From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?B?TmVib2rFoWEgxIZvc2nEhw==?= Subject: Re: e1000e 82574L transmit latency? Date: Tue, 28 May 2013 16:09:07 +0200 Message-ID: <20130528160907.2d98fc65@sth491dt.servo.net> References: <51A4A6F7.5090909@meduna.org> <20130528150135.41a6d6fb@sth491dt.servo.net> <51A4B5F9.6010206@meduna.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: "linux-rt-users@vger.kernel.org" To: Stanislav Meduna Return-path: Received: from smtprelay-h22.telenor.se ([195.54.99.197]:33686 "EHLO smtprelay-h22.telenor.se" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933933Ab3E1OJM convert rfc822-to-8bit (ORCPT ); Tue, 28 May 2013 10:09:12 -0400 Received: from ipb5.telenor.se (ipb5.telenor.se [195.54.127.168]) by smtprelay-h22.telenor.se (Postfix) with ESMTP id 9D4F7C07B for ; Tue, 28 May 2013 16:09:10 +0200 (CEST) In-Reply-To: <51A4B5F9.6010206@meduna.org> Sender: linux-rt-users-owner@vger.kernel.org List-ID: =D0=94=D0=B0=D0=BD=D0=B0 Tue, 28 May 2013 15:49:45 +0200 Stanislav Meduna =D0=BD=D0=B0=D0=BF=D0=B8=D1=81=D0=B0= : > On 28.05.2013 15:01, Neboj=C5=A1a =C4=86osi=C4=87 wrote: >=20 > > If you are having several processes/threads with different prioriti= es > > sending on same eth, combined with high cpu load on RT processes, t= han > > it sounds a lot like a problem I had: Check > > http://article.gmane.org/gmane.linux.rt.user/10163 for details >=20 > Hm, interesting. However, there is just one thread sending on the > interface and all threads with higher priority generally only run for > brief intervals and do not do anything with ethernet. There are > lower-prio threads doing full TCP/IP but they communivate on another > interface (also a e100e one). >=20 > Thanks Well, I think it still applies. Lock which is responsible for this problem is driver wise... Lower prio thread can take driver lock, and thus delay higher thread from accessing driver. It is enough that there are jobs with higher prio than lowest prio tcp/ip sending thread, even if they have nothing to do with network. --=20 Neboj=C5=A1a -- To unsubscribe from this list: send the line "unsubscribe linux-rt-user= s" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html