Performance issue

Ewan Todd ewan at
Mon May 9 10:21:01 PDT 2005

> 5.3 ships with SMP turned on, which makes lock operations rather 
> expensive on single-processor machines.  4.x does not have SMP
> turned on by default.  Would you be able to re-run your test with
> SMP turned off?

I'm pretty sure there's no SMP in this kernel.

  #cd /usr/src/sys/i386/conf

GENERIC has no SMP in it, but there's a second "GENERIC" kernel conf
called "SMP", which simply says:

  include GENERIC
  options SMP

However, sysctl seems to show smp not active, but not disabled.   Is
that anything to worry about?

  #sysctl -a | grep smp
  kern.smp.maxcpus: 1 0
  kern.smp.disabled: 0
  kern.smp.cpus: 1
  debug.psmpkterrthresh: 2


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