dhclient taking all cpu

[Eric Anderson]

Eric Anderson wrote:
> Wilko Bulte wrote:
> 
>> On Tue, Jul 26, 2005 at 02:56:36PM -0500, Eric Anderson wrote..
>>
>>> Brooks Davis wrote:
>>>
>>>> On Mon, Jul 25, 2005 at 10:39:09PM -0400, Mike Jakubik wrote:
>>>>
>>>>
>>>>> On Mon, July 25, 2005 9:54 pm, Brooks Davis said:
>>>>>
>>>>>
>>>>>
>>>>>>>> Probably something wrong with your interface, but you havent't
>>>>>>>> provided any useful information so who knows.  At the very least, I
>>>>>>>> need to know what interface you are running on, something about 
>>>>>>>> it's
>>>>>>>> status, and if both dhclient processes are running.
>>>>>>>>
>>>>>>>
>>>>>>> The interface is xl0 (3Com 3c905C-TX Fast Etherlink XL), and it 
>>>>>>> worked
>>>>>>> in this machine fine for as long as i remember. This seems to have
>>>>>>> happened since a recent cvsup and buildworld from ~6-BETA to 
>>>>>>> 7-CURRENT.
>>>>>>> I rebooted three times, and the problem occured rougly a minute 
>>>>>>> after
>>>>>>> bootup. On the fourth time however, it seems to be ok so far.
>>>>>>
>>>>>>
>>>>>> That sounds like a problem with the code that handles the link state
>>>>>> notifications in the interface driver.  The notifications are a 
>>>>>> reletivly
>>>>>> new feature that we're only now starting to use heavily so there 
>>>>>> are going
>>>>>> to be bumps in the road.  It would be intresting to know if you 
>>>>>> see link
>>>>>> state messages promptly if you plug and unplug the network cable.
>>>>>
>>>>>
>>>>> It seems to be back at it again, this time it took longer to kick 
>>>>> in. Here
>>>>> is a "ps auxw|grep dhclient" :
>>>>>
>>>>> _dhcp      219 93.5  0.2  1484  1136  ??  Rs    8:49PM   5:06.00 
>>>>> dhclient:
>>>>> xl0 (dhclient)
>>>>> root       193  0.0  0.2  1484  1088  d0- S     8:49PM   0:00.02 
>>>>> dhclient:
>>>>> xl0 [priv] (dhclient)
>>>>>
>>>>> top:
>>>>>
>>>>> PID USERNAME      THR PRI NICE   SIZE    RES STATE    TIME   WCPU 
>>>>> COMMAND
>>>>> 219 _dhcp           1 129    0  1484K  1136K RUN      9:33 94.24% 
>>>>> dhclient
>>>>>
>>>>> Nothing in dmesg about link state changes on xl0. Unplugging and
>>>>> replugging the network cable results in link state notification 
>>>>> within a
>>>>> couple seconds.
>>>>
>>>>
>>>>
>>>> Could you see what happens if you run dhclient in the foreground?  Just
>>>> running "dhclient -d xl0" should do it.  I'd like to know what sort of
>>>> output it's generating.
>>>
>>>
>>> I have the same issue (with ath0).  However, running it in the 
>>> foreground doesn't show the problem.  It seems to only break on bootup 
>>
>>
>>
>> In my case it does happend with dhclient in the foreground, and on ath(4)
>>
>>
>>> for me.  Even running netif stop/start seems ok after I've killed it 
>>> initially.  It seems to be bringing ath0 up/down/up/down/etc when 
>>> it's hogging CPU.
> 
> 
> You know, the second I sent that email, it went crazy.  Looks like it 
> was 5 minutes.  But if I kill it, and run with -d, I don't see any extra 
> output.

Actually, make that 4 minutes.  Need a core file?


Eric



-- 
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Eric Anderson        Sr. Systems Administrator        Centaur Technology
Anything that works is better than anything that doesn't.
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