	VMS can quickly boost a processes working set up to WSEXTENT if
pagefaults exceed a certain limit.  This can be a problem since the pages are
never given back, unless the system gets really low on memory.

	Master_blaster is a program which is started as a detached process at
boot time, and cycles every 5 minutes.  It looks at interactive and batch
processes and determines which processes are hogging memory, but are not
actually using it.  Note that the "tuning" that master_blaster does is a major
part of what some of the commercial tuners do, although it has less
intelligence.

	We do not "blast" a process if;

		o It is not interactive or batch
		o Usercode is "SYSTEM"
		o It has more than 1300 pagefaults/5 min.
		o It was recently blasted or at cli prompt (< 210 pages)

	"Blasting" a process is done by issuing a kernel mode AST, which runs
in the context of the target process, and purges their working set to 200
pages.  Each "blasted" process is logged in SYS$MANAGER:MASTER_BLASTER.OUT.

	Although Master_blaster has run well on our systems, there may be
software out there that does not take well to having it's working set trimmed
occasionally.  Master_blaster uses less that .03% CPU time, although may incurr
some CPU usage in the target processes.  Note also that once every 5 minutes
your system will experience a large number of pagefaults as the working sets
are purged, but these should mostly be soft faults.


	To use master_blaster;

		o Copy master_blaster.com and master_blaster.cmd to sys$manager
		o Define a logical SYS$PRIV to point to the directory in which
		  Master_blaster resides, or edit master_blaster.cmd to point
		  to the correct directory
		o Insert "@sys$manager:master_blaster" in your systartup.com
		o You may manually start/restart master_blaster by typing
		  "@sys$manager:master_blaster" interactively (set all privs
		  first)


	The macro subroutine which issues the kernel mode AST is a mofified
version of a program called WSBLASTER, which was authored by Bruce Ellis.

	Although the logic which determines eligible processes has worked
well at our site, I realize that more intelligence or "memory" could help
prevent Master_blaster from causing possible "thrashing" in processes that
really need to have a lot of pages, but don't pagefault much.
