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Date: Tue, 27 Sep 2011 11:42:48 +0200
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Subject: Re: scalabitily of the _changes feed
From: Benoit Chesneau <bchesneau@gmail.com>
To: user@couchdb.apache.org
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On Tue, Sep 27, 2011 at 11:40 AM, Dominic Tarr <dominic.tarr@gmail.com> wro=
te:
> is it okay to register a huge number of listeners to the changes feed?
>

It will open one socket / feed. So it depends on your os limits
mostly. You will have to tune the backlog & fd limit for a start.


> I notice that you can use a filter function, which gets passed the reques=
t
> parameters,
> does this mean that the filter function will be called for each doc, for
> each listener on the changes feed?

Yes

> or are the results of each filter call cached so that it is possible to
> efficiently register many listeners using the same filter function?

It isn't cached in couch, but you can cache it on your applications.

- beno=EEt