Performance of 4.x vs 5.x (Re: Lifetime of FreeBSD branches)

Freddie Cash fcash at
Tue May 24 09:22:48 PDT 2005

On May 23, 2005 02:31 pm, Kris Kennaway wrote:
> On Mon, May 23, 2005 at 11:21:13PM +0200, Matthias Buelow wrote:
> > Another thing might be that interactive response time seems to be
> > worse. While I (or rather ports) unpack the firefox/thunderbird
> > source, the machine is pretty much bogged down (mouse cursor jumps
> > around, audio stutters...).  Haven't seen that on FreeBSD since the
> > 386 days.

> I don't run FreeBSD on my desktop machines so I haven't seen this
> myself.  One obvious guess is that it's due to VFS being under Giant,
> which causes lots of contention with other subsystems that also
> require Giant, and therefore introduces latency.  If so, you'd see a
> substantial performance improvement on 6.0 with debug.mpsafevfs=1.
> This option isn't yet ready for production use (especially on SMP
> machines) since it still contains bugs, but it would be interesting if
> someone who sees this problem could test it on 6.0.

> Any takers?

I haven't run any actual benchmarks, but I have 6-CURRENT (May 20) on my 
2.4 GHz Celeron laptop (1 GB RAM), a Toshiba Satellite A60.  Installing 
ports, even large ones like firefox, thunderbird,, java, 
xorg, or kde (that take a long time to uncompress and/or compile) doesn't 
affect my usage of the computer, even when in KDE.

The laptop has an ATI IXP chipset, which means the HD is detected and run 
as a generic UDMA33 device.  The kernel is using the 4BSD scheduler with 
PREEMPTION enabled, all debugging hints disabled, and all the mpsafe 
sysctls enabled.

The only time I see any kind of slowdown or stuttering when in X is if I 
have multiple compiles running in the background (usually a buildworld and 
a portupgrade session) without using nice.  If doing a single port install 
(no nice values) in the background, I don't notice it.  The only other app 
that is slow on this system is Firefox (but that's slow on every system 
I've tried, FreeBSD, Linux, and Windows), which is why I tend to use 
Konqueror as much as possible.

If anyone wants actual benchmark results or timing tests, they'll have to 
let me know what to run, as I've never done any benchmarking before.  All 
I can say is that I don't notice any slowdowns or stuttering or anything 
like that on this system.  And it's my do-everything workstation (plugged 
into a 21" monitor, USB mouse and keyboard when at work).

Freddie Cash
fcash at

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