src/beam_stats_state.erl

   1 -module(beam_stats_state).
   2
   3 -include("include/beam_stats.hrl").
   4
   5 -export_type(
   6     [ t/0
   7     ]).
   8
   9 -export(
  10     [ new/0
  11     , update/1
  12     , export/1
  13     ]).
  14
  15 -record(?MODULE,
  16     { timestamp             :: erlang:timestamp()
  17     , node_id               :: atom()
  18     , memory                :: [{atom(), non_neg_integer()}]
  19
  20     , previous_io_bytes_in  :: non_neg_integer()
  21     , previous_io_bytes_out :: non_neg_integer()
  22     , current_io_bytes_in   :: non_neg_integer()
  23     , current_io_bytes_out  :: non_neg_integer()
  24
  25     , previous_context_switches :: non_neg_integer()
  26     ,  current_context_switches :: non_neg_integer()
  27
  28     , reductions                :: non_neg_integer()
  29     , run_queue                 :: non_neg_integer()
  30     }).
  31
  32 -define(T, #?MODULE).
  33
  34 -opaque t() ::
  35     ?T{}.
  36
  37 -spec new() ->
  38     t().
  39 new() ->
  40     { {input  , CurrentIOBytesIn}
  41     , {output , CurrentIOBytesOut}
  42     } = erlang:statistics(io),
  43     {CurrentContextSwitches, 0} = erlang:statistics(context_switches),
  44     {_ReductionsTotal, ReductionsDelta} = erlang:statistics(reductions),
  45     RunQueue = erlang:statistics(run_queue),
  46     ?T
  47     { timestamp             = os:timestamp()
  48     , node_id               = erlang:node()
  49     , memory                = erlang:memory()
  50     , previous_io_bytes_in  = 0
  51     , previous_io_bytes_out = 0
  52     , current_io_bytes_in   = CurrentIOBytesIn
  53     , current_io_bytes_out  = CurrentIOBytesOut
  54     , previous_context_switches = 0
  55     ,  current_context_switches = CurrentContextSwitches
  56     , reductions                = ReductionsDelta
  57     , run_queue                 = RunQueue
  58     }.
  59
  60 -spec update(t()) ->
  61     t().
  62 update(?T
  63     { previous_io_bytes_in  = PreviousIOBytesIn
  64     , previous_io_bytes_out = PreviousIOBytesOut
  65     , previous_context_switches = PreviousContextSwitches
  66     }
  67 ) ->
  68     { {input  , CurrentIOBytesIn}
  69     , {output , CurrentIOBytesOut}
  70     } = erlang:statistics(io),
  71     {CurrentContextSwitches, 0} = erlang:statistics(context_switches),
  72     {_ReductionsTotal, ReductionsDelta} = erlang:statistics(reductions),
  73     RunQueue = erlang:statistics(run_queue),
  74     ?T
  75     { timestamp             = os:timestamp()
  76     , node_id               = erlang:node()
  77     , memory                = erlang:memory()
  78     , previous_io_bytes_in  = PreviousIOBytesIn
  79     , previous_io_bytes_out = PreviousIOBytesOut
  80     , current_io_bytes_in   = CurrentIOBytesIn
  81     , current_io_bytes_out  = CurrentIOBytesOut
  82     , previous_context_switches = PreviousContextSwitches
  83     ,  current_context_switches = CurrentContextSwitches
  84     , reductions                = ReductionsDelta
  85     , run_queue                 = RunQueue
  86     }.
  87
  88 -spec export(t()) ->
  89     beam_stats:t().
  90 export(
  91     ?T
  92     { timestamp             = Timestamp
  93     , node_id               = NodeID
  94     , memory                = Memory
  95     , previous_io_bytes_in  = PreviousIOBytesIn
  96     , previous_io_bytes_out = PreviousIOBytesOut
  97     , current_io_bytes_in   = CurrentIOBytesIn
  98     , current_io_bytes_out  = CurrentIOBytesOut
  99     , previous_context_switches = PreviousContextSwitches
 100     ,  current_context_switches = CurrentContextSwitches
 101     , reductions                = Reductions
 102     , run_queue                 = RunQueue
 103     }
 104 ) ->
 105     #beam_stats
 106     { timestamp    = Timestamp
 107     , node_id      = NodeID
 108     , memory       = Memory
 109     , io_bytes_in  = CurrentIOBytesIn  - PreviousIOBytesIn
 110     , io_bytes_out = CurrentIOBytesOut - PreviousIOBytesOut
 111     , context_switches = CurrentContextSwitches - PreviousContextSwitches
 112     , reductions       = Reductions
 113     , run_queue        = RunQueue
 114     }.