On Apr 5, 2011, at 7:52 AM, Beat Rubischon wrote: > Hi Vincent! > > On 04.04.11 21:16, Vincent Diepeveen wrote: >> latency is superior of quadrics compared to all the infini* stuff. > > Quadrics was great stuff - but it was outperformed once Mellanox > invited > their ConnectX chips. Additional the Quadrics team never got their > PCIe > chips (QSnet III) to fly. Finally the company closed their doors in > may 09. > > I really liked their hard- and software. But the time is over... >
of course there is new great pci-e solutions, yet the price per port there is bigger than entire machine with latest gpu, that's a big problem to make cheap clusters. If you buy a cheap 6 core box of 350 euro then a new generation gpu is 318 euro or so (that's a HD6970). What's node price of the network? >> Of course even the realtime linux kernel is rather crappy there, as >> it locks every action from and to a socket (even RAW/UDP >> communication in fact), so you need a 'hack' of that kernel anyway to >> get faster latencies. > > When talking about Interconnects the kernel is not involved in > communication. Any context switch is avoided to keep the overhead > small. > This basically means a real time kernel isn't needed as it would not > give you any additional benefit. realtime kernel keeps other worst cases down bigtime, especially with respect to scheduling. > > Beat > > -- > \|/ Beat Rubischon <b...@0x1b.ch> > ( 0-0 ) http://www.0x1b.ch/~beat/ > oOO--(_)--OOo--------------------------------------------------- > Meine Erlebnisse, Gedanken und Traeume: http://www.0x1b.ch/blog/ > _______________________________________________ > 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
