RE: Protect syscache from bloating with negative cache entries

From: "Tsunakawa, Takayuki" <tsunakawa(dot)takay(at)jp(dot)fujitsu(dot)com>
To: 'Kyotaro HORIGUCHI' <horiguchi(dot)kyotaro(at)lab(dot)ntt(dot)co(dot)jp>, "GavinFlower(at)archidevsys(dot)co(dot)nz" <GavinFlower(at)archidevsys(dot)co(dot)nz>
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Subject: RE: Protect syscache from bloating with negative cache entries
Date: 2019-01-21 07:12:41
Message-ID: 0A3221C70F24FB45833433255569204D1FB6C78A@G01JPEXMBYT05
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From: Kyotaro HORIGUCHI [mailto:horiguchi(dot)kyotaro(at)lab(dot)ntt(dot)co(dot)jp]
> 0003: Remote GUC setting
>
> It is independent from the above two, and heavily arguable.
>
> pg_set_backend_config(pid, name, value) changes the GUC <name> on the
> backend with <pid> to <value>.
>

Not having looked at the code yet, why did you think this is necessary? Can't we always collect the cache stats? Is it heavy due to some locking in the shared memory, or sending the stats to the stats collector?

Regards
Takayuki Tsunakawa

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