[Click] insmod: error inserting '/usr/local/lib/click.ko': -1 Cannot allocate memory

[Daniel Borkmann]

Hi Cliff,

On Wed, Oct 5, 2011 at 7:15 PM, Cliff Frey <cliff at meraki.com> wrote:
> You could try adding BURST 10 or something to your FromDevice configuration
> and see if that makes a difference.
> You could also try changing tasks_per_iter (there is a top level handler, so
> you could add "Script(write tasks_per_iter 300)" to your config).
> I don't actually think that either of the above will make much difference...
> as I believe that the click task should currently try and send 128 packets
> each time it is scheduled (tasks_per_iter * BURST == 128 * 1 == 128).
>  However, the BURST one is definitely worth trying.
> You could also try changing the "weight" on your ethernet driver, but that
> also should default to 64 or higher, so I don't understand how/why so few
> packets would be processed each time.
> If you run ifconfig after the test, are there any error counters that are
> very high?

Thanks for the hints.

No, there aren't any error values on the NIC driver. If I turn off
click (click-uninstall), then the packet rate rises up to approx 1,38
Mio pps (receive and drop by the kernel) and the context switch rate
decreases to less than 1000 per sec. I tried the whole experiment
multiple times - each time the same as described. Is the click kernel
thread running in high-priority or RT mode? This could maybe explain
the starvation of the ksoftirqd.

Thanks,
Daniel

> Cliff
> On Wed, Oct 5, 2011 at 8:58 AM, Daniel Borkmann <borkmann at iogearbox.net>
> wrote:
>>
>> On Wed, Oct 5, 2011 at 4:06 PM, Eddie Kohler <kohler at cs.ucla.edu> wrote:
>> > I'm thinking probably we should do that automatically.
>>
>> Hmm, if someone wants to do debugging, then it might not work (since
>> the syms are stripped), except you have a special target for debug,
>> for instance.
>>
>> What I recently noticed running Click in kernelspace: the number of
>> context switches per second is very high (... too high) on a high
>> packet rate. More details:
>>
>> I have two machines Intel Core 2 Quad Q6600 CPU, 4 GB RAM, Intel
>> 82566DC Ethernet Controller (e1000e driver). Both have Debian 6.0. One
>> machine has a vanilla Linux 3.0 running pktgen with 64 Byte packets
>> (max. load), the other one is running Linux 2.6.38 with click in
>> kernelspace. Both are directly connected. The config is:
>> source::FromDevice(eth0); drop::SimpleIdle; source->drop. I was
>> measuring packets per second and the system's context switches per
>> second, both gathered from procfs. The result was that I reached about
>> 460k pps while having a context switch rate of about 200k cs/sec (!).
>> (The high rate explains the rather low pps rate.) Running
>> (multithreaded) click in userspace on top of Linux 3.0, I got about
>> 545k pps and less than 1000 cs/sec.
>>
>> Has anyone measured similar values? Could it be, that the click kernel
>> thread is pushing away CPU time for the ksoftirqd doing NAPI (sofirqs
>> for RX) on the e1000e?
>>
>> Thanks,
>> Daniel
>>
>> >
>> > Eddie
>> >
>> > On 10/5/11 9:32 AM, Daniel Borkmann wrote:
>> >>
>> >> Hi Sandeep,
>> >>
>> >> thanks for your reply! :-)
>> >>
>> >> Stripping the debug symbols out of the module like ...
>> >>
>> >> root at xyz:~# strip -g /usr/local/lib/click.ko
>> >>
>> >> ... worked for me; I already was on the latest Git repository.
>> >>
>> >> Thanks,
>> >> Daniel
>> >>
>> >> On Wed, Oct 5, 2011 at 3:14 PM, sandeep<sandeep048 at gmail.com>  wrote:
>> >>>
>> >>> I also had the same problem but it disappeared after I updated to the
>> >>> latest
>> >>> git repository. https://github.com/kohler/click/tarball/master
>> >>>
>> >>> Kind Regards,
>> >>> Sandeep,
>> >>> PhD Student,
>> >>> CTVR - Trinity College Dublin
>> >>> On Wed, Oct 5, 2011 at 1:36 PM, Daniel
>> >>> Borkmann<borkmann at iogearbox.net>
>> >>> wrote:
>> >>>>
>> >>>> Hi list,
>> >>>> I managed to build the patchless Click kernel version under 2.6.38,
>> >>>> but insmod fails with the following:
>> >>>>
>> >>>> root at pc-10089:~# click-install forw.click
>> >>>> insmod: error inserting '/usr/local/lib/click.ko': -1 Cannot allocate
>> >>>> memory
>> >>>> click-install: '/sbin/insmod /usr/local/lib/click.ko' failed
>> >>>>
>> >>>> Any ideas? Did anyone have same issues?
>> >>>>
>> >>>> Thanks,
>> >>>> Daniel
>> >>>> _______________________________________________
>> >>>> click mailing list
>> >>>> click at amsterdam.lcs.mit.edu
>> >>>> https://amsterdam.lcs.mit.edu/mailman/listinfo/click
>> >>>
>> >>>
>> >>
>> >>
>> >>
>> >
>>
>>
>>
>> --
>> Web: http://gnumaniacs.org
>>
>> _______________________________________________
>> click mailing list
>> click at amsterdam.lcs.mit.edu
>> https://amsterdam.lcs.mit.edu/mailman/listinfo/click
>
>



-- 
Web: http://gnumaniacs.org