From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: linux-nfs-owner@vger.kernel.org Received: from cantor2.suse.de ([195.135.220.15]:53714 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752204AbaGNCZk (ORCPT ); Sun, 13 Jul 2014 22:25:40 -0400 Date: Mon, 14 Jul 2014 12:25:31 +1000 From: NeilBrown To: Trond Myklebust Cc: Linux NFS Mailing List Subject: Re: [PATCH 0/7] Add RCU-walk support to NFS. Message-ID: <20140714122531.13a69cc8@notabene.brown> In-Reply-To: References: <20140714011630.12562.1940.stgit@notabene.brown> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/_jUkbxM5Gg5iqMb2SD.0Cm+"; protocol="application/pgp-signature" Sender: linux-nfs-owner@vger.kernel.org List-ID: --Sig_/_jUkbxM5Gg5iqMb2SD.0Cm+ Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Sun, 13 Jul 2014 22:00:12 -0400 Trond Myklebust wrote: > On Sun, Jul 13, 2014 at 9:28 PM, NeilBrown wrote: > > NFS current abort and attempt at filename lookup in RCU mode. > > This can have serious performance impact on a highly parallel load. > > > > The "Makefile" below generates just such a load. On a 40-core > > machine "make -j 40" is about 6 times as fast at "make -j 5" > > when a local filesystem is used (e.g. XFS), but as much as half > > as fast when NFS is used. > > With this patch set, "make -j 40" is about 3 times as fast as > > "make -j 5" on NFS, and "perf" data doesn't show spinlocks to be a big > > problem any more. > > > > This is a re-submission with a few small improvements of a patch set > > posted in March. Since then I have recieved confirmation that it > > definitely fixes the problem, when combined with a patch set which > > enhances autofs4 in a similar way. So it has had quite a bit of > > testing. >=20 > Hi Neil, >=20 > What kind of tests have you personally (or SuSE if relevant) performed? > Have you run this under NFSometer in order to check for regressions, > and if so on what workloads? >=20 > The above are not requirements in order to get the patches into > mainline, I'm just curious. I hadn't come across NFSometer before, looks useful! The only testing is that Makefile, and that was done mostly by the customer. Further, that testing was a version of the patchset for Linux 3.0. This particular patchset I've only tested lightly on my little 2-core test machine. I'm certainly happy to try beating on it a bit hard, and can see if I can g= et access to an 80-core machine that I had a brief play with a while back and = do some more testing there. NeilBrown --Sig_/_jUkbxM5Gg5iqMb2SD.0Cm+ Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIVAwUBU8M/mznsnt1WYoG5AQJEWg/8D48LdaezGaS7OMje/ZXIOwU4fpQeVkmE hJwW+EvZu+LkDgzOKkOGl4cmN8Do0oHrVchWdjYnwhcUtWp3vTPfq1aMbZwv/L47 TCnYQDA7KK1XzPxmVBmJxASLqEoJokp01bPXRbp5CJYBOmZWiYxRjF4ovuuLbFp3 q1CKArn4wUPhwbnw9xIHFnyvn7jToFLRWzPZDMueo09hUANNCvLyCvJsa9EXNx4S 9XbBVlfAY/ElH1x212C3qt1kZ7maOc5FWvLVOqX4ktqQHi3ME5qe0F4DCH5+DZnw jaRRFiVsn1cFDzKNc1H3S/4VmteairrwNJyS/pnBJGC2NHgbDWEplQ9yghaqzS6q yKQztTTC6rYN5/BcK5wHde/p0iD/YDZN5zTof61Ovi56dK4qoQ7kRsuQgRQtdfqm NpQ1E+z15eLa4q6qm60gn9nQSYdioROJPxRH85mwp/QizP2DU7Pwjyuh5HIqvWyg vXIlvHewVyGnBRNaEZ9TIRhs/B5AW5zt8LqmVCbE2LpdoriAKtsltcI1wFG7N+zT 9Cl47Lz2zs0patbvsz3bww9i0it406fDsfwlhJRepySl/CCS5SkpHX1w3Hz/7kQm 98KM/CSlbqJc8+x0gtxb/1GFwm6dNTOFh3Wfnn0tsbXNRuqUKcfwZ7XFv528DBgb pJQoVLp9X60= =wyPT -----END PGP SIGNATURE----- --Sig_/_jUkbxM5Gg5iqMb2SD.0Cm+--