are checked when the buffer is
read in, and calculated/stored when the buffer is written out.
In-memory changers of the block do not check nor recalculate the sum.

Is this not OK?

-- 
Alvaro Herrera                                http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support

In response to

Responses

pgsql-hackers by date

Next:From: Gregory StarkDate: 2008-10-01 15:57:50
Subject: Re: Block-level CRC checks
Previous:From: Tom LaneDate: 2008-10-01 15:56:30
Subject: Re: Block-level CRC checks

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group