firefox in 8.1-RELEASE: High CPU consumption?

[Antonio Vieiro]

Hi all,

I'm observing what I think a high CPU usage with the "www/firefox" port 
in 8.1-RELEASE.

Even with a blank page loaded (about:blank) I see CPU loads around 7-9%.

I've done a truss on the browser and I see what appears to be a loop and 
some "timeout" and "resource temporarily unavailable" results on calls 
to "read". I'm attaching a gzipped file with the result of truss.

I'd appreciate if you could shed some light on this.

Thanks,
Antonio

P.S.:

* uname -a
FreeBSD antonio.antonioshome.net 8.1-RELEASE FreeBSD 8.1-RELEASE #0: Mon 
Jul 19 02:55:53 UTC 2010 
root at almeida.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC  i386

* Makefile timestamp
11662064 -rw-r--r--  1 root  wheel  3799 21 jul 15:31 Makefile

* Where the problem occurs:
When running firefox (3.6.4).

* How to reproduce the problem:
Launch firefox and go to "about:blank". Run truss against the process.
I can always reproduce this problem.