NetBSD/distrib/notes/pmax/whatis

This is the third public release of NetBSD for the DECstation and
DECsystem family of computers.  

This release includes support for either mips1 (r2000, r3000) and
mips3 (r4000, r4400, r4600) CPUs. mips1 and mips3 support can be
configured into a single kernel.  NetBSD 1.3 can be installed onto
DECstation 5000/50, 5000/150, 5000/260, or 5900 models, as well as all
previously-supported hardware.

Though stable NetBSD/pmax snapshots with shared-library support have
been available for over a year, this is the first full NetBSD/pmax
release to ship with ELF shared libraries.  Much of the user-space
support for this is due to work by Per Fogelstrom (pefo@OpenBSD.ORG)
and ported to NetBSD by Manuel Bouyer.

Ultrix emulation for Internet applications is improved over NetBSD
1.2.  The Ultrix `ifconfig' command and multicast applications now
work in Ultrix compatibility mode.  A ecoff-format NetBSD kernel in an
Ultrix root filesysstem should boot multi-user, though this is not
recommended as an installation method.

A bug in mips interrupt handling from 4.4BSD, which could cause
`remrunque' panics under heavy load in both NetBSD prior to 1.2E and
OpenBSD, is fixed in this release.

There are yet more enhancements for the 4.4bsd-Lite/pmax SCSI drivers,
which now correctly probes newer, faster, SCSI-2 disks, and handles
large transfers (up to 64K) on 3100s.  Intermediate copies of disk I/O
on IOASIC-based machines are eliminated, yielding a modest improvement
on old disks like the rz25, and a bigger improvement on faster disks.

Kernel performance tuning includes lower system call overhead, a
faster bcopy() routine, faster IP checksumming code, and other
imrprovemnts. These combine to show a dramatic (e.g., 1.5x-2.5x)
improvement on microbenchmarks like the lmbench suite, and a modest
improvement on larger benchmarks like kernel builds.