From: "Mike Snitzer" Subject: help understanding the current (and future) state of NFSv4 locking? Date: Fri, 14 Nov 2008 15:34:56 -0500 Message-ID: <170fa0d20811141234m3faee54dh241b9a374b7201c@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Cc: linux-nfs@vger.kernel.org To: "J. Bruce Fields" Return-path: Received: from ik-out-1112.google.com ([66.249.90.179]:52777 "EHLO ik-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751129AbYKNUe7 (ORCPT ); Fri, 14 Nov 2008 15:34:59 -0500 Received: by ik-out-1112.google.com with SMTP id c29so1344554ika.5 for ; Fri, 14 Nov 2008 12:34:56 -0800 (PST) Sender: linux-nfs-owner@vger.kernel.org List-ID: Hello, I'd like to understand the state of Linux's NFSv4 server regarding the NFSv4 spec's _optional_ ordered blocking lock list implementation. Without something like the following patch isn't there still concern for NFSv4 clients being starved from ever getting a conflicting lock (local POSIX or lockd waiters would race to get it first)? "fair queuing" in Linux's fs/locks.c was developed but the patch was never merged upstream: http://www.citi.umich.edu/projects/nfsv4/linux/kernel-patches/2.6.13-1/linux-2.6.13-032-locks-posix-fair-queue.dif http://wiki.linux-nfs.org/wiki/index.php/Cluster_Coherent_NFS_and_Byte_Range_Locking http://www.eisler.com/2008-05-09/draft-ietf-nfsv4-minorversion1-23.html#blocking_locks I'd also like to understand: what Linux NFSv4.1 support is intended for the _optional_ CB_NOTIFY_LOCK?: 20.11. Operation 13: CB_NOTIFY_LOCK - Notify of possible lock availability: http://www.eisler.com/2008-05-09/draft-ietf-nfsv4-minorversion1-23.html#OP_CB_NOTIFY_LOCK Any insight would be appreciated. Thanks, Mike