From mboxrd@z Thu Jan 1 00:00:00 1970 From: Amir Vadai Subject: Re: Socket Direct Protocol: help (2) Date: Wed, 14 Apr 2010 17:31:47 +0300 Message-ID: <4BC5D1D3.3020004@mellanox.co.il> References: <13381_1271060138_o3C8FUH8013968_2977669.1271060085255.SLOX.WebMail.wwwrun@imap.lnl.infn.it> <1246722.1271082830120.SLOX.WebMail.wwwrun@imap.lnl.infn.it> <2EFBCAEF10980645BBCFB605689E08E9047C7402DA@azsmsx506.amr.corp.intel.com> <4BC49E2B.3000804@opengridcomputing.com> <2EFBCAEF10980645BBCFB605689E08E9047C7405A0@azsmsx506.amr.corp.intel.com> <4BC4D22A.6020700@opengridcomputing.com> <2EFBCAEF10980645BBCFB605689E08E9047C7405E9@azsmsx506.amr.corp.intel.com> <7037536.1271235105513.SLOX.WebMail.wwwrun@imap.lnl.infn.it> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <7037536.1271235105513.SLOX.WebMail.wwwrun@imap.lnl.infn.it> Sender: linux-kernel-owner@vger.kernel.org To: Andrea Gozzelino Cc: "Tung, Chien Tin" , Steve Wise , "linux-kernel@vger.kernel.org" , "linux-rdma@vger.kernel.org" , "rolandd@cisco.com" , "peterz@infradead.org" , "pavel@ucw.cz" , "mingo@elte.hu" , Eric B Munson List-Id: linux-rdma@vger.kernel.org Hi, FMR are being used only in a special mode called ZCopy. You could disable this mode by setting the module paramter sdp_zcopy_thresh to 0, or by issuing: # echo 0 > /sys/module/ib_sdp/parameters/sdp_zcopy_thresh This means that you won't get the benefits of Zero-copy. - Amir On 04/14/2010 11:51 AM, Andrea Gozzelino wrote: > On Apr 13, 2010 10:22 PM, "Tung, Chien Tin" > wrote: > > >>>>> Chien, does the NE020 support FMRs? I looked at the nes ofed-1.5 >>>>> code >>>>> and it appears to do nothing in the map_phys_fmr functions. >>>>> >>>>> >>>> We never implemented map_phys_fmr. Is it relevant to the # of SGEs? >>>> >>>> >>> No, but SDP uses FMRs. I don't think it will run without FMR support. >>> >>> >> >> Good to know. Thanks. >> >> Chien >> >> >> > Hi Steve and Chien, > > I understand that NE020 cards have problem with SDP connected with > map_phy_fmr (FMR stands for Fast Memory Region). > Is it possible to solve/fix this point? > If yes, have you an idea about the time that is necessary to code > development/build? > If no, can you suggest me a card that supports SDP protocol? > > I work on NE020 cards from February 2010 for an INFN experimental > proposal, called REDIGO (Read out at 10 Gbits/s), about the data > acquisition and movement systems. The covergence of storage protocols > around 10 Gigabits/s Ethernet protocols shows that one way could be the > Remote Direct Memory Access (RDMA). The goals are the investigations of > latency time, the throughput, the buffer size schemes and finally the > global event building bandwidth. > > Do you know if NE020 cards have problems with librdma (RDMA procedures, > in general) and / or with MPI versions? > > Thank you very much, > Andrea > > Andrea Gozzelino > > INFN - Laboratori Nazionali di Legnaro (LNL) > Viale dell'Universita' 2 > I-35020 - Legnaro (PD)- ITALIA > Tel: +39 049 8068346 > Fax: +39 049 641925 > Mail: andrea.gozzelino@lnl.infn.it > > -- > 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 >