There is some add latency due to the 66/64 new encoding, but overall latency is lower than QDR. MPI is below 1us.
Gilad -----Original Message----- From: beowulf-boun...@beowulf.org [mailto:beowulf-boun...@beowulf.org] On Behalf Of Christopher Samuel Sent: Sunday, November 13, 2011 6:42 PM To: beowulf@beowulf.org Subject: Re: [Beowulf] building Infiniband 4x cluster questions -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi Gilad, On 08/11/11 12:53, Gilad Shainer wrote: > The latency numbers are more or less the same between the IB vendors > on SDR, DDR and QDR. Mellanox is the only vendor with FDR IB for now, > and with PCIe 3.0 latency are below 1us (RDMA much below...). Is that for an MPI message ? I'd heard that FDR might have higher latencies due to the coding changes that were happening - is this not the case ? cheers, Chris - -- Christopher Samuel - Senior Systems Administrator VLSCI - Victorian Life Sciences Computation Initiative Email: sam...@unimelb.edu.au Phone: +61 (0)3 903 55545 http://www.vlsci.unimelb.edu.au/ -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk7Af7MACgkQO2KABBYQAh8HyQCdG3AUK1k6QmyRd7SueQLp3MHZ 1wsAn3VxYqclLdQcqBv5yxd4LLvhsiLv =Hf0h -----END PGP SIGNATURE----- _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org sponsored by Penguin Computing To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org sponsored by Penguin Computing To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
