Re: Standby trying "restore_command" before local WAL - Mailing list pgsql-hackers

From Stephen Frost
Subject Re: Standby trying "restore_command" before local WAL
Date
Msg-id 20180808161551.GL27724@tamriel.snowman.net
Whole thread Raw
In response to Re: Standby trying "restore_command" before local WAL  (David Steele <david@pgmasters.net>)
List pgsql-hackers
Greetings,

* David Steele (david@pgmasters.net) wrote:
> I can see cases where it *might* be worth it, but several backup tools
> support prefetch and/or parallelism which should be able to keep
> Postgres fed with WAL unless there is very high latency to the repo.
> I'm not sure the small performance boost (if any) would be enough to
> justify the extra code paths and tests.

...

> That said, if there is anything we can do in core to make these tools
> simpler or more performant I'm all for it.  For instance, it might be
> good to have return code (as suggested upstream) that indicates to
> Postgres that the segment in pg_wal is a good choice.   Some use cases
> might benefit enormously even if it doesn't make sense as a general case.

Well, if there are some use cases that would benefit greatly from it
then it may just be worth it.  That said, it doesn't sound like a common
enough ask to be something we'd prioritize for pgbackrest, at least not
without actual client demand/interest in it.  If someone else wants to
write the tests and the code and contribute that capability, we'd
certainly welcome it.

Thanks!

Stephen

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