I'm saying that's what the definition of a Clos network is, and that's the only situation in which it's "non-blocking".
People buy clusters with all kinds of network configurations. On Thu, Feb 06, 2014 at 09:51:10PM -0600, Alan Louis Scheinine wrote: > When I wrote "the number of nonblocking connections is typically > much less than the number of nodes" I had in mind the telephone > network (in the age of copper wires). Are you sure that "1/2 the > nodes can make a single call to the other 1/2 of the nodes" is > typical of a computer interconnect? I thought that the typical > cross-sectional bandwidth was less, or am I mistaken? > Alan Scheinine > > Greg Lindahl wrote: >> In the usual Clos network, 1/2 of the nodes can make a single call to >> the other 1/2 of the nodes. That's what's non-blocking. Nothing else >> is. Running any real code, every node talks to more than one other >> node, and the network is not non-blocking. >> >> It makes perfect sense in a telephone network. In the real world, a >> Clos network is good but not non-blocking. >> >> On Wed, Feb 05, 2014 at 06:31:11PM -0600, Alan Louis Scheinine wrote: >>> Clos is non-blocking up to a certain number of completed connections. >>> The number of nonblocking connections is typically much less than >>> the number of nodes for which the Clos network provides service. >>> Anybody can make a telephone call to anybody else, up until the >>> maximum number of completed connections is reached. >>>> At least that is what Chuck Seitz drove into our heads whenever we said >>>> that a Clos was non-blocking. :-) >>>> >>>> Scott >>>> >>> -- >>> >>> Alan Scheinine >>> 200 Georgann Dr., Apt. E6 >>> Vicksburg, MS 39180 >>> >>> Email: alschein...@tuffmail.us >>> Mobile phone: 225 288 4176 >>> >>> http://www.flickr.com/photos/ascheinine >>> _______________________________________________ >>> 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 > > > -- > > Alan Scheinine > 200 Georgann Dr., Apt. E6 > Vicksburg, MS 39180 > > Email: alschein...@tuffmail.us > Mobile phone: 225 288 4176 > > http://www.flickr.com/photos/ascheinine _______________________________________________ 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
