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From: "Grauel, Moritz" <grauel@adesso.de>
To: "user@couchdb.apache.org" <user@couchdb.apache.org>
Date: Tue, 29 Mar 2011 15:26:52 +0200
Subject: Surprisingly high CPU load
Thread-Topic: Surprisingly high CPU load
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Hi,

I am currently evaluating CouchDB. During my tests I have observed  suprisi=
ngly high CPU load. I have installed a fresh CouchDB 1.0.2, created a DB an=
d inserted one doc { 'hello':'world'}.

Then I just fetch this single document as often as possible. My expectation=
s are, that the network should be the bottleneck in this simple case.

However the CPU Load of couchdb is very high. with 5 concurrect threads fet=
ching the document I get around 90% cpu usage. Serving the json as a static=
 file with an apache yields about twice as many requests as couchdb and onl=
y about 50% cpu load.

I have repeated this test on linux in a vm, linux directly on the metal and=
 osx and the results are more or less similar.

I am very aware of the fact, that my 'benchmarks' are very rough... however=
 I am concerned about the actual performance of couchdb when serving lots o=
f requests.

Why is CouchDB generating such a high load? Why isn't couch able to saturat=
e the network?

I have tried disabling compression and setting the loglevel to error with n=
o effect.

Regards,

Mo  =