From mboxrd@z Thu Jan  1 00:00:00 1970
From: douglas.santos@polymtl.ca (Douglas Santos)
Date: Wed, 17 Nov 2010 16:31:38 -0500
Subject: [ltt-dev] Benchmarks of kernel tracing options 2 (ftrace,
	lttng and perf)
Message-ID: <1290029498.4ce449ba1679d@www.imp.polymtl.ca>

Hi all,

This is a response to a benchmark, submitted a few weeks ago, comparing kernel
tracing options.
http://lkml.org/lkml/2010/10/28/422

We followed the methodology described in the link bellow,
but using the shellscripts posted there to reproduce autotest scripts.
http://lkml.org/lkml/2010/10/28/261

We disabled the extra syscall tracing on lttng, for a fair comparison.
http://lkml.org/lkml/2010/10/28/290

Average results with tracing "on":

lttng:  220 ns
ftrace: 260 ns
perf:   740 ns


E5405 system
kernel 2.6.36

-lttng 0.239 + 0.19.2modules + sys_getuid tracepoint + sys_getuid probe
 + remove syscall_trace

-ftrace and perf + sys_getuid tracepoint