Re: RC2 and open issues

Greg Stark wrote:
>
> Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> writes:
>
> > Maybe we need a hybrid approach: clean a few percent of the LRU end of
> > the ARC list in order to keep backends from blocking on writes, plus run
> > a clock scan to keep checkpoints from having to do much.
>
> Well if you just keep note of when the last clock scan started then when you
> get to the end of the list you've _done_ a checkpoint.
>
> Put another way, we already have such a clock scan, it's called checkpoint.
> You could have checkpoint delay between each page write long enough to spread
> the checkpoint i/o out over a configurable amount of time -- say half the
> checkpoint interval -- and be done with that side of things.

But don't you have to keep the WAL files around longer then.

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