Thanks to help from the uwsgi group (Specifically Ryan Showalter and Lukasz Mierzwa) I learned about two important settings to help speed up web2py sites.
I hope this advice helps anyone else who is using uwsgi and has a very slow site with traffic starts poring in. 1) Set --cpu-affinity when you are starting uwsgi. I used 3 so 3 processes will be handled by each processor (I set 12 workers in nginx config, 3 Workers * 4 CUPs) http://lists.unbit.it/pipermail/uwsgi/2011-March/001594.html 2) Use a socket file instead of the TCP stack with uwsgi_pass and when starting uwsgi: in uwsgi config use: "socket = /var/run/uwsgi.socket" in nginx config use: "uwsgi_pass unix:///var/run/uwsgi.socket;" http://lists.unbit.it/pipermail/uwsgi/2011-September/002625.html Comments directly from Lukasz: It's hard to saturate single core with just one worker since it might wait for external resources like memcached, db or client, 2-4 workers per core seems like a good starting point, but check how many workers can fit in ram before you start setting very high max number of workers. Once you're out of memory and you hit swap all the performance of fast server is gone. If you use cgroup memory limits in uWSGI than it will start swapping workers memory to disk once they eat all memory they can. If you use max-requests or memory limits in uWSGI config than check how long does it take in peak hours to hit that limit and reload worker, it might happen to frequently, and if your app takes to long to start it might slow everything down. Keep in mind that high number of workers may hit max database connection limit (it depends on db you use). As always - if you can benchmark you workers, apache benchmark or siege are good enough to get some idea of how many request per second you can get. Also - if you can change the way nginx talks to uwsgi - instead of local tcp connection use file socket - you want hammer tcp stack with a lot of connections. in uwsgi config use: "socket = /var/run/uwsgi.socket" in nginx config use: "uwsgi_pass unix:///var/run/uwsgi.socket;" -- -- Regards, Bruce Wade http://ca.linkedin.com/in/brucelwade http://www.wadecybertech.com http://www.fittraineronline.com - Fitness Personal Trainers Online http://www.warplydesigned.com
