On Apr 16, 2009, at 3:20 AM, Phillip B Oldham wrote:

> Barry Abrahamson wrote:
>>
>> Yes, except the vast majority images are generated dynamically, so
>> they don't exist on a filesystem anywhere :)
> Wouldn't it be faster to have the image generation script push the
> file to a memcached store on creation, and have nginx check this
> store before falling back to the generation script?

Maybe, but speed isn't the main issue here, the requests are served
generally "fast enough" Its scaling a single box to serve a huge
number of requests/sec.

BTW, I enabled http keep alives in nginx, and it seems to have reduced
softirq by about 5% which is pretty good. I guess setting up and
tearing down all of those TCP connections has a little bit of
overhead. We have sacrificed a little bit of RAM to deal with the
huge number of established connections (50k ish), but thats ok. I'm
wondering if there are even more optimizations like this which could
reduce sofirq even more.


--
Barry Abrahamson | Systems Wrangler | Automattic
Blog: http://barry.wordpress.com