[ltt-dev] Benchmarks of kernel tracing options 2 (ftrace, lttng and perf)

[rostedt@goodmis.org (Steven Rostedt)]

On Wed, 2010-11-17 at 16:31 -0500, Douglas Santos wrote:
> 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

Heh, so ftrace got worse with the new kernel?

-- Steve

> 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