Re: FSM rewrite committed, loose ends

Heikki Linnakangas napsal(a):
> Zdenek Kotala wrote:
>> Heikki Linnakangas napsal(a):
>>> The FSM is not updated during WAL replay. That means that after crash
>>> recovery, the FSM won't be completely up-to-date, but at roughly the
>>> state it was at last checkpoint. In a warm stand-by, the FSM will
>>> reflect the situation at last full backup. We need to think when the
>>> FSM should be updated during WAL replay. Probably not after every
>>> record, because of the overhead, but certainly more often than never.
>>
>> What's about after a page write during a WAL replay?
>
> You mean when a page is evicted from the buffer cache?

Yes

> That might be
> pretty good from performance point of view, but from a modularity point
> of view, the buffer manager should have no business modifying the FSM.

Yeah, it is true. I suggest to try modify FMS info on each manipulation
in WAL replay and if it will have performance issue we can start think
about improvements.

Zdenek