nginx ssl slow

[Maxim Dounin]

Hello!

On Tue, Jul 12, 2011 at 01:10:38PM +0400, Maxim Dounin wrote:

> Hello!
> 
> On Tue, Jul 12, 2011 at 01:39:33AM -0400, davidkazuhiro wrote:
> 
> > Wait I'm confused... how do you know these tests were done with EDCHE
> > ciphers?
> 
> This is just a guess based on ciphers OpenSSL 1.0.0d prefers by 
> default when working with nginx and stunell.
> 
> > And if they were, how did he do them if nginx doesn't support
> > EDCHE?
> 
> Forcing cipher to be what equally supported by all programs 
> tested.  Good testing programs even have switches to specify that. 
> :)
> 
> E.g. numbers are from virtual machine on my poor old P4 laptop, 
> stunnel passing connections to nginx, using cipher as selected by 
> my browser during real work:
> 
> $ http_load -cipher CAMELLIA256-SHA -parallel 10 -seconds 10 stunnel
> 540 fetches, 10 max parallel, 23220 bytes, in 10.008 seconds
> 43 mean bytes/connection
> 53.9568 fetches/sec, 2320.14 bytes/sec
> msecs/connect: 2.12899 mean, 24.401 max, 0.196 min
> msecs/first-response: 105.195 mean, 414.064 max, 23.386 min
> HTTP response codes:
>   code 200 -- 540
> 
> And here is nginx proxy_pass'ing to itself, same cipher:
> 
> $ http_load -cipher CAMELLIA256-SHA -parallel 10 -seconds 10 nginx
> 766 fetches, 10 max parallel, 32938 bytes, in 10.0081 seconds
> 43 mean bytes/connection
> 76.538 fetches/sec, 3291.13 bytes/sec
> msecs/connect: 1.62532 mean, 22.692 max, 0.262 min
> msecs/first-response: 79.0284 mean, 239.204 max, 21.643 min
> HTTP response codes:
>   code 200 -- 766
> 
> And as a reference point, direct requests to non-ssl nginx (used 
> as backend in both tests above):
> 
> $ http_load -parallel 10 -seconds 10 nossl
> 7536 fetches, 10 max parallel, 324048 bytes, in 10.0008 seconds
> 43 mean bytes/connection
> 753.542 fetches/sec, 32402.3 bytes/sec
> msecs/connect: 0.70163 mean, 30.059 max, 0.02 min
> msecs/first-response: 6.044 mean, 48.126 max, 0.281 min
> HTTP response codes:
>   code 200 -- 7536
> 
> So you may see nginx is a bit faster than stunnel when 
> CAMELLIA256-SHA cipher used.  On the other hand, using default 
> ciphers would produce something like this:
> 
> $ http_load -parallel 10 -seconds 10 stunnel
> 243 fetches, 10 max parallel, 10449 bytes, in 10.0243 seconds
> 43 mean bytes/connection
> 24.2411 fetches/sec, 1042.37 bytes/sec
> msecs/connect: 2.03381 mean, 18.384 max, 0.188 min
> msecs/first-response: 239.767 mean, 628.098 max, 68.431 min
> HTTP response codes:
>   code 200 -- 243
> 
> (actually used cipher: ECDHE-RSA-AES256-SHA)
> 
> $ http_load -parallel 10 -seconds 10 nginx
> 144 fetches, 10 max parallel, 6192 bytes, in 10.0126 seconds
> 43 mean bytes/connection
> 14.3818 fetches/sec, 618.418 bytes/sec
> msecs/connect: 1.44656 mean, 12.673 max, 0.427 min
> msecs/first-response: 395.734 mean, 836.928 max, 124.105 min
> HTTP response codes:
>   code 200 -- 144
> 
> (actually used cipher: DHE-RSA-AES256-SHA)
> 
> Here you can see that ECDHE cipher is about 2x times faster 
> compared to DHE.  I believe this is what actually was observed by 
> author of test you've referenced.  Both are 3x times slower than 
> CAMELLIA256-SHA as shown above though.
> 
> And again, disclaimer: all of the above tests ssl handshaking 
> speeds, not real https workload.  Real workloads are expected 
> to be much different.

Just for completenes, results with the ECDH patch[1] using the 
same ECDHE-RSA-AES256-SHA cipher as in stunnel case above:

$ http_load -parallel 10 -seconds 10 nginx
279 fetches, 10 max parallel, 11997 bytes, in 10.018 seconds
43 mean bytes/connection
27.8498 fetches/sec, 1197.54 bytes/sec
msecs/connect: 1.63012 mean, 37.961 max, 0.272 min
msecs/first-response: 206.536 mean, 604.134 max, 62.889 min
HTTP response codes:
  code 200 -- 279

(the above disclaimer still applies)

[1] http://nginx.org/pipermail/nginx-devel/2011-January/000645.html

Maxim Dounin