contrib/statusd/statusd_meminfo.lua

   1 -- Authors: Tibor Csögör <tibi@tiborius.net>
   2 -- License: Public domain
   3 -- Last Changed: 2006-11-14
   4 --
   5 -- $Id: statusd_meminfo.lua 59 2006-11-14 11:17:02Z tibi $
   6
   7 -- statusd_meminfo.lua -- memory and swap usage monitor for Ion3's statusbar
   8
   9 -- version : 0.1
  10 -- date    : 2006-11-14
  11 -- author  : Tibor Csögör <tibi@tiborius.net>
  12
  13 -- Shows the memory and swap usage of the system.
  14 -- This script depends on the /proc filesystem and thus only works on Linux.
  15 -- Tested with kernel 2.6.16.
  16
  17 -- Configuration:
  18 -- The placeholders `mem_total', `mem_used', `mem_free', `mem_buffers',
  19 -- `mem_cached', `swap_total', `swap_used' and `swap_free' hold the same
  20 -- information as the corresponding fieds in top(1).  `mem_used_adj' and
  21 -- `mem_free_adj' are adjusted values, here buffers and cached memory count as
  22 -- free.  Placeholders suffixed with `_p' yield percentage values.
  23
  24 -- Example usage:
  25 -- "MEM: %meminfo_mem_free_adj free, SWAP: %meminfo_swap_used used".
  26
  27 -- This software is in the public domain.
  28
  29 --------------------------------------------------------------------------------
  30
  31
  32 local defaults = {
  33    update_interval = 1000, -- 1 second
  34 }
  35
  36 local settings = table.join(statusd.get_config("meminfo"), defaults)
  37
  38 local meminfo_timer = statusd.create_timer()
  39
  40 function math.round(num, idp)
  41    local mult = 10^(idp or 0)
  42    return math.floor(num  * mult + 0.5) / mult
  43 end
  44
  45 local function guess_mem_unit(amount)
  46    amount = tonumber(amount)
  47    if (amount < 1024) then
  48       return amount .. "k"
  49    elseif (amount >= 1024) and (amount < 1048576) then
  50       return math.round((amount / 1024)) .. "M"
  51    elseif (amount > 1048576) then
  52       return math.round((amount / 1048576), 1) .. "G"
  53    end
  54 end
  55
  56 local function get_meminfo()
  57    local meminfo_table = {}
  58    local f = io.open('/proc/meminfo', 'r')
  59    if (f == nil) then return nil end
  60    local s = f:read("*a")
  61    f:close()
  62    local i = 0
  63    while (i < string.len(s)) do
  64       local j, k, v
  65       i, j, k, v = string.find(s, "([%w_]+):%s+(%d+) kB\n", i)
  66       if (i == nil) then return nil end
  67       meminfo_table[k] = tonumber(v)
  68       i = j+1
  69    end
  70    return meminfo_table
  71 end
  72
  73 local function update_meminfo()
  74    local t = get_meminfo()
  75    if (t == nil) then return nil end
  76
  77    statusd.inform("meminfo_mem_total", guess_mem_unit(t.MemTotal))
  78    statusd.inform("meminfo_mem_used", guess_mem_unit(t.MemTotal - t.MemFree))
  79    statusd.inform("meminfo_mem_used_p",
  80                   math.round(((t.MemTotal-t.MemFree)/t.MemTotal)*100) .. "%")
  81    statusd.inform("meminfo_mem_used_adj",
  82                   guess_mem_unit(t.MemTotal-(t.MemFree+t.Buffers+t.Cached)))
  83    statusd.inform("meminfo_mem_used_adj_p", math.round(
  84                   ((t.MemTotal-(t.MemFree+t.Buffers+t.Cached))/t.MemTotal)*100)
  85                   .. "%")
  86    statusd.inform("meminfo_mem_free", guess_mem_unit(t.MemFree))
  87    statusd.inform("meminfo_mem_free_p", math.round((t.MemFree/t.MemTotal)*100)
  88                   .. "%")
  89    statusd.inform("meminfo_mem_free_adj",
  90                   guess_mem_unit(t.MemFree+t.Buffers+t.Cached))
  91    statusd.inform("meminfo_mem_free_adj_p",
  92                   math.round(((t.MemFree+t.Buffers+t.Cached)/t.MemTotal)*100)
  93                   .. "%")
  94    statusd.inform("meminfo_mem_buffers", guess_mem_unit(t.Buffers))
  95    statusd.inform("meminfo_mem_cached", guess_mem_unit(t.Cached))
  96    statusd.inform("meminfo_swap_total", guess_mem_unit(t.SwapTotal))
  97    statusd.inform("meminfo_swap_free", guess_mem_unit(t.SwapFree))
  98    statusd.inform("meminfo_swap_free_p",
  99                   math.round((t.SwapFree/t.SwapTotal)*100) .. "%")
 100    statusd.inform("meminfo_swap_used", guess_mem_unit(t.SwapTotal-t.SwapFree))
 101    statusd.inform("meminfo_swap_used_p",
 102                   math.round(((t.SwapTotal-t.SwapFree)/t.SwapTotal)*100) .. "%")
 103
 104    meminfo_timer:set(settings.update_interval, update_meminfo)
 105 end
 106
 107 update_meminfo()
 108
 109 -- EOF