🚀 go-pugleaf

	I'd first like to thank everybody for their input on this, there
didn't seem to be much of a consensus on this, so we're goning to handle it
like this:

	First a quick note: we're using a RS/6000 and we expect the matrix
to be around 500+ MB.

	Our game plan is to mmap a file, map the matrix to that address
space and fork off processes to handle chunks of it using MP style code.

	Our hope is that while some of the processes are blocked, waiting
for the parts of the matrix that they've touched to be paged in, other
processes will be able to continue crunching on pages that are curently in
core.

	We can (and will) take over the machine to run this, but are
wondering what the ratio should be between:

	Demand: The combined working set of the running processes. ( = Size
of each block * number of blocks active at a time for a process * total
number of processes)

	and Supply: Total system physical memory. (64 MB minus some amount
for the OS and per process overhead).

	It seems as though Demand should be about equal to Supply, but we'd
like to hear of any studies on this.

	It might prove to be useful to overcommit a little (for some sort of
read-ahead?) or undercommit by some factor (to provide "extra caching").
At the moment we're tempted to just provide args for block-size and number
of processes and test it out that way.
--
	Henry J. Cobb	hcobb@fly2.berkeley.edu	SFB Tyrant
	"A const pointer is a steady reference,
	while a pointer to const is a pledge not to tinker."