From mboxrd@z Thu Jan  1 00:00:00 1970
From: Steve Grubb <sgrubb@redhat.com>
Subject: Re: Audit issue
Date: Thu, 8 Nov 2007 19:28:07 -0500
Message-ID: <200711081928.07954.sgrubb@redhat.com>
References: <200710301248.24261.sgrubb@redhat.com>
	<20071108145651.GC28304@devserv.devel.redhat.com>
	<200711080959.31328.sgrubb@redhat.com>
Mime-Version: 1.0
Content-Type: text/plain;
  charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Return-path: <linux-audit-bounces@redhat.com>
In-Reply-To: <200711080959.31328.sgrubb@redhat.com>
Content-Disposition: inline
List-Unsubscribe: <https://www.redhat.com/mailman/listinfo/linux-audit>,
	<mailto:linux-audit-request@redhat.com?subject=unsubscribe>
List-Archive: <https://www.redhat.com/archives/linux-audit>
List-Post: <mailto:linux-audit@redhat.com>
List-Help: <mailto:linux-audit-request@redhat.com?subject=help>
List-Subscribe: <https://www.redhat.com/mailman/listinfo/linux-audit>,
	<mailto:linux-audit-request@redhat.com?subject=subscribe>
Sender: linux-audit-bounces@redhat.com
Errors-To: linux-audit-bounces@redhat.com
To: linux-audit@redhat.com
List-Id: linux-audit@redhat.com

On Thursday 08 November 2007 09:59:30 Steve Grubb wrote:
> On Thursday 08 November 2007 09:56:51 Alexander Viro wrote:
> > Easy enough to test - boot with audit disabled, run benchmarks, enabl=
e
> > it, flush all caches (e.g. by memory pressure), rerun the benchmarks,
> > compare... =A0I don't think it will be serious problem, but if it wil=
l
> > we can always look for trickier solutions.
>
> OK. I'll try to build a kernel and check this out. Might have some resu=
lts
> later.

OK, had a chance to do testing. First, the patch works. It solves the pro=
blem=20
that was reported. Here's some performance numbers using the performance =
test=20
I have at http://people.redhat.com/sgrubb/files/lspp-perf.tar.gz

without patch boot with audit=3D0
audit disabled: 38.9
audit enabled:  42.3

without patch boot with audit=3D1
audit disabled: 41.4
audit enabled: 42.9

with patch boot with audit=3D0
audit disabled: 38.6
audit enabled: 43.8

with patch boot with audit=3D1
audit disabled: 44.2
audit enabled: 44.6


So, when audit is enabled at boot. There is virtually no performance=20
difference between enabled and not. The old way, we had a 4% performance=20
improvement when audit was disabled. Looking at the audit=3D0 case, there=
 is=20
about a 3.5% performance hit when audit is enabled with the new patch. Th=
e=20
old way, audit disabled was always significantly faster ~ %4. With the pa=
tch=20
its only about 1% faster.

-Steve