[Click] Click running on multi-core processor

[Bingyang LIU]

Hi all,

I'm using click for performance evaluation of IPSec. But it seems that only
one core of the processor is used. I'm wondering how Click can fully use
the multi-core for computation to achieve high performance.

The detail of my experiment is as follows:

* Hardware: CPU Inter Xeon X3210 (quad core at 2.13Ghz), 4GB RAM. (a server
on deterlab)
* Software: Ubuntu8.04 + Click1.8, with PollDevice enabled.
* Configuration: ./configure --with-linux=/usr/src/linux-2.6.24.7
--enable-ipsec --enable-warp9 --enable-multithread=4 (I also tried 16, but
the outcome is similar with 4)
* mode: kernel

The outcome:
* The click router has the loss rate of about 0.5% when incoming packet
rate is only 200000 pps (packet size = 64B). If I remove the ipsec modules,
the loss rate is about 0.1%.
* I checked the CPU usage. Anyway, the click used only one cpu.
* If there is no input packet, the cpu usage is as follows, I guess
PollDevice consumes the cpu time:
Cpu0  :  0.0%us,  0.0%sy,  0.0%ni,100.0%id,  0.0%wa,  0.0%hi,  0.0%si,
 0.0%st
Cpu1  :  0.0%us,  0.0%sy,  0.0%ni,100.0%id,  0.0%wa,  0.0%hi,  0.0%si,
 0.0%st
Cpu2  :  0.0%us, 48.0%sy,  0.0%ni, 25.0%id,  0.0%wa,  0.0%hi, 27.0%si,
 0.0%st
Cpu3  :  0.0%us,  0.0%sy,  0.0%ni,100.0%id,  0.0%wa,  0.0%hi,  0.0%si,
 0.0%st
* If there is some input packets, the cpu usage is as follows. It seems
that the IPSec module only consumes a small portion of the CPU time, which
causes low performance.
Cpu0  :  0.0%us,  0.0%sy,  0.0%ni,100.0%id,  0.0%wa,  0.0%hi,  0.0%si,
 0.0%st
Cpu1  :  0.0%us,  0.0%sy,  0.0%ni,100.0%id,  0.0%wa,  0.0%hi,  0.0%si,
 0.0%st
Cpu2  :  0.0%us, 68.8%sy,  0.0%ni, 25.0%id,  0.0%wa,  0.0%hi,  6.2%si,
 0.0%st
Cpu3  :  0.0%us,  0.0%sy,  0.0%ni,100.0%id,  0.0%wa,  0.0%hi,  0.0%si,
 0.0%st

So what I'm wondering is that, is there any solution to my problem?
Or is there any easy way to fully use the CPU resource, or achieve
parallelism in a multi-core router? Is the paper "Flexible Control of
Parallelism in a Multiprocessor PC Router" the only available solution?

thanks!
best
Bingyang
-- 
Bingyang Liu
Network Architecture Lab, Network Center,Tsinghua Univ.
Beijing, China
Home Page: http://netarchlab.tsinghua.edu.cn/~liuby