Subject: Re: regression: unregister_netdev() unusably slow

From: Eric Dumazet <[email-masked]>
Date: Mon, 25 May 2009 00:07:07 +0200

Benjamin LaHaise a écrit :
> On Sun, May 24, 2009 at 11:42:17PM +0200, Eric Dumazet wrote:
>> (But vlan case might be litle bit more expensive than your case, since we call
>> synchronize_net() three times (once in unregister_vlan_dev(), and twice in rollback_registered()
> 
> I did try commenting out the synchronize_net() calls in rollback_registered(), 
> but that had almost no effect on the rate of interface deletion.  50ms is 
> still way too expensive.
> 
> 		-ben

Maybe your HZ is too low ? Changing to 1000 HZ helps a lot

Also your hotplug config might do strange things at device removal ?

What distro do you use ?