Return-Path: Received: from acheron.ifi.lmu.de ([129.187.214.135]:47407 "EHLO acheron.ifi.lmu.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751211AbbGUGoq (ORCPT ); Tue, 21 Jul 2015 02:44:46 -0400 Message-ID: <55ADEA5C.8020607@bio.ifi.lmu.de> Date: Tue, 21 Jul 2015 08:44:44 +0200 From: Frank Steiner MIME-Version: 1.0 To: "J. Bruce Fields" CC: linux-nfs@vger.kernel.org Subject: Re: Parallel file locking quite slow with vers=4.0 compared to vers=3 References: <55ACFF59.7040707@bio.ifi.lmu.de> <20150720212305.GB11050@fieldses.org> In-Reply-To: <20150720212305.GB11050@fieldses.org> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-nfs-owner@vger.kernel.org List-ID: J. Bruce Fields wrote > One way to confirm that might be to run client kernels modified to make > the polling behavior (controlled by > fs/nfs/nfs4proc.c:nfs4_set_lock_task_retry()) more aggressive, and see > if that removes the delays in your case. > > If that works, then it might also be worth considering implementing > CB_NOTIFY_LOCK: > > https://tools.ietf.org/html/rfc5661#page-593 I wouldn't mind to test any kind of patch if someone would find the time to provide some. Writing them myself is beyond my skills I'm afraid :-) cu, Frank -- Dipl.-Inform. Frank Steiner Web: http://www.bio.ifi.lmu.de/~steiner/ Lehrstuhl f. Bioinformatik Mail: http://www.bio.ifi.lmu.de/~steiner/m/ LMU, Amalienstr. 17 Phone: +49 89 2180-4049 80333 Muenchen, Germany Fax: +49 89 2180-99-4049 * Rekursion kann man erst verstehen, wenn man Rekursion verstanden hat. *