Re: Larger dev_t

Jamie Lokier
2001-03-25T17:02:10Z

Mitchell Blank Jr wrote:
> Wichert Akkerman wrote:
> > You are just delaying the problem then, at some point your uptime will
> > be large enough that you have run through all 64bit pids for example.
>
> 64 bits is enough to fork 1 million processes per second for over
> 500,000 years. I think that's putting the problem off far enough.

The year is 2006. IBM's latest supercluster has 1000 boxes, each with 4
x 8-way SMT processors running at 1THz. Dense optical interconnect
provides NUMA-style cache coherency, and the entire system runs like a
giant SMP box (using kernel data structure replication). Each active
thread is able to clone() 500,000,000 threads per second, in a pid space
shared throughout the cluster.

A virus arrives containing while(1){clone();}

Engineers observe pid wraparound approximately 2 weeks later :-)

-- Jamie