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From Brian Candler <>
Subject Re: CouchDB for production
Date Tue, 18 Aug 2009 08:52:27 GMT
On Tue, Aug 18, 2009 at 08:52:17AM +0100, [mRg] wrote:
> ? As an idea of scale the site is expected to handle 8,000,000 hits per
> month (approx 250,000 per day) and while Couch isnt providing all of the
> site functionality it is supporting the tagging elements which is a major
> part of the site.

250,000 hits per day is an average of less than 3 hits per second. You could
probably run it on a netbook :-)

However you should consider how many updates and view updates are taking
place, and include this in your load-testing.

That is: if this is all just read activity, it will be handled efficiently
by the btree indexes, especially if you have enough RAM for these to remain

But if there are lots of updates taking place, then there will be lots of
view-building activity going on too. The worst-case scenario here is if you
have lots of DBs (e.g. one DB per user); lots of updates occur to a user's
DB while they are away; and then they come back and hit a view. This will
cause all the views in that design doc to be updated from some point in the
past until now, which would cause a large disk and CPU spike which could
cause performance degradation for other users.

In my experience, this is one aspect which Linux doesn't handle well: do
something which involves lots of disk writes (even just a big cp or tar) and
interactive performance for the rest of the system suffers badly. Back when
I was using FreeBSD in production it seemed to be better in that regard, but
I'm not sure if that's still true today.



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