From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: [PATCH v3 03/13] Attach/detach SoftiWarp to/from network and RDMA subsystem Date: Tue, 23 Jan 2018 09:43:16 -0700 Message-ID: <20180123164316.GC30670@ziepe.ca> References: <20180114223603.19961-1-bmt@zurich.ibm.com> <20180114223603.19961-4-bmt@zurich.ibm.com> <00ff01d39467$f1f31b60$d5d95220$@opengridcomputing.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <00ff01d39467$f1f31b60$d5d95220$@opengridcomputing.com> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Steve Wise Cc: 'Bernard Metzler' , linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-rdma@vger.kernel.org On Tue, Jan 23, 2018 at 10:33:48AM -0600, Steve Wise wrote: > > +/* Restrict usage of GSO, if hardware peer iwarp is unable to process > > + * large packets. gso_seg_limit = 1 lets siw send only packets up to > > + * one real MTU in size, but severly limits maximum bandwidth. > > + * gso_seg_limit = 0 makes use of GSO (and more than doubles throughput > > + * for large transfers). > > + */ > > +const int gso_seg_limit; > > + > > The GSO configuration needs to default to enable interoperation with all > vendors (and comply with the RFCs). So make it 1 please. The thing we call GSO in the netstack should be totally transparent on the wire, so at the very least this needs some additional elaboration. > Jason, would configfs be a reasonable way to allow tweaking these globals? Why would we ever even bother to support a mode that is non-conformant on the wire? Just remove it.. Jason -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html