On Wed, Oct 1, 2008 at 11:36 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> 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.
That's debatable and would be dependent on cache and the workload.
In our case however, because shared buffers doesn't scale, we would
end up doing a lot more block-level checksums than the other vendors
just pushing the block to/from the OS cache.
--
Jonah H. Harris, Senior DBA
myYearbook.com
