Re: [Help-gnunet] OK to use a FQDN for 'IP' in gnunet.conf?

[Ludovic Courtès]

Hi,

One day, 22 hours, 51 minutes, 26 seconds ago, 
Milan wrote:
> in the list, top shows that the first procees to use CPU is XFree with
> only 11%. gnunetd doesn't appear.

This may be due to top's failure of accounting for the CPU time of
gnunetd's threads (if you're running a 2.6 kernel).  I observe the same
thing and this seems to be a know problem [1].

However, here are further evidences.  :-)

I ran gnunetd for approximately half an hour and used `ps' to get more
accurate information on what's going on.  It was connected to 17 nodes
at the end.  While my `MAXCPULOAD' was set to 20, gnunetd was clearly
eating 100% of the CPU time:

  [ludo ~]$ ps -m --cumulative --format "pid command %cpu time wchan" 958
    PID COMMAND          %CPU     TIME WCHAN
    958 /usr/bin/gnunetd  0.0 00:00:01 -
      - -                 0.0 00:00:01 schedule_timeout
      - -                 0.0 00:00:00 schedule_timeout
      - -                34.0 00:22:28 schedule_timeout
      - -                33.1 00:21:52 -
      - -                 0.2 00:00:10 schedule_timeout
      - -                 0.0 00:00:01 schedule_timeout
      - -                13.7 00:09:04 schedule_timeout
      - -                 2.7 00:01:48 schedule_timeout

This shows that 8 threads (not 9) have been running.  Three of those
threads have been sharing the whole CPU time while the others have been
mostly sleeping.  The `WCHAN' field shows "the name or the address of
the kernel function in which the task is currently sleeping", or a dash
for running threads (quoting the `top' manual page).  So the idle
threads are effectively waiting for I/O or for a sleep(3) timeout (see,
e.g., `io_schedule_timeout' in Linux' `kern/sched.c').

Now, we need to identify the working threads and see why they are
working so much.  ;-)  Christian, if you know the order in which threads
are spawned, assuming the first thread shown by `ps' is the main thread,
you might be able to tell us more about it?

Thanks,
Ludovic.

PS: Should we rather use `gnunet-developers' for this sort of
    discussion?

[1] See, e.g., http://support.novell.com/products/tips/10007.html
    http://www.ussg.iu.edu/hypermail/linux/kernel/0410.0/1244.html .