<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: Arial; font-size: 12pt; color: #000000'><br>Mark Hahn wrote: <br><br>>Regardless of how tight the seastar per-hop latency is,<br>>IB has 2.5x the per-hop fanout (2or 3 outgoing 9.6 GB links <br>>versus 18 outgoing 4 GB/s links). higher radix means an <br>>advantage that increases with size.<div><br></div><div>Doesn't this assume worst case all-to-all type communication</div><div>patterns. If you are just trading ghost cell data with your neighbors</div><div>and you have placed your job smartly on the torus the fan out</div><div>advantage mentioned is irrelevant. No?</div><div><br></div><div>rbw<br>_______________________________________________<br>Beowulf mailing list, Beowulf@beowulf.org sponsored by Penguin Computing<br>To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf<br></div></div></body></html>