[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: Slow ifconfig



Mirek Kwasniak wrote:
> On Tue, Oct 13, 1998 at 06:27:30PM +0000, Rene Hojbjerg Larsen wrote:
>> Somehow my ifconfig has become extremely slow.  I'm not sure exactly when
>> this happened, but it probably happened while upgrading to slink the other
>> day.
>> 
>> To give an example:
>> 
>> $ time /sbin/ifconfig >/dev/null
>> 
>> real    0m6.788s
>> user    0m4.450s
>> sys     0m1.590s
>> 
>> This used to take far less than a second...
>> 
[..]
>> 
>> Unless one of you has a solution, I will post a bug report.
> 
> I checked kerneld tries load modules or reread conf file many times
> executing modprobe and command from config like this:
> 
>   path[*]=/lib/modules/`uname -r`
>   path[*]=/lib/modules/`kernelversion`
> 
> On my station invocation of ifconfig execute about 160 processes:
> 
>>  22:06:59 3:2'kwasniak@mirek~$ ifconfig >/dev/null;ps tp3
>>    PID TTY STAT TIME COMMAND
>>  15329  p3 S    0:00 /bin/bash
>>  22506  p3 R    0:00 ps tp3
>>  22:09:58 3:2'kwasniak@mirek~$ ifconfig >/dev/null;ps tp3
>>    PID TTY STAT TIME COMMAND
>>  15329  p3 S    0:00 /bin/bash
>>  22672  p3 R    0:00 ps tp3
> 
> 22672-22506 = 166 !!!!!!!!
> 
> Bug should be posted against modutils:
> 
> $ time ifconfig
> real    0m4.923s  :(
> user    0m0.020s
> sys     0m0.000s
> $ killall kerneld  !!!!
> $ time ifconfig
> real    0m0.034s  :)
> user    0m0.010s
> sys     0m0.000s

You're absolutely right, the problem is with modutils.  My kmod executes,
among others, the following command while running ifconfig:

/sbin/modprobe -s -k net-pf-3

The execution of this command is very slow:

# time /sbin/modprobe -s -k net-pf-3

real    0m2.362s
user    0m1.520s
sys     0m0.620s

A full strace of this modprobe command (strace -f) comes in at about 13300
lines, so it is obviously doing a lot of (unnecessary) work.  I will try
to investigate further.
-- 
       /'"`\  zzzZ  | My PGP Public Key is available at:
      ( - - )       | <http://home1.inet.tele.dk/renehl/>
--oooO--(_)--Oooo------------------------------------------ 
 Don't ya just hate it when there's not enough room to fin 


Reply to: