Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:39173 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932443AbbGJO7w convert rfc822-to-8bit (ORCPT ); Fri, 10 Jul 2015 10:59:52 -0400 Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) Subject: Re: [PATCH v1 5/5] svcrdma: Boost NFS READ/WRITE payload size maximum From: Chuck Lever In-Reply-To: <20150710141814.GA31121@fieldses.org> Date: Fri, 10 Jul 2015 10:59:48 -0400 Cc: Linux NFS Mailing List , linux-rdma@vger.kernel.org Message-Id: <11D08769-F6EB-4696-8910-8B207B20CC10@oracle.com> References: <20150709204230.8481.45457.stgit@klimt.1015granger.net> <20150709204546.8481.65857.stgit@klimt.1015granger.net> <20150710141814.GA31121@fieldses.org> To: "J. Bruce Fields" Sender: linux-nfs-owner@vger.kernel.org List-ID: On Jul 10, 2015, at 10:18 AM, bfields@fieldses.org wrote: > On Thu, Jul 09, 2015 at 04:45:47PM -0400, Chuck Lever wrote: >> Increased to 1 megabyte. > > Why not more or less? > > Why do we even have this constant, why shouldn't we just use > RPCSVC_MAXPAYLOAD? The payload size maximum for RDMA is based on RPCRDMA_MAX_SVC_SEGS. We could reverse the relationship and make RPCRDMA_MAX_SVC_SEGS based on RPCSVC_MAXPAYLOAD divided by the platform?s page size. > --b. > >> >> Signed-off-by: Chuck Lever >> --- >> >> include/linux/sunrpc/svc_rdma.h | 2 +- >> 1 files changed, 1 insertions(+), 1 deletions(-) >> >> diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h >> index 13af61b..1bca6dd 100644 >> --- a/include/linux/sunrpc/svc_rdma.h >> +++ b/include/linux/sunrpc/svc_rdma.h >> @@ -172,7 +172,7 @@ struct svcxprt_rdma { >> #define RDMAXPRT_SQ_PENDING 2 >> #define RDMAXPRT_CONN_PENDING 3 >> >> -#define RPCRDMA_MAX_SVC_SEGS (64) /* server max scatter/gather */ >> +#define RPCRDMA_MAX_SVC_SEGS (256) /* server max scatter/gather */ >> #if RPCSVC_MAXPAYLOAD < (RPCRDMA_MAX_SVC_SEGS << PAGE_SHIFT) >> #define RPCRDMA_MAXPAYLOAD RPCSVC_MAXPAYLOAD >> #else >> >> -- >> 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