Return-Path: Received: from mail-vn0-f46.google.com ([209.85.216.46]:44356 "EHLO mail-vn0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753756AbbGBXX2 (ORCPT ); Thu, 2 Jul 2015 19:23:28 -0400 Received: by vnbg129 with SMTP id g129so7172592vnb.11 for ; Thu, 02 Jul 2015 16:23:27 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <1435877253-1497-1-git-send-email-mchen@cs.stonybrook.edu> References: <1435877253-1497-1-git-send-email-mchen@cs.stonybrook.edu> Date: Thu, 2 Jul 2015 19:23:27 -0400 Message-ID: Subject: Re: [PATCH] nfs: avoid nfs_wait_on_seqid() for NFSv4.1 From: Trond Myklebust To: Ming Chen Cc: Linux NFS Mailing List , Linux FS-devel Mailing List , ezk@fsl.cs.stonybrook.edu Content-Type: text/plain; charset=UTF-8 Sender: linux-nfs-owner@vger.kernel.org List-ID: On Thu, Jul 2, 2015 at 6:47 PM, Ming Chen wrote: > > seqid, introduced in NFSv4.0, requires state-changing operations be performed > synchronously, and thus limits parallelism. NFSv4.1 supports "unlimited > parallelism" by using sessions and slots; seqid is no longer used and must be > ignored by NFSv4.1 server. However, the current nfs client always call > nfs_wait_on_seqid() no matter the version is 4.0 or 4.1. Please see commit 63f5f796af613 ("NFSv4.1: Allow parallel OPEN/OPEN_DOWNGRADE/CLOSE") which first appeared in Linux-4.0. Cheers Trond