FreeBSD 7.0-RELEASE: Can I specify the maximum number of cores that kernel can recognize ?

[Hattori, Shigehiro]

Hi,

I try to measure Bind caching name server's multi threading performance on
FreeBSD 7 , like below.

--
# of cores    query/second
1                 xx
2                 xx
4                 xx
6                 xx
8                 xx
--

My testing machine has 8 cores. ( quad core * 2 )

I'd like to specify the maximum # of cores that kernel can recognize.
Can I specify the maximum # of cores with boot parameters or something ?

I've already done Bind multi threading performance test on Linux ( CentOS5 )
In case of CentOS5 , I specified maximum # of cores with grub.conf　"maxcpus=1
or 2 or 4 or ..."

# cat /etc/grub.conf
title CentOS (2.6.18-53.1.21.el5PAE)
        root (hd0,1)
        kernel /boot/vmlinuz-2.6.18-53.1.21.el5PAE ro root=LABEL=/ rhgb
quiet maxcpus=6
        initrd /boot/initrd-2.6.18-53.1.21.el5PAE.img
#

The following is the results I did on CentOS5 ( kernel:
2.6.18-53.1.21.el5 ).

-- Bind 9.4.2 caching name server on CentOS5
# of cores    query/second    CPU ( named )
1                 3578                99.9
2                 5070                196
4                 6608                362
6                 9042                527
8                 10552               678
--

- Bind's machine spec

CPU: Intel Xeon E5346  2.3GH ( quad core * 2 )
Memory: 4GB
Bind 9.4.2
Cache size: 1400MB
Max recursive clients: 50000

- Traffic generetor: queryperf
Query list: all queries are uniq ( that means "No answer in the cache" )

Best regards,
Shigehiro