Re: dhclient taking all cpu

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.
> 

-- 
Wilko Bulte				wilko_at_FreeBSD.org