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     }).
  30
  31 -define(T, #?MODULE).
  32
  33 -opaque t() ::
  34     ?T{}.
  35
  36 -spec new() ->
  37     t().
  38 new() ->
  39     { {input  , CurrentIOBytesIn}
  40     , {output , CurrentIOBytesOut}
  41     } = erlang:statistics(io),
  42     {CurrentContextSwitches, 0} = erlang:statistics(context_switches),
  43     {_ReductionsTotal, ReductionsDelta} = erlang:statistics(reductions),
  44     ?T
  45     { timestamp             = os:timestamp()
  46     , node_id               = erlang:node()
  47     , memory                = erlang:memory()
  48     , previous_io_bytes_in  = 0
  49     , previous_io_bytes_out = 0
  50     , current_io_bytes_in   = CurrentIOBytesIn
  51     , current_io_bytes_out  = CurrentIOBytesOut
  52     , previous_context_switches = 0
  53     ,  current_context_switches = CurrentContextSwitches
  54     , reductions                = ReductionsDelta
  55     }.
  56
  57 -spec update(t()) ->
  58     t().
  59 update(?T
  60     { previous_io_bytes_in  = PreviousIOBytesIn
  61     , previous_io_bytes_out = PreviousIOBytesOut
  62     , previous_context_switches = PreviousContextSwitches
  63     }
  64 ) ->
  65     { {input  , CurrentIOBytesIn}
  66     , {output , CurrentIOBytesOut}
  67     } = erlang:statistics(io),
  68     {CurrentContextSwitches, 0} = erlang:statistics(context_switches),
  69     {_ReductionsTotal, ReductionsDelta} = erlang:statistics(reductions),
  70     ?T
  71     { timestamp             = os:timestamp()
  72     , node_id               = erlang:node()
  73     , memory                = erlang:memory()
  74     , previous_io_bytes_in  = PreviousIOBytesIn
  75     , previous_io_bytes_out = PreviousIOBytesOut
  76     , current_io_bytes_in   = CurrentIOBytesIn
  77     , current_io_bytes_out  = CurrentIOBytesOut
  78     , previous_context_switches = PreviousContextSwitches
  79     ,  current_context_switches = CurrentContextSwitches
  80     , reductions                = ReductionsDelta
  81     }.
  82
  83 -spec export(t()) ->
  84     beam_stats:t().
  85 export(
  86     ?T
  87     { timestamp             = Timestamp
  88     , node_id               = NodeID
  89     , memory                = Memory
  90     , previous_io_bytes_in  = PreviousIOBytesIn
  91     , previous_io_bytes_out = PreviousIOBytesOut
  92     , current_io_bytes_in   = CurrentIOBytesIn
  93     , current_io_bytes_out  = CurrentIOBytesOut
  94     , previous_context_switches = PreviousContextSwitches
  95     ,  current_context_switches = CurrentContextSwitches
  96     , reductions                = Reductions
  97     }
  98 ) ->
  99     #beam_stats
 100     { timestamp    = Timestamp
 101     , node_id      = NodeID
 102     , memory       = Memory
 103     , io_bytes_in  = CurrentIOBytesIn  - PreviousIOBytesIn
 104     , io_bytes_out = CurrentIOBytesOut - PreviousIOBytesOut
 105     , context_switches = CurrentContextSwitches - PreviousContextSwitches
 106     , reductions       = Reductions
 107     }.