Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753871AbbFIQFQ (ORCPT ); Tue, 9 Jun 2015 12:05:16 -0400 Received: from mail-ig0-f178.google.com ([209.85.213.178]:33717 "EHLO mail-ig0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752393AbbFIQFH (ORCPT ); Tue, 9 Jun 2015 12:05:07 -0400 MIME-Version: 1.0 In-Reply-To: References: From: Bjorn Helgaas Date: Tue, 9 Jun 2015 11:04:46 -0500 Message-ID: Subject: Re: [PATCH v3 18/18] NTB: Increase transport MTU to 64k from 16k To: Allen Hubbe Cc: linux-ntb@googlegroups.com, "linux-kernel@vger.kernel.org" , "linux-pci@vger.kernel.org" , Jon Mason , Dave Jiang Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1696 Lines: 43 On Tue, Jun 9, 2015 at 4:44 AM, Allen Hubbe wrote: > From: Dave Jiang > > Benchmarking showed significant performance increase going from MTU size > of 64k from 16k. Changing the default. This changelog doesn't parse. I think you mean "going from MTU size 16k to 64k." The original value was 0x401e (16k + 0x1e), and the new value is exactly 64k. Please include a note about what that extra 0x1e was for and why it isn't needed in the new value. > Signed-off-by: Dave Jiang > --- > drivers/ntb/ntb_transport.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c > index ea237aeca28c..c87bc0cbd607 100644 > --- a/drivers/ntb/ntb_transport.c > +++ b/drivers/ntb/ntb_transport.c > @@ -76,7 +76,7 @@ static unsigned long max_mw_size; > module_param(max_mw_size, ulong, 0644); > MODULE_PARM_DESC(max_mw_size, "Limit size of large memory windows"); > > -static unsigned int transport_mtu = 0x401E; > +static unsigned int transport_mtu = 0x10000; > module_param(transport_mtu, uint, 0644); > MODULE_PARM_DESC(transport_mtu, "Maximum size of NTB transport packets"); > > -- > 2.4.0.rc0.43.gcf8a8c6 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" 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-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/