From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ido Shamai Subject: Re: perftest question Date: Wed, 18 May 2011 09:57:06 +0300 Message-ID: <4DD36DC2.2090303@dev.mellanox.co.il> References: <20110517131910.3dw9cgbfj4ck04cw@celticblues.com> <4DD2CF58.5080806@dev.mellanox.co.il> <20110517135306.zxkyatjh2oows8co@celticblues.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20110517135306.zxkyatjh2oows8co-x2spCj9RiN0z5UmgcLIfJQ@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: ib-x2spCj9RiN0z5UmgcLIfJQ@public.gmane.org Cc: linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-rdma@vger.kernel.org On 5/17/2011 10:53 PM, ib-x2spCj9RiN0z5UmgcLIfJQ@public.gmane.org wrote: > Ok. Thanks for the information. > > Is there any particular advantage of using CM over TCP for this information (LID or GID, Qp num, PSN, RKey and the address of the writing buffer)? > > Is ib_write_bw an example of RDMA write / RD? > > E > Except of the iWarp support Steve mentioned I think the rdma_cm has an advantage because it does not required an additional Ethernet connection to the machines. the test has all it's need. ib_write_bw is an excellent example of RDMA write with a lot of feature. it can run on RC and UC (no RD). If you want to view a code of RDMA write, look at ib_write_bw. Ido > > Quoting Ido Shamai : > >> Those are actually the same tests, from an IB point of view. >> >> the difference between them is that ib_write_bw passes the arguments >> that need to be known to other side ( LID or GID, Qp num, PSN, RKey and >> the address of the writing buffer) before post_sending, >> >> through TCP connection (using sockets) and the rdma_bw uses the rdma_cm >> module , which sends those arguments through the IB wire and the SM. >> >> rdma_cm is not updated with all the features ib_write_bw have. I will >> work on this test shortly >> >> Ido >> >> >> On 5/17/2011 10:19 PM, ib-x2spCj9RiN0z5UmgcLIfJQ@public.gmane.org wrote: >>> Just downloaded a snapshot of the perftests. In the README under "Test Descriptions" it says: >>> >>> rdma_bw.c streaming BW test with RDMA write transactions >>> >>> and >>> >>> write_bw.c BW test with RDMA write transactions >>> >>> What is the difference between rdma_bw and write_bw? I see that the rdma_bw description contains "streaming" where as write_bw description does not... but I am not sure I understand what that means? >>> >>> E >>> >>> -- >>> 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 >>> > > > > -- > 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 > -- 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