Re: Online enabling of checksums

Hi,

On Wed, Feb 21, 2018 at 09:53:31PM +0100, Magnus Hagander wrote:
> We’ve also included a small commandline tool, bin/pg_verify_checksums,
> that can be run against an offline cluster to validate all checksums.

The way it is coded in the patch will make pg_verify_checksums fail for
heap files with multiple segments, i.e. tables over 1 GB, becuase the
block number is consecutive and you start over from 0:

$ pgbench -i -s 80 -h /tmp
[...]
$ pg_verify_checksums -D data1
pg_verify_checksums: data1/base/12364/16396.1, block 0, invalid checksum
in file 6D61, calculated 6D5F
pg_verify_checksums: data1/base/12364/16396.1, block 1, invalid checksum
in file 7BE5, calculated 7BE7
[...]
Checksum scan completed
Data checksum version: 1
Files scanned:  943
Blocks scanned: 155925
Bad checksums:  76
 

Michael

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