Re: Undetected corruption of table files - Mailing list pgsql-general

From Tom Lane
Subject Re: Undetected corruption of table files
Date
Msg-id 617.1188227815@sss.pgh.pa.us
Whole thread Raw
In response to Re: Undetected corruption of table files  ("Albe Laurenz" <all@adv.magwien.gv.at>)
Responses Re: [HACKERS] Undetected corruption of table files  ("Jonah H. Harris" <jonah.harris@gmail.com>)
Re: Undetected corruption of table files  (Gregory Stark <stark@enterprisedb.com>)
List pgsql-general
"Albe Laurenz" <all@adv.magwien.gv.at> writes:
> Tom Lane wrote:
>>> Would it be an option to have a checksum somewhere in each
>>> data block that is verified upon read?

>> That's been proposed before and rejected before.  See the archives ...

> I searched for "checksum" and couldn't find it. Could someone
> give me a pointer? I'm not talking about WAL files here.

"CRC" maybe?  Also, make sure your search goes all the way back; I think
the prior discussions were around the same time WAL was initially put
in, and/or when we dropped the WAL CRC width from 64 to 32 bits.
The very measurable overhead of WAL CRCs are the main thing that's
discouraged us from having page CRCs.  (Well, that and the lack of
evidence that they'd actually gain anything.)

            regards, tom lane

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