Re: Block-level CRC checks - Mailing list pgsql-hackers

From Alvaro Herrera
Subject Re: Block-level CRC checks
Date
Msg-id 20081001155731.GE3878@alvh.no-ip.org
Whole thread Raw
In response to Re: Block-level CRC checks  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Block-level CRC checks
Re: Block-level CRC checks
Re: Block-level CRC checks
List pgsql-hackers
Tom Lane escribió:
> "Jonah H. Harris" <jonah.harris@gmail.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


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