(2013/12/20 5:46), Frank Ch. Eigler wrote:
>
> Hi, Masami -
>
>
> masami.hiramatsu.pt wrote:
>
>> Here is the version 6 of NOKPROBE_SYMBOL series. :)
>> [...]
>
> Some preliminary results from building these on top of tip/master on
> x86-64.
>
> # stap -te "probe kprobe.function("*") {}"
>
> starts up OK, without crashes, which looks like great progress.
That's a good news :)
> But a
> closer look indicates that the insertion of kprobes is taking about
> three (!!) orders of magnitude longer than before, as judged by the
> rate of increase of 'wc -l /sys/kernel/debug/kprobes/list'.
Right, because kprobes are not designed for thousands of probes.
> So, one
> has to let the thing run for several hours just to get all the kprobes
> inserted, never mind letting stress-testing begin.
>
> For reference, here's the steady-state "perf top" output during all this
> insertion work:
>
> 54.81% [kernel] [k] _raw_spin_unlock_irqrestore
> 38.13% [kernel] [k] __slab_alloc
> 1.11% [kernel] [k] kprobe_ftrace_handler
> 0.88% [kernel] [k] _raw_spin_unlock_irq
Hmm, interesting. Those probes are registered as disabled?
Thank you,
--
Masami HIRAMATSU
IT Management Research Dept. Linux Technology Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: masami.hiramatsu.pt@xxxxxxxxxxx
--
To unsubscribe from this list: send the line "unsubscribe linux-arch" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
