dummynet dropping too many packets

rihad rihad at mail.ru
Wed Oct 7 14:43:59 UTC 2009


Robert Watson wrote:

> I would suggest making just the HZ -> 4000 change for now and see how it 
> goes.
> 
OK, I will try testing HZ=4000 tomorrow morning, although I'm pretty 
sure there still will be some drops.

>> Can someone please say how to increase the "ifnet transmit queue sizes"?
> 
> Unfortunately, I fear that this is driver-specific, and in the case of 
> bce requires a recompile.  In the driver init code in if_bce, the 
> following code appears:
> 
>         ifp->if_snd.ifq_drv_maxlen = USABLE_TX_BD;
>         IFQ_SET_MAXLEN(&ifp->if_snd, ifp->if_snd.ifq_drv_maxlen);
>         IFQ_SET_READY(&ifp->if_snd);
> 
> Which evaluates to a architecture-specific value due to varying 
> pagesize.  You might just try forcing it to 1024.
> 
I think I'll try this too, if HZ=4000 doesn't help, thanks a lot.
In the long run we'll switch to some high-quality 10 GiGE cards.


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