Re: Timing comparisons for multi-kprobe feature

[Hien Nguyen <hien at us dot ibm dot com>]

Hi Ananth, Will,

I can't explain this but this the output for my timing_kprobe, which my 
calculation yeilds 1 for both kprobe and jprobe

Apr 18 15:58:02 elm3b99 kernel: kprobe registered
Apr 18 15:58:02 elm3b99 kernel: plant jprobe at f8a002b0, handler addr 
f8a00030
Apr 18 15:58:12 elm3b99 kernel: kprobe start 5169729839300, stop 
5170565252311
Apr 18 15:58:12 elm3b99 kernel: kprobe overhead count 1000000, number of 
cycles 835413011
Apr 18 15:58:14 elm3b99 kernel: jprobe start 5170565271260, stop 
5171945384508
Apr 18 15:58:14 elm3b99 kernel: jprobe overhead count 1000000, number of 
cycles 1380113248
Apr 18 15:58:15 elm3b99 kernel: kprobe start 5171945399260, stop 
5172780564338
Apr 18 15:58:15 elm3b99 kernel: kprobe overhead count 1000000, number of 
cycles 835165078
Apr 18 15:58:17 elm3b99 kernel: jprobe start 5172780578137, stop 
5174156636912
Apr 18 15:58:17 elm3b99 kernel: jprobe overhead count 1000000, number of 
cycles 1376058775
Apr 18 15:58:17 elm3b99 kernel: kprobe unregistered
Apr 18 15:58:17 elm3b99 kernel: jprobe unregistered


Ananth N Mavinakayanahalli wrote:

> Hi,
>
> Here is the result of the tests I carried out to determine the cost
> of the multiple-kprobes feature. All tests were carried out on a
> uni PIII running at 732MHz.
>
> I used Will's timing_kprobe and kprobe_multi modules on linux-2.6.12-rc2
> for the tests.
>
> (All values in microseconds)
>
>         Vanilla        Single        Multiple
>         (2.6.12-rc2)    Interface    Interfaces
> ------------------------------------------------------------
> kprobe        1.124        1.149        1.149
> jprobe        1.891        1.885        1.885
> kprobe_multi    NA        1.306        1.387
>
> Note:
> - Single Interface => linux-2.6.12-rc2 + take3 patch
> - Multiple Interfaces => linux-2.6.12-rc2 + take4 patch
> - kprobe_multi => averaged values with Will's kprobe_multi testcase
>
> Thanks,
> Ananth