Instead of pulling in process tables itself, ProcFS now queries the
MIB service for process information. This reduces ProcFS's memory
usage by about 1MB. The change does have two negative consequences.
First, getting all the original /proc/<pid>/psinfo fields filled in
would take a lot of extra effort. Since the only program that uses
those files at all is mtop(1), we reformat psinfo to expose only the
information used by mtop(1). This means that with this patch, older
copies of MINIX3 ps and top will cease to work.
Second, since both MIB and ProcFS update their own view of the
process list only once per clock tick, ProcFS' view may now be
outdated by up to two clock ticks. This is unlikely to pose a
problem in practice.
Change-Id: Iaa6b60450c8fb52d092962394d33d08bd638bc01
Due to differences in (mainly) measuring and accumulating CPU times,
the two top programs end up serving different purposes: the NetBSD
top is a system administration tool, while the MINIX3 top (now mtop)
is a performance debugging tool. Therefore, we keep both.
The newly imported BSD top has a few MINIX3-specific changes. CPU
statistics separate system time from kernel time, rather than kernel
time from time spent on handling interrupts. Memory statistics show
numbers that are currently relevant for MINIX3. Swap statistics are
disabled entirely. All of these changes effectively bring it closer
to how mtop already worked as well.
Change-Id: I9611917cb03e164ddf012c5def6da0e7fede826d
