From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: RE: [E1000-devel] [e100] Page allocation failure warning(?) in 2.6.36.3 Date: Thu, 13 Jan 2011 10:05:56 +0100 Message-ID: <1294909556.3570.25.camel@edumazet-laptop> References: <895344.13845.qm@web121707.mail.ne1.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: JesseBrandeburg , David Miller , "e1000-devel@lists.sourceforge.net" , Tushar NDave , "netdev@vger.kernel.org" , Jeffrey TKirsher To: Chris Rankin Return-path: Received: from mail-ww0-f42.google.com ([74.125.82.42]:49091 "EHLO mail-ww0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932429Ab1AMJGC (ORCPT ); Thu, 13 Jan 2011 04:06:02 -0500 Received: by wwi17 with SMTP id 17so4841566wwi.1 for ; Thu, 13 Jan 2011 01:06:00 -0800 (PST) In-Reply-To: <895344.13845.qm@web121707.mail.ne1.yahoo.com> Sender: netdev-owner@vger.kernel.org List-ID: Le jeudi 13 janvier 2011 =C3=A0 01:00 -0800, Chris Rankin a =C3=A9crit = : > --- On Thu, 13/1/11, Eric Dumazet wrote: > > Problem is e100 allocates an order-6 page in DMA zone > > (a 256 KB contigous area of ram) > >=20 > > This contigous area of ram is not available but just after > > booting... >=20 > I suspected as much. Fortunately, this machine has no function apart = from routing and can happily left untouched for extended periods of tim= e. >=20 > > On such small router, I doubt you need more than 64 slots > > in TX ring buffer. >=20 > But what would the effect of that change be to the interfaces' perfor= mance, please? If you care of performance, dont unload/reload your driver all the time= , and dont use modules (this matter on old hardware because of TLB misses= ) Anyway, the change ( 128 -> 64 ) is not needed, since the kernel messag= e is a warning only. The allocation is retried and apparently succeeds. The __GFP_NOWARN should make the failed allocation not noticed at all.