Re: [Exim] No locking problem for hints databases

> Of the 5000 messages, how many were delivered first time? Specifically,
> we were talking about situations where a very small percentage (less
> than 15%? Maybe less than 5%) could be delivered first time.

They were all delivered first time, but Exim still locks access to
various DBs for each message. As I said, I was looking at it for local
delivery only, because that's where my largest bottleneck that's worth
optimising is. I have different machines for local and remote delivery,
but remote always ran fine without trouble.

That's quite different from your setup, but since I raised the question if
avoiding the hints might speed up local delivery, I thought I should also
try to answer that, as it might save Philip some work that has no effect.

If you can not deliver most messages on first try, how about not trying
direct deliveries and leaving that to queue runners?

> At the same time, were there new messages coming in to the queue?

Yes, but not many. Check src/dbfn.c and grep for F_SETLKW to find where
the DBs are locked. It is easy to add some additional code there. I
also suggest to use tmpfs for the DBs. It takes 30 MB on my outgoing
servers, and much less everywhere else.

Michael