On Sun, Apr 21, 2019 at 10:21 PM Michael Paquier <michael@paquier.xyz> wrote:
> If you create the extra file when a segment is finished and we switch
> to a new one, then the extra work would happen for a random backend,
> and it is going to be more costly to scan a 1GB segment than a 16MB
> segment as a one-time operation, and less backends would see a
> slowdown at equal WAL data generated. From what I can see, you are
> not planning to do such operations when a segment finishes being
> written, which would be much better.
Well, my plan was to do it all from a background worker, so I do not
think a random backend would ever have to do any extra work.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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