1 -module(beam_stats_process).
3 -include("include/beam_stats_process_ancestry.hrl").
4 -include("include/beam_stats_process.hrl").
15 , get_best_known_origin/1
29 #beam_stats_process_ancestry{}.
31 -type best_known_origin() ::
32 {registered_name , atom()}
33 | {ancestry , ancestry()}
41 %% ============================================================================
43 %% ============================================================================
45 -spec of_pid(pid()) ->
46 none % when process is dead
47 | {some, t()} % when process is alive
51 Dict = pid_info_exn(Pid, dictionary),
53 #beam_stats_process_ancestry
54 { raw_initial_call = pid_info_exn(Pid, initial_call)
55 , otp_initial_call = hope_kv_list:get(Dict, '$initial_call')
56 , otp_ancestors = hope_kv_list:get(Dict, '$ancestors')
61 , registered_name = pid_info_opt(Pid, registered_name)
63 , status = pid_info_exn(Pid, status)
64 , memory = pid_info_exn(Pid, memory)
65 , total_heap_size = pid_info_exn(Pid, total_heap_size)
66 , stack_size = pid_info_exn(Pid, stack_size)
67 , message_queue_len = pid_info_exn(Pid, message_queue_len)
70 catch throw:{process_dead, _} ->
79 , registered_name = RegisteredNameOpt
80 , ancestry = #beam_stats_process_ancestry
81 { raw_initial_call = InitialCallRaw
82 , otp_initial_call = InitialCallOTPOpt
83 , otp_ancestors = AncestorsOpt
87 , total_heap_size = TotalHeapSize
88 , stack_size = StackSize
89 , message_queue_len = MsgQueueLen
92 BestKnownOrigin = get_best_known_origin(T),
93 io:format("--------------------------------------------------~n"),
96 "BestKnownOrigin : ~p~n"
97 "RegisteredNameOpt : ~p~n"
98 "InitialCallRaw : ~p~n"
99 "InitialCallOTPOpt : ~p~n"
100 "AncestorsOpt : ~p~n"
103 "TotalHeapSize : ~p~n"
121 %% ============================================================================
123 %% ============================================================================
125 pid_info_exn(Pid, Key) ->
126 {some, Value} = pid_info_opt(Pid, Key),
129 pid_info_opt(Pid, Key) ->
130 case {Key, beam_stats_source:erlang_process_info(Pid, Key)}
131 of {registered_name, []} -> none
132 ; {_ , {Key, Value}} -> {some, Value}
133 ; {_ , undefined} -> throw({process_dead, Pid})
136 %% ============================================================================
137 %% Process code origin approximation or naming the anonymous processes.
139 %% At runtime, given a PID, how precicely can we identify the origin of the
140 %% code it is running?
142 %% We have these data points:
144 %% - Sometimes | registered name (if so, we're done)
145 %% - Sometimes | ancestor PIDs or registered names
146 %% - Always | initial_call (can be too generic, such as erlang:apply)
147 %% - Always | current_function (can be too far down the stack)
148 %% - Always | current_location (can be too far down the stack)
149 %% - Potentially | application tree, but maybe expensive to compute, need to check
150 %% ============================================================================
152 -define(TAG(Tag), fun (X) -> {Tag, X} end).
154 -spec get_best_known_origin(t()) ->
156 get_best_known_origin(?T{registered_name={some, RegisteredName}}) ->
157 {registered_name, RegisteredName};
158 get_best_known_origin(?T{registered_name=none, ancestry=Ancestry}) ->
159 {ancestry, Ancestry}.