LuaJIT NYI codes

[WenMing]

@sumory there are some codes in Lor can not be compiled by LuaJIT.

attachment 1.txt is generated by jit.dump. You can use like this:

init_by_lua '
        local v = require "jit.v"
        v.on("/tmp/jit.log")
    ';

[WenMing]

this tool https://github.com/agentzh/nginx-devel-utils/blob/master/ljbc.lua can explain bytecode 51. for example:

$ /usr/local/openresty/luajit/bin/luajit-2.1.0-alpha ljbc.lua 51
    opcode 51:
    FNEW

that's means new a function.

other bytecode numbers are also this method

[午夜]

i'll try to make some improvement about these performance issues in the next main version of lor. :)

[WenMing]

I will try to generate flame graph to find more performance issues.
by the way, if we have thousands of locations, can the router of lor handle them quickly like NGINX?

[午夜]

Unfortunately, lor is not as fast as Nginx when handling thousands of locations.

• the locations(uri) are organized as a pipeline with a stack/array structure.
• every request will pass through this pipeline to find middlewares that are adapted to it.
• this feature is powerful for business logic like some other frameworks do(such as express) , however it's also a tradeoff with lower performance.
• as a result for test, the Hello World test case for Nginx/OpenResty is 2x faster than lor. however it's still hard to design a meaningful and reasonable test case cause lor will process several steps while Nginx only performs ngx.say("hello world").
• no more specific test cases were performed.

Currently, we can improve the performance with these measures:

• local app = lor(), init routes and middlewares with lor in a separate lua module, and then invoke app:run() in the main endpoint.
• if we exactly know when to exit this request, we should invoke the response methods(res:json/res:text/res:render...) as soon as possible.

[午夜]

another possible and effective way to optimize is to separate app initialization to init_by_lua block. but it's such a big change for the architecture of this framework and use experience for developers. maybe i will have a try on it with more tests.

[Yufu Zhao]

@moonbingbing I had did this test before.

1. lor performance optimization trick

I don't think it's a problem that the lor should as fast as the original ngx_lua. It's like wheels run fast then the car, but it is useless if without any seats. Isn't it?