Python [Django] + Uwsgi设置揭秘

Question

There are quite a few settings in uwsgi (emperor mode) that I don't quite understand what the actual usage are and advantages, let alone setting the correct values.

they are:

• signal-bufsize
• buffer-size
• sharedarea

I have tried reading the documentation eg. http://uwsgi-docs.readthedocs.org/en/latest/SharedArea.html but I still struggle to truly understand.

Please can someone explain those 3 settings, and how I can work out the correct values for them?

Some more background, I host quite a few different django projects, but all of them are isolated which means they don't really need to know each other, do those settings actually have any use in my scenario?

Answer 1

I've worked with a very large scale uWSGI emperor installation with thousands of vassals. We had to adjust buffer-size but not sharedarea or signal-bufsize.

• sharedarea is for inter worker communication. ie: inter process communication. But it is very low level. Literally sharing memory pages.
• buffer-size is the amount of memory uWSGI allocates to store the request headers in while it is processing the request. If you are storing large amounts of data as cookies then the default can be too small.
• signal-bufsize This one I'm not really sure about. It's never been clear to me what signals we are talking about here and I've never had to change it. But from reading this mailing list thread ( http://lists.unbit.it/pipermail/uwsgi/2013-November/006629.html ) it looks like it is the buffer used when communicating with mule processes.