Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:20965 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754167AbcH2UCg (ORCPT ); Mon, 29 Aug 2016 16:02:36 -0400 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 9.3 \(3124\)) Subject: Re: [PATCH v2 19/22] xprtrdma: Support larger inline thresholds From: Chuck Lever In-Reply-To: Date: Mon, 29 Aug 2016 16:02:28 -0400 Cc: List Linux RDMA Mailing , Linux NFS Mailing List Message-Id: <741D8723-D193-4F52-826F-807F89DC19C7@oracle.com> References: <20160823174402.13038.84561.stgit@manet.1015granger.net> <20160823175438.13038.1624.stgit@manet.1015granger.net> To: Anna Schumaker Sender: linux-nfs-owner@vger.kernel.org List-ID: > On Aug 29, 2016, at 3:52 PM, Anna Schumaker wrote: > > Hi Chuck, > > On 08/23/2016 01:54 PM, Chuck Lever wrote: >> RPC-over-RDMA Version Two will likely require at least a 4KB inline >> threshold by default. The Version One inline threshold is still 1KB, >> and it's automatically negotiated down to in >> rpcrdma_update_connect_private. > > I'm curious, what is the status of RPCoRDMA v2? There is a personal draft published: https://datatracker.ietf.org/doc/draft-cel-nfsv4-rpcrdma-version-two/ And being discussed actively in the nfsv4 Working Group. The features added in this series are usable with the Linux V1 implementation too; the point being to experiment with these new facilities before we finish RPC-over-RDMA Version Two. > Thanks, > Anna > >> >> The maximum is somewhat arbitrary. There's no fundamental >> architectural limit I'm aware of, but it's good to keep the size of >> Receive buffers reasonable. Now that Send can use a s/g list, a >> Send buffer is only as large as each RPC requires. Receive buffers >> are always the size of the inline threshold, however. >> >> Signed-off-by: Chuck Lever >> --- >> include/linux/sunrpc/xprtrdma.h | 4 ++-- >> net/sunrpc/xprtrdma/transport.c | 4 ++-- >> 2 files changed, 4 insertions(+), 4 deletions(-) >> >> diff --git a/include/linux/sunrpc/xprtrdma.h b/include/linux/sunrpc/xprtrdma.h >> index 39267dc..221b7a2 100644 >> --- a/include/linux/sunrpc/xprtrdma.h >> +++ b/include/linux/sunrpc/xprtrdma.h >> @@ -53,8 +53,8 @@ >> #define RPCRDMA_MAX_SLOT_TABLE (256U) >> >> #define RPCRDMA_MIN_INLINE (1024) /* min inline thresh */ >> -#define RPCRDMA_DEF_INLINE (1024) /* default inline thresh */ >> -#define RPCRDMA_MAX_INLINE (3068) /* max inline thresh */ >> +#define RPCRDMA_DEF_INLINE (4096) /* default inline thresh */ >> +#define RPCRDMA_MAX_INLINE (65536) /* max inline thresh */ >> >> /* Memory registration strategies, by number. >> * This is part of a kernel / user space API. Do not remove. */ >> diff --git a/net/sunrpc/xprtrdma/transport.c b/net/sunrpc/xprtrdma/transport.c >> index 6a358ab..ed5e285 100644 >> --- a/net/sunrpc/xprtrdma/transport.c >> +++ b/net/sunrpc/xprtrdma/transport.c >> @@ -97,7 +97,7 @@ static struct ctl_table xr_tunables_table[] = { >> .data = &xprt_rdma_max_inline_read, >> .maxlen = sizeof(unsigned int), >> .mode = 0644, >> - .proc_handler = proc_dointvec, >> + .proc_handler = proc_dointvec_minmax, >> .extra1 = &min_inline_size, >> .extra2 = &max_inline_size, >> }, >> @@ -106,7 +106,7 @@ static struct ctl_table xr_tunables_table[] = { >> .data = &xprt_rdma_max_inline_write, >> .maxlen = sizeof(unsigned int), >> .mode = 0644, >> - .proc_handler = proc_dointvec, >> + .proc_handler = proc_dointvec_minmax, >> .extra1 = &min_inline_size, >> .extra2 = &max_inline_size, >> }, >> >> -- >> 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-rdma" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Chuck Lever