Subject: Re: IFQ_MAXLEN: How large can it be?
To: Christoph Kaegi <kgc@zhwin.ch>
From: Thor Lancelot Simon <tls@rek.tjls.com>
List: tech-net
Date: 11/16/2006 10:15:56
On Thu, Nov 16, 2006 at 04:04:41PM +0100, Christoph Kaegi wrote:
> On 16.11-09:51, Thor Lancelot Simon wrote:
> > 
> > Of course.  You should also enable segmentation offload, if you haven't
> > already done so.
> 
> I'll do so tonight (as we have a maintenance window tonight)

It won't break anything; it is safe to turn on while your system is busy.

> > What value of HZ are you using?  Perhaps things are backing up because
> > the softnet processing is not happening often enough?
> 
> Never heard of this option before. options(4) doesn't go into 
> much details what this does. Could you explain its function
> to me?

It controls how often the system clock "ticks".  Much network processing
happens at the next clock tick after the network interrupt that
transfers the data from the network interface, not immediately upon
hardware interrupt, so it is possible that causing the clock to tick
more often may help with your problem.  Try a value of 1024.

Thor