Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752095AbYAOPXz (ORCPT ); Tue, 15 Jan 2008 10:23:55 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751105AbYAOPXp (ORCPT ); Tue, 15 Jan 2008 10:23:45 -0500 Received: from chello089077127128.chello.pl ([89.77.127.128]:45659 "EHLO astralstorm.puszkin.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751001AbYAOPXo (ORCPT ); Tue, 15 Jan 2008 10:23:44 -0500 X-Greylist: delayed 384 seconds by postgrey-1.27 at vger.kernel.org; Tue, 15 Jan 2008 10:23:43 EST Date: Tue, 15 Jan 2008 16:17:05 +0100 From: Radoslaw Szkodzinski (AstralStorm) To: "Chris Friesen" Cc: Jarek Poplawski , David Miller , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: questions on NAPI processing latency and dropped network packets Message-ID: <20080115161705.0724250d@astralstorm.puszkin.org> In-Reply-To: <478CC76B.1020804@nortel.com> References: <20080115071950.GA1696@ff.dom.local> <478CC76B.1020804@nortel.com> X-Mailer: Claws Mail 3.2.0 (GTK+ 2.12.5; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: multipart/signed; boundary="Sig_/8tJObg510IBp.7DfwEaB7GX"; protocol="application/pgp-signature"; micalg=PGP-SHA1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2394 Lines: 66 --Sig_/8tJObg510IBp.7DfwEaB7GX Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Tue, 15 Jan 2008 08:47:07 -0600 "Chris Friesen" wrote: > Jarek Poplawski wrote: >=20 > > IMHO, checking this with a current stable, which probably you are going > > to do some day, anyway, should be 100% acceptable: giving some input to > > netdev, while still working for yourself. >=20 > While I would love to do this, it's not that simple. >=20 > Some of our hardware is not supported on mainline, so we need per-kernel= =20 > version patches to even bring up the blade. The blades netboot via a=20 > jumbo-frame network, so kernel extensions are needed to handle setting=20 > the MTU before mounting the rootfs. Why? Can't you use a small initramfs to set it up? > The blade in question uses CKRM=20 > which doesn't exist for newer kernels so the problem may simply be=20 > hidden by scheduling differences. Current spiritual successor is Ingo's realtime patchset I guess. > The userspace application uses other=20 > kernel features that are not in mainline (and likely some of them won't=20 > ever be in mainline--I know because I've tried). What would these be? Some proc or sysfs files that were removed or renamed? Maybe they can be worked around w/o changing the application at all, or very minor changes. Also, be sure to check if there are pauses with other CPU hogs. > Basically, the number of changes required for our environment makes it=20 > difficult to just boot up the latest kernel. Yes, adding an initramfs is non-trivial (some busybox + shell scripting), but not all that hard either. And maintaining one is easier than patching the kernel. (usually 0 maintenance, maybe minor fixes sometimes) --Sig_/8tJObg510IBp.7DfwEaB7GX Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.8 (GNU/Linux) iEYEARECAAYFAkeMznoACgkQBlhXA0ALOYMwvACgkLIEPeMlYnCDE/ylqXZl+OU2 TkgAnR1FlNKBsGNvJhPY+hbbawXi5dEh =T8Zj -----END PGP SIGNATURE----- --Sig_/8tJObg510IBp.7DfwEaB7GX-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/