Return-Path: Received: from bombadil.infradead.org ([198.137.202.9]:54117 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752383AbbCYIzw (ORCPT ); Wed, 25 Mar 2015 04:55:52 -0400 Date: Wed, 25 Mar 2015 01:55:50 -0700 From: Christoph Hellwig To: Trond Myklebust Cc: Tigran Mkrtchyan , Linux NFS Mailing List Subject: Re: [PATCH 4/4] NFSv4.1: Don't cache deviceids that have no notifications Message-ID: <20150325085550.GA23258@infradead.org> References: <1425931503-37261-1-git-send-email-trond.myklebust@primarydata.com> <1425931503-37261-2-git-send-email-trond.myklebust@primarydata.com> <1425931503-37261-3-git-send-email-trond.myklebust@primarydata.com> <1425931503-37261-4-git-send-email-trond.myklebust@primarydata.com> <1425931503-37261-5-git-send-email-trond.myklebust@primarydata.com> <20150317103736.GA31940@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-nfs-owner@vger.kernel.org List-ID: On Sun, Mar 22, 2015 at 03:27:32PM -0400, Trond Myklebust wrote: > No. The right fix is to make the server support device notifications. And you instantly thrash performane on any server that doesn't, which is why I sent out the errata that no one objected out. I'm happy to open this again on the WG list, but the notification scheme is such a big hammer that it absolutely isn't worth implementing. Given how GETDEVICELIST is specified in 4.1 the original RFC language also is inconsistent with itself, so that's not an argument for the old behavior.