Re: Load Distributed Checkpoints, final patch

Gregory Stark wrote:
> "Heikki Linnakangas" <heikki(at)enterprisedb(dot)com> writes:
>
>> We could just allow any value up to 1.0, and note in the docs that you should
>> leave some headroom, unless you don't mind starting the next checkpoint a bit
>> late. That actually sounds pretty good.
>
> What exactly happens if a checkpoint takes so long that the next checkpoint
> starts. Aside from it not actually helping is there much reason to avoid this
> situation?

Not really. We might run out of preallocated WAL segments, and will have
to create more. Recovery could be longer than expected since the real
checkpoint interval ends up being longer, but you can't make very
accurate recovery time estimations anyway.

> Have we ever actually tested it?

I haven't.

--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com