35-40% performance drop releng9 vs releng10 openvpn

[John-Mark Gurney]

Mike Tancsa wrote this message on Sun, Mar 15, 2015 at 20:34 -0400:
> As part of moving from a RELENG8 based image to a RELENG9 or 10, I was 
> doing some simple performance testing and found RELENG_9 to be quite a 
> bit faster when generating traffic through a pcengines APU (dual core, 
> AMD64, 2G of RAM).  Both are using generic kernels
> 
> blasting across an aes-128cbc tunnel, on releng9 I get
> 
> 
> # dd if=/dev/zero | nc 10.3.24.25 500
> 
> 326002688 bytes transferred in 37.188139 secs (8766308 bytes/sec)
> 
> 
> vs
> 
> # dd if=/dev/zero | nc 10.3.24.25 500
> 146982400 bytes transferred in 27.750440 secs (5296579 bytes/sec)
> on releng10.
> 
> Both have identical pf rules, but disabling pf does not make much of a 
> difference in speed.
> 
> I havent started checking any of the default tunables. The box will be 
> functioning as a VPN router and I was hoping to get at least 50Mb/s out 
> of it, and I can do that on RELENG9, but not 10.
> Any ideas what to do with RELENG10 to get comparable performance out of it ?

Since you have at test framework ready, you could generate some flame
graphs[1] using dtrace to help see where things might be having an
impact...

These are very easy to generate, and posting them would be useful...

[1] http://www.brendangregg.com/FlameGraphs/cpuflamegraphs.html

-- 
  John-Mark Gurney				Voice: +1 415 225 5579

     "All that I will do, has been done, All that I have, has not."