pgbench performance is lagging compared to Linux and DragonflyBSD?

[Yuri]

There is the post by DragonflyBSD folks that claims that Linux and 
DragonflyBSD are quite ahead of FreeBSD on pgbench test on 12 Core 2x 
Xeon X5650 with 24 threads.
Here are their results with graphs: 
http://lists.dragonflybsd.org/pipermail/users/attachments/20121010/7996ff88/attachment-0002.pdf
And here is their original post: 
http://lists.dragonflybsd.org/pipermail/users/2012-October/017536.html

I am not sure if this is the problem of some sysctl or kernel parameters 
or some serious system issue.

It looks like the DragonflyBSD folks made a goal to do well on pgbench 
and got to the level of ~88% of linux with 80 clients.

Yuri