6.0 Stable on 8 Core AMD Opteron scalability. (perf stat)

[Joseph Koshy]

jk> which benchmark?
a> jakarta jmeter with customly builded test plan for PHPBB

No Java on my system :(.

a> bge0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu  1500
...
a>       media: Ethernet autoselect (none)
a>       status: no carrier

It wasn't clear if you were running over a localhost-only
benchmark.  If not, did your network card manage
to negotiate full-duplex mode?

a> See below...
a> PS: maybe httpd wait for log write?
a> $ vmstat 2 99999
...

[vmstat output]
a> 66 0 0 1375484 14423592 34484   0   0   0 31638   0  15   0 3503
259224 109744 53 21 26

Ok, no memory pressure, a large system-call rate and a large
number of context switches per second.

a>  8634 mysql     111  76    0   367M   122M RUN    7   0:52  0.00% mysqld

This process looks suspicious.  Please check if you are
running MySQL with an appropriate configuration (my-huge.cnf?).
http://wikitest.freebsd.org/moin.cgi/MySQL has more
hints about tuning MySQL.  Does changing sysctl
kern.timecounter help?

I would appreciate a hwpmc profile of your system under
this load.

Step 1  # kldload hwpmc
     2  # pmcstat -S k8-bu-cpu-clk-unhalted -O /tmp/logfile
          [for less than a  minute]
     3  ^C [kill pmcstat]
     4  # pmcstat -R /tmp/logfile -g
     5  # [for each foo.gmon file generated, run
          gprof -l /path/to/unstripped/foo foo.gmon
          to get a flat profile]

--
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