Return-Path: linux-nfs-owner@vger.kernel.org Received: from userp1040.oracle.com ([156.151.31.81]:49868 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752014AbaKJOyg convert rfc822-to-8bit (ORCPT ); Mon, 10 Nov 2014 09:54:36 -0500 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) Subject: Re: [PATCH v2 06/10] xprtrdma: Enable pad optimization From: Chuck Lever In-Reply-To: <5460CD53.1080301@Netapp.com> Date: Mon, 10 Nov 2014 08:54:27 -0600 Cc: linux-rdma@vger.kernel.org, Linux NFS Mailing List Message-Id: <89410A6C-693C-4FB2-A0AB-5698803F3AFC@oracle.com> References: <20141109010328.8806.5861.stgit@manet.1015granger.net> <20141109011453.8806.31817.stgit@manet.1015granger.net> <5460CD53.1080301@Netapp.com> To: Anna Schumaker , "J. Bruce Fields" Sender: linux-nfs-owner@vger.kernel.org List-ID: On Nov 10, 2014, at 8:36 AM, Anna Schumaker wrote: > Hey Chuck, > > > On 11/08/2014 08:14 PM, Chuck Lever wrote: >> The Linux NFS/RDMA server used to reject NFSv3 WRITE requests when >> pad optimization was enabled. That bug was fixed by commit >> e560e3b510d2 ("svcrdma: Add zero padding if the client doesn't send >> it"). > > Do we need to worry about backwards compatibility with servers that don't have this patch? My impression is that we have a window where the server is assumed not to work and thus is not enabled in distributions, and that therefore changes like this are allowed. I could be wrong. Bruce, any guidance on this? In any event, if things break, they break immediately, and the fix is simply to set this feature flag via /proc. > Anna > >> >> We can now enable pad optimization on the client, which helps >> performance and is supported now by both Linux and Solaris servers. >> >> Signed-off-by: Chuck Lever >> --- >> net/sunrpc/xprtrdma/transport.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/net/sunrpc/xprtrdma/transport.c b/net/sunrpc/xprtrdma/transport.c >> index cfe9a81..8ed2576 100644 >> --- a/net/sunrpc/xprtrdma/transport.c >> +++ b/net/sunrpc/xprtrdma/transport.c >> @@ -73,7 +73,7 @@ static unsigned int xprt_rdma_max_inline_read = RPCRDMA_DEF_INLINE; >> static unsigned int xprt_rdma_max_inline_write = RPCRDMA_DEF_INLINE; >> static unsigned int xprt_rdma_inline_write_padding; >> static unsigned int xprt_rdma_memreg_strategy = RPCRDMA_FRMR; >> - int xprt_rdma_pad_optimize = 0; >> + int xprt_rdma_pad_optimize = 1; >> >> #ifdef RPC_DEBUG >> >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > -- > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Chuck Lever chuck[dot]lever[at]oracle[dot]com