From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: Re: [PATCH 00/20] Support follow_link in RCU-walk - V3 Date: Thu, 26 Mar 2015 10:23:52 +1100 Message-ID: <20150326102352.0250cfd2@notabene.brown> References: <20150323023258.8161.32467.stgit@notabene.brown> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; boundary="Sig_/Ru2PF=Ib3zpNhJ9j2OnXB5a"; protocol="application/pgp-signature" Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: Al Viro Return-path: Received: from cantor2.suse.de ([195.135.220.15]:38227 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750821AbbCYXYA (ORCPT ); Wed, 25 Mar 2015 19:24:00 -0400 In-Reply-To: <20150323023258.8161.32467.stgit@notabene.brown> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: --Sig_/Ru2PF=Ib3zpNhJ9j2OnXB5a Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Mon, 23 Mar 2015 13:37:38 +1100 NeilBrown wrote: > Hi Al, > thanks for all your review help - particularly the fact that > dentry->d_inode is not stable in RCU-walk. That has lead to > a number of changes. >=20 > I think this set addresses all of your review comments, improves > some documentation, and has a go at providing a solution for lustre. >=20 > I hope to organize some proper testing soon, so I can confirm that it > makes certain loads a lot faster. Just FYI - I've now tested this series on a 64-CPU machine running load that has lots of threads doing lots of stats on lots of non-existent files. Without the patches, the test takes twice as long if there is a symlink ear= ly in the path for the stats, than if there is not. With the patches, there is no significant difference in the time the test takes between the symlink and no-symlink cases. So it appears to be achieving the goal. Thanks, NeilBrown --Sig_/Ru2PF=Ib3zpNhJ9j2OnXB5a Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIVAwUBVRNDiDnsnt1WYoG5AQKPPA/9E1QGaxu/GRFc7zxKxPawrhkjHuGjfw6t 2TDPMp92EPAp9rYk3Z6jObVrNTcgtnVN3nSZrJBRN3AIaTSmdMF8CZmgECTyP4al 2FXrYxsvmGiFpm52bS4Oe42dvt3AoC9eUcazFRVfpCZUy8ruLFUJAl1Hy4KCVbQF IlaedFK0U+t8RrCPCGS5sXM7nKa0Xe5+UWOGEx9q1SK4+6XejAEInihodyR7vB1M ZTIfbBdaUBc//DsF+NoO6FVxzOXOB3wbGv8LTVltTZ2lPLP5gm2Kq9L5/HQ9RD1E vTCRRnRtBg7ZhJjKEdBeTDkOFg7kGqeZzo2wQe9I2PKm44TojXXDFFZxLe8Yx0Dr Z6+5NN+d+TpuGb8rYrWaFJ9zdclxA+Acb8zMQaYFSidSzj80daPxRCkODg/2uhP1 Z56OcpkNbh5fKK7iT4H6X4NnSyUM+uaxim/tqT6OIo++BFCV0zNl+n5f8DNS7ti4 IFQG6Eb/Z5WRGOXWwUonQjj/jwyFald+4tGtKO5qzMom+EAlHF0odiqThPei+AGZ 4BuXwGeTSJL+IlRJnyfXMalWm4SjAvug+9AMuuHjj9yDc6XYtYGx3Ipls9qv1SQd +tWzLt7DmrQEhdLNeENpNxwa2Oq5Q22BgjOOxsCPCKTOQbZZRpEtW7e9p30gai52 c3VGVkAQWHo= =cFn0 -----END PGP SIGNATURE----- --Sig_/Ru2PF=Ib3zpNhJ9j2OnXB5a--