libs/core: record peak values in luci.debug
[project/luci.git] / libs / core / luasrc / debug.lua
1 local debug = require "debug"
2 local io = require "io"
3 local collectgarbage = collectgarbage
4
5 module "luci.debug"
6 __file__ = debug.getinfo(1, 'S').source:sub(2)
7
8 -- Enables the memory tracer with given flags and returns a function to disable the tracer again
9 function trap_memtrace(flags, dest)
10         flags = flags or "clr"
11         local tracefile = io.open(dest or "/tmp/memtrace", "w")
12         local peak = 0
13
14         local function trap(what, line)
15                 local info = debug.getinfo(2, "Sn")
16                 if collectgarbage("count") > peak then
17                         peak = collectgarbage("count")
18                 end
19                 if tracefile then
20                         tracefile:write(
21                                 "[", what, "] ", info.source, ":", (line or "?"), "\t",
22                                 (info.namewhat or ""), "\t",
23                                 (info.name or ""), "\t",
24                                 collectgarbage("count"), " (", peak, ")\n"
25                         )
26                 end
27         end
28
29         debug.sethook(trap, flags)
30
31         return function()
32                 debug.sethook()
33                 tracefile:close()
34         end
35 end
36