the NTP kernel PLL is disabled, and acquire_timer0() is enabled, thus
opening the door for microtime() (and hence gettimeofday()) to return
bogus timestamps. This option is necessary for the `pca' driver to
work, but is implemented to underscore the fact that accurate timekeeping
and the `pca' driver are incompatible at present. If someone writes a version
of microtime() that works when the `pca' driver is being used, this can get
junked.
1) check va before clearing the page clean flag. Not doing so was
causing the vnode pager error 5 messages when paging from
NFS. (pmap.c)
2) put back interrupt protection in idle_loop. Bruce didn't think
it was necessary, John insists that it is (and I agree). (swtch.s)
3) various improvements to the clustering code (vm_machdep.c). It's
now enabled/used by default.
4) bad disk blocks are now handled properly when doing clustered IOs.
(wd.c, vm_machdep.c)
5) bogus bad block handling fixed in wd.c.
6) algorithm improvements to the pageout/pagescan daemons. It's amazing
how well 4MB machines work now.
1) Removed all instances of disable_intr()/enable_intr() and changed
them back to splimp/splx. The previous method was done to improve
the performance, but Bruces recent changes to inline spl* have
made this unnecessary.
2) Cleaned up vm_machdep.c considerably. Probably fixed a few bugs, too.
3) Added a new mechanism for collecting page statistics - now done by
a new system process "pagescan". Previously this was done by the
pageout daemon, but this proved to be impractical.
4) Improved the page usage statistics gathering mechanism - performance is
much improved in small memory machines.
5) Modified mbuf.h to enable the support for an external free routine when
using mbuf clusters. Added appropriate glue in various places to
allow this to work.
6) Adapted a suggested change to the NFS code from Yuval Yurom to take
advantage of #5.
7) Added fault/swap statistics support.
finally have the f**king documentation!):
1) Changed all the numeric register offsets to symbolic ones (it should
have been this way originally).
2) If 16 bit, disable the shared memory when not using it. Apparantly
switching between 8/16bit mode makes the Ultra unhappy unless
this is done (i.e. it trashes the bus).
