Re: Why reset pgstat during recovery - Mailing list pgsql-hackers

From Masahiro Ikeda
Subject Re: Why reset pgstat during recovery
Date
Msg-id 14AD7450-F1F9-47D0-B189-476C8798FD24@oss.nttdata.com
Whole thread Raw
In response to Why reset pgstat during recovery  ("蔡梦娟(玊于)" <mengjuan.cmj@alibaba-inc.com>)
List pgsql-hackers


On 2021/04/02 18:41, 蔡梦娟(玊于) wrote:
>
>  Hi, all
>
>  I want to know why call pgstat_reset_all function during recovery
> process,  under what circumstances the data will be invalid after recovery?

If my understanding is right, PITR is the case. Now, the stats files are
generated as a one-time snapshot. This means that the stats counters
saved at last may not be valid for the specific point in time.

FWIW, there was a related discussion([1]) although the behavior is not
changed yet.

[1] https://www.postgresql.org/message-id/1416.1479760254%40sss.pgh.pa.us

Regards,
--
Masahiro Ikeda
NTT DATA CORPORATION




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