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From: Jan Ceuleers <jan.ceuleers@computer.org>
To: linux-kernel@vger.kernel.org
Subject: Reading entropy_avail file appears to consume entropy
Date: Fri, 19 Mar 2010 19:12:43 +0100	[thread overview]
Message-ID: <4BA3BE9B.5050201@computer.org> (raw)

I'm using the 2.6.31 kernel that comes with Ubuntu 9.10.

If I

   # watch cat /proc/sys/kernel/random/entropy_avail

then the size of the entropy pool falls rapidly (by more than 200 bytes per 2s interval). It settles down around 160 bytes.

The machines on which I've done the above experiment are otherwise idle. They are also dramatically different from one another: one is a laptop, the other is an embedded device (a Soekris net5501).

Is this supposed to happen?

Thanks, Jan

             reply	other threads:[~2010-03-19 18:15 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-03-19 18:12 Jan Ceuleers [this message]
     [not found] <epOXE-4EU-7@gated-at.bofh.it>
     [not found] ` <b7822cd7-97f3-489e-a16b-686b0419d3f2@k19g2000yqn.googlegroups.com>
2010-04-05  7:50   ` Reading entropy_avail file appears to consume entropy Jan Ceuleers
2010-04-05  9:30     ` Eric Dumazet

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