allow the number of disks displayed in the default output
to be controlled.

Update -m description to reflect reality. Kernel dynamic memory tracking
was removed long ago; only pool usage is reported.

Remove reference to Installing and Operating 4.3BSD paper, at present it's not
possible to find a paper titled as such with sections starting with
"Interpreting system activity".
There is a "Monitoring System Performance" section present from the 4.1BSD
Installing and Operating paper up to and including the 4.4BSD paper. The advice
in this section has not aged very well.
From "Installing and Operating 4.3BSD-tahoe UNIX on the VAX":
"Cumulatively on one of our large machines we average about 60-100
context switches and interrupts per second and about 70-120 system calls
per second"

Describe what happens when you run vmstat witout any options aka the first line
of vmstat.

Document vmstat -w -1 is accepted.
via FreeBSD.

Suggest kernhist(9) which is required for vmstat -u and -U
Drop Pp before Bl while here.

branches: 1.20.38; 1.20.44; 1.20.46;
Bump date for uarea swap-out removal.

Remove uarea swap-out functionality:

- Addresses the issue described in PR/38828.
- Some simplification in threading and sleepq subsystems.
- Eliminates pmap_collect() and, as a side note, allows pmap optimisations.
- Eliminates XS_CTL_DATA_ONSTACK in scsipi code.
- Avoids few scans on LWP list and thus potentially long holds of proc_lock.
- Cuts ~1.5k lines of code. Reduces amd64 kernel size by ~4k.
- Removes __SWAP_BROKEN cases.

Tested on x86, mips, acorn32 (thanks <mpumford>) and partly tested on
acorn26 (thanks to <bjh21>).

Discussed on <tech-kern>, reviewed by <ad>.

Move TNF licenses to 2 clause form

branches: 1.17.6;
Add -C option to display pool_cache info, eg:

Pool cache statistics.
Name Spin Full Empty PoolLayer CacheLayer Hit% CpuLayer Hit%
pipepl 0 1 3 385 42862 99.1 985780 95.7
fdescpl 0 0 2 310 31133 99.0 1029620 97.0
cwdipl 0 0 2 310 31227 99.0 1029714 97.0
filepl 0 1 4 680 141415 99.5 24011135 99.4

branches: 1.16.20;
Bump date for -t.

Add a '-t' option to print the contents of the vmtotal structure,
possibly repeatedly.

Sort options. Remove some unnecessary Bk/Ek. Add some commas.

Add a "wide" mode output (selected with -W) to show more information
about memory pools, including pool page size, flags and utilisation.

Uppercase CPU.

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22365, verified by myself.

Actually update man page for change to not show unused pools.

.Nm does not need a dummy argument ("") before punctuation or
for correct formatting of the SYNOPSIS any longer.

- fix section of this manpage; it's 1 not 8.
- use Nm "" instead of just Nm in SYNOPSIS.

New sentence, new line.

Generate <>& symbolically. I'm avoiding .../dist/... directories for now.

- Use -H (instead of -h) to list all hash stats.
- Add '-h hashname' to only list the stats for hashname.
- Add -L to list valid hashes
- Fix up some whitespace

Sort sections, and be consistent in each-vs-every usage at least in this
man page.

- replace -h uvmhist with -u uvmhist, and -H with -U, since uvm history stuff
isn't generally enabled by default, and i wanted -h for something else.
- implement -h, which displays statistics for various kernel hash tables
- add deref_kptr(), which does the hard work of kvm_read() et al
- various minor cleanups

Update the -s description for the uvm era. (It was stuck in the pre-mach
bsd-vax-vm days. :-)

Move vmstat.8 to vmstat.1, since the program lives in /usr/bin now and is
not super-user-only.
Cf. short discussion on tech-userlevel.