RE: [myrinet] Synronization?

> Do any one know how to manage the event/step syncronization in parallel
> computer system which use Myrinet?

The Cray T3E had a sophisticated mechanism for synchronizing clocks across a
cluster connected with a high-speed interconnect. Maybe it is described in a
paper somewhere. The NTP protocol used by workstations has time constants in
it (so I'm told by people who have looked) that make it useless for
sub-millisecond synchronization. However, it probably wouldn't be hard to
write a simple program to compute the offset of your local clock from a
remote one. NTP is complex because it handles jitter and drift. But with
Myrinet, the round trip time is often stable if the other end is nearly
idle. So you should be able to synchronize within a fraction of a round-trip
time, which may be much better than any clock on your CPU.

-- greg