kern.smp.maxid error on i386 UP [was: powerd / cpufreq question]

[Ian Smith]

On Wed, 20 Apr 2011, Sergey Kandaurov wrote:
 > On 20 April 2011 22:29, Sergey Kandaurov <pluknet at gmail.com> wrote:
 > > On 20 April 2011 21:02, Ian Smith <smithi at nimnet.asn.au> wrote:
[..]
 > >> Very happy to test any patches etc.
 > >>
 > >
 > > Ouch.
 > > Looks like that affects a system with 2 cores as well.
 > > Intel Core2 E7200, 8.2-R i386 SMP:
 > >
 > > kern.smp.forward_signal_enabled: 1
 > > kern.smp.topology: 0
 > > kern.smp.cpus: 2
 > > kern.smp.disabled: 0
 > > kern.smp.active: 1
 > > kern.smp.maxcpus: 32
 > > kern.smp.maxid: 31
 > >
 > > kern.cp_times: 867360 171 429180 70114 170549535 1385294 306 176659 82618
 > > 170270900 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
 > > 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
 > > 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
 > > 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
 > > 0 0 0 0 0 0 0

Ah, well my quick n dirty fix wouldn't even have helped in that case.

 > Perhaps that was so from the begging: the problem is seen also on
 > 6.4 i386 SMP 8 core. Here it was just set to (MAXCPU-1).

Slightly surprising that it went so long unnoticed on SMP boxes, I guess 
nothing actually fell over due to just inefficiency.

 > The buggy mp_maxid was fixed in HEAD with r215009, though not merged.
 > The patch works on my 8.2 Core2 SMP i386 system.
 > 
 > -- 
 > wbr,
 > pluknet

Thanks Sergey.  Confirming the patch works fine on my non-APIC UP i386:

kern.smp.cpus: 1
kern.smp.disabled: 0
kern.smp.active: 0
kern.smp.maxcpus: 32
kern.smp.maxid: 0
kern.cp_times: 1123 2 1414 5621 277346

cheers, Ian