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]:45112 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752883AbaGHG5e (ORCPT ); Tue, 8 Jul 2014 02:57:34 -0400 Date: Tue, 8 Jul 2014 16:57:27 +1000 From: NeilBrown To: Christoph Hellwig Cc: Trond Myklebust , Chuck Lever , NFS Subject: Re: Is there a good reason that nfs4_state_manager should use a work_queue? Message-ID: <20140708165727.7095e209@notabene.brown> In-Reply-To: <20140708064641.GA16497@infradead.org> References: <20140708152100.67cd93c7@notabene.brown> <20140708064641.GA16497@infradead.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/aYJOvA2Xu8J+uUEtyJ.DL+W"; protocol="application/pgp-signature" Sender: linux-nfs-owner@vger.kernel.org List-ID: --Sig_/aYJOvA2Xu8J+uUEtyJ.DL+W Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Mon, 7 Jul 2014 23:46:41 -0700 Christoph Hellwig wro= te: > On Tue, Jul 08, 2014 at 03:21:00PM +1000, NeilBrown wrote: > > 2/ would it be reasonable to have a single work queue for all nfs clie= nts? > > In the worst case this could serialise reclaim across all clients s= o we > > wouldn't want any reclaim attempt to block indefinitely. Is that l= ikely > > to be a big problem do you think? >=20 > A workqueue isn't serialized, it has a max_active paramater to control > the concurrency of execution. True, but if memory is tight it may not be able to create new threads. WQ_MEM_RECLAIM guarantees there will be at least one, but worst-case that might be all that we have. Thanks, NeilBrown --Sig_/aYJOvA2Xu8J+uUEtyJ.DL+W Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIVAwUBU7uWWDnsnt1WYoG5AQI20hAAsxauQZjITeHvaFLfnB2OYisQOHIZhcjv KBi+g0YQetNX6r3QFZrOiBOrmDge6hE8IpMY5Tt7nzNm50esChhoY8/DiuxjSm2o cpYQjJMEpvw9JUAlfHGSQs+BaYOPaDvEoMRlTObPFCQbFkqLGmyvHA5l143fIMS4 lNR3+dToKrdhXL5BuE9DSMUyKRl0CwFKTg7dvxpgvQ9N4nzmvsRoSH9+lrJ17djI g4nZZ8BcDznvyicxiMfb1vzJ5I2E5ppHKk6dW3RZ5KZrZVhdiG7ounUgHXvXS61B T0JkS5YQylGpuBreHqCFYvp21UcjNhWQioqxnMrXppXiVf4SGQya1OS1e81rSONU xClufjwfw5qkWFETC1BWLXlCNLQVorjIuBrpH6ToFdpBU36RIdB2YomI/gaFFkK0 YWveqeFkhKJoiRsmuq0a5DpZ7SvSOfn4gW5o0J6Uc/vin7nwW+9Kmq4+pXEaN/oX y9P1oNNoA0V96ZwuDnm8wsE+TFs2g3Xz3thlyyViXukbn0ukkS3YM5BOypQ0iefF qrtZvaZelm4/iwPGoCuJ7oNdKcwXhuOprVwBkURoAd9nEaaIyvrZdl4KzOimg7Qu 0nxqHVvaRpSty+9PI7RVeNu2d+dIYTK3saCZ3bTmRLv4Iq6kmZFbLSUtPKBn40Ht Qow9xa7F9bA= =1x1a -----END PGP SIGNATURE----- --Sig_/aYJOvA2Xu8J+uUEtyJ.DL+W--