Chuck Silvers wrote:

> On Thu, Mar 10, 2005 at 10:24:22AM +1100, Simon Burge wrote:
> > Just for kicks, here's some times with a -current kernel from sources
> > around March 7th.  This is a trimmed down kernel with no IPV6,
> > filesystems I don't use, etc (same as the above 2.0F benchmarks).  When
> > the kernel boots, I see:
> > 
> > 	NetBSD 2.99.16 (PC532) #65: Thu Mar 10 08:36:15 EST 2005
> > 	total memory = 8192 KB
> > 	avail memory = 6992 KB
> > 
> > time (real)                  vm.bufmem_hiwater vm.{anon,exec,file}{min,max}
> > 7:44.74 43.3%   0+0k 101+39io 44309pf+1w  524288  {{10,95},{ 5,30},{10,50}}
> > 4:43.54 43.3%   0+0k   5+26io 17627pf+1w  524288  {{10,95},{ 5,10},{ 5,15}}
> > 2:53.01 53.1%   0+0k   4+24io  7883pf+1w  131072  {{10,95},{ 5,10},{ 5,15}}
> > 2:14.59 60.2%   0+0k   4+24io  4552pf+1w  131072  {{10,95},{ 5,10},{ 0, 5}}
> > 1:56.30 65.7%   0+0k   4+24io  3404pf+1w  131072  {{10,95},{ 5,10},{ 0, 1}}
> > 1:54.14 66.5%   0+0k   4+24io  3261pf+1w  131072  {{10,95},{ 0,10},{ 0, 1}}
> > 1:51.39 67.9%   0+0k   4+23io  3209pf+1w  131072  {{10,80},{ 0,10},{ 0, 1}}
> > 
> > Note that the user time component of was a relatively constant 60 to 61
> > seconds, and system time was 139 seconds in the first down to 15 seconds
> > in the last test.
> > 
> > Compare those times with a trimmed down kernel against a GENERIC kernel
> > (6284 KB free at boot) for the vm tunables with the fastest time above.
> > 
> > time (real)                  vm.bufmem_hiwater vm.{anon,exec,file}{min,max}
> > 8:55.57 44.2%  0+0k 3+24io 52780pf+1w  131072  {{10,80},{ 0,10},{ 0, 1}}
> > 
> > And then compare that with a 1.5X GENERIC kernel (6220KB free):
> > 
> > 55.189u  20.468s  2:06.78 59.6% 0+0k 71+63io  5364pf+0w
> 
> so basically, the extra ~700k makes a huge difference.  this benchmark just
> barely fits in memory.  I doubt there are any sysctl settings that would
> allow a GENERIC -current kernel to get a 2 minute run.

I keep meaning to play with more tests, but I just haven't had the time
recently.

The main sticking point from my POV is that my pc532 with a 1.5X GENERIC
without any sysctl knobs and reporting "avail mem 6220 KB" at boot
builds machdep.o in around 2mins.  An untuned -current GENERIC gets
something silly like 40+ minutes.  The only way I can get close to 2min
with -current is playing around with trimmed down kernels that report
nearly 7MB free then playing around with sysctl knobs until I find some
combination that "works".

Note too that userland has been constant since I first starting doing
these tests, primarily because it's too hard to build a recent userland
:-/

Simon.
--
Simon Burge                            <simonb@wasabisystems.com>
NetBSD Support and Service:         http://www.wasabisystems.com/