Re: [E1000-devel] e1000 1sec latency problem

From: Kok, Auke
Date: Thu Feb 07 2008 - 13:14:25 EST


Max Krasnyansky wrote:
> Kok, Auke wrote:
>> Max Krasnyansky wrote:
>>> So you don't think it's related to the interrupt coalescing by any chance ?
>>> I'd suggest to try and disable the coalescing and see if it makes any difference.
>>> We've had lots of issues with coalescing misbehavior. Not this bad (ie 1 second) though.
>>>
>>> Add this to modprobe.conf and reload e1000 module
>>>
>>> options e1000 RxIntDelay=0,0 RxAbsIntDelay=0,0 InterruptThrottleRate=0,0 TxIntDelay=0,0 TxAbsIntDelay=0,0
>> that can't be the problem. irq moderation would only account for 2-3ms variance
>> maximum.
> Oh, I've definitely seen worse than that. Not as bad as a 1second though. Plus you're talking
> about the case when coalescing logic is working as designed ;-). What if there is some kind of
> bug where timer did not expire or something.

we don't use a software timer in e1000 irq coalescing/moderation, it's all in
hardware, so we don't have that problem at all. And I certainly have never seen
anything you are referring to with e1000 hardware, and I do not know of any bug
related to this.

are you maybe confused with other hardware?

feel free to demonstrate an example...

Cheers,

Auke
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/