On 2007-04-27 04:38, Matthew Dillon wrote:
[snip some really cool stuff]
The 64 bit sysids will be unique, which is a very simple mechanism...
each cpu just initializes a 64 bit sysid to a shifted timestamp on
boot, and then increments it by <ncpus> to 'allocate' a sysid. You
can't get much simpler then that. I don't think it would be possible
to overflow a 64 bit counter, even incrementing by ncpus, without at
least a hundred years of uptime and I'm just not worried about a
hundred years of uptime for a single host.
Since most of it is a bit above me I'll ask about what I can understand.
While I agree with you that 64 will probably suffice I also know of
someone who thought that 640k would be enough memory and another who
though that the world would never need more than one super-computer. But
if I understand things correctly it will be fairly easy to upgrade to
128 (or whatever) bits in the future should that be necessary since the
sysid is centralized to sysreg, the SYSLINK protocol and whatever uses
it. So basically all it would take is a change of type in a few places
and a recompile right?
--
Erik Wikström
