Re: cluster list

["Albert D. Cahalan" <acahalan@cs.uml.edu>]

> How would these hardware differences affect eg. a lock
> manager or a global filesystem ?

I'd have to see the design of course, but...

On systems with reliable broadcast mail, you can do some sort of
a barrier operation across the whole cluster. It is trivial.
(meaning a system where one node can grab the whole interconnect)

On an Ethernet system, two nodes could initiate a broadcast at
the same time. With packet losses and clock uncertainty, one can
not be sure what happened first.

On an Ethernet system, it is very important to group things together.
Packets have high overhead. On a large SMP or NUMA system, grouping
things together would increase latency for no good reason.

I think a global filesystem changes when any node or device can
write directly to any other node or device, without any queuing
on a network card. The node that wants to read data can reserve
space for it, and tell the sender what physical memory address
should be used.


Linux-cluster: generic cluster infrastructure for Linux
Archive:       http://mail.nl.linux.org/linux-cluster/