Re: Checkpoint Tuning Question

> So this thought leads to a couple of other things Dan could test.
> First, see if turning off full_page_writes makes the hiccup go away.
> If so, we know the problem is in this area (though still not exactly
> which reason); if not we need another idea.  That's not a good permanent
> fix though, since it reduces crash safety.  The other knobs to
> experiment with are synchronous_commit and wal_sync_method.  If the
> stalls are due to commits waiting for additional xlog to get written,
> then async commit should stop them.  I'm not sure if changing
> wal_sync_method can help, but it'd be worth experimenting with.
>
>                        regards, tom lane
>

All of my testing to date has been done with synchronous_commit=off

I just tried setting full_page_writes=off - and like magic, the entire
hiccup went away.

Thanks,

Dan