Return-Path: linux-nfs-owner@vger.kernel.org Received: from bombadil.infradead.org ([198.137.202.9]:41442 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752520AbbBMNYL (ORCPT ); Fri, 13 Feb 2015 08:24:11 -0500 Date: Fri, 13 Feb 2015 05:24:04 -0800 From: Christoph Hellwig To: Anna Schumaker Cc: "J. Bruce Fields" , Trond Myklebust , Linux NFS Mailing List , Thomas D Haynes Subject: Re: [PATCH v2 2/4] NFSD: Add READ_PLUS support for data segments Message-ID: <20150213132404.GA18920@infradead.org> References: <20150205141325.GC4522@infradead.org> <54D394EC.9030902@Netapp.com> <20150205162326.GA18977@infradead.org> <54D39DC2.9060808@Netapp.com> <20150205164832.GB4289@fieldses.org> <54DB7D72.5020001@Netapp.com> <20150211162244.GH25696@fieldses.org> <54DBABE7.9050403@Netapp.com> <54DD0631.8040802@Netapp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <54DD0631.8040802@Netapp.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Thu, Feb 12, 2015 at 02:59:45PM -0500, Anna Schumaker wrote: > Today I learned all about how to use operf to identify where the bottleneck is :). It looks like the problem is in the hole zeroing code on the client side. Is there a better way than memset() to mark a page as all zeros? clear_highpage(), but I don't expect it to make a huge different.