Contributed by Dengue on from the it's-lots-faster-send-ram-dept dept.
OpenBSD/macppc has recently received a significant speed improvement. The pmap (MMU) code has been replaced and this newer, more efficient, code allows for much faster process startup and exit.
These results are from lmbench 1.0 (available in ports)Processor, Processes - times in microseconds -------------------------------------------- Host OS Mhz Null Null Simple /bin/sh Mmap 2-proc 8-proc Syscall Process Process Process lat ctxsw ctxsw --------- ------------- ---- ------- ------- ------- ------- ---- ------ ------ speedy OpenBSD 3.0 736 1 7K 15K 35K 2827 1 1 speedy.3 OpenBSD 3.0 736 1 1K 5K 9K 431 1 1speedy is a PowerMac G4 733MHz, only the kernel was replaced between the tests.Notice that mmap latency is now 15% of what it used to be, a 85% improvement. Process startup sees this same advantage on small tests, however on processes which do more, this speedup is not as noticeable. Since many of the activities performed on unix machines typically involve startup of one (or several) processes, the machine has the feeling of being faster.
Of course the benchmark which most hackers are interested in, this improvement changes a make build which used to take 2:50 to now take 1:55, a 33% speedup.
This change does not change how fast a CPU bound process runs on the machine, it primarily only affects mmap and fork/exit speeds.
One of the issues with this code is it is exposing problems with large memory machines. Recently (before this change) a report that OpenBSD would not boot on a 1.25GB machine, and with this change there are problems with more than 1GB of memory. This will likely only change if 512MB memory modules find their way to the macppc developers.
---Dale Rahn drahn@openbsd.org
(Comments are closed)
By Joshua () on
it strictly as a server, I imagine I would use OSX
instead. And for a server, wouldn't cheaper off-
the-shelf ix86 stuff be a wiser choice?...
Anyhow, I was wondering if it is possible to run
some sort of UNIX, preferrably a *BSD, on an old
Apple Performa 6400 (603e). It would be cool as a
UNIX box / firewall - otherwise, it's ::sigh::
only good for OS9.
By Anonymous Coward () on
Modern ones are out of reach for me and many. There are other choices (NetBSD, Yellow Doze, blah), some even very good, but NOT good enough if you're used to OpenBSD.
By Peter Hessler () spambox@theapt.org on http://www.sfobug.org