et_collector(3erl) Erlang Module Definition et_collector(3erl)
NAME
et_collector - Collect trace events and provide a backing storage appropriate for iteration
DESCRIPTION
Interface module for the Event Trace (ET) application
EXPORTS
start_link(Options) -> {ok, CollectorPid} | {error, Reason}
Types Options = [option()]
option() = {parent_pid, pid()} | {event_order, event_order()} | {dict_insert, {filter, collector}, collector_fun()} |
{dict_insert, {filter, event_filter_name()}, event_filter_fun()} | {dict_insert, {subscriber, pid()}, dict_val()} |
{dict_insert, dict_key(), dict_val()} | {dict_delete, dict_key()} | {trace_client, trace_client()} | {trace_global, bool-
ean()} | {trace_pattern, trace_pattern()} | {trace_port, integer()} | {trace_max_queue, integer()}
event_order() = trace_ts | event_ts
trace_pattern() = {report_module(), extended_dbg_match_spec()} | undefined
report_module() = atom() | undefined <v>extended_dbg_match_spec()() = detail_level() | dbg_match_spec()
detail_level() = min | max | integer(X) when X =< 0, X >= 100
trace_client() = {event_file, file_name()} | {dbg_trace_type(), dbg_trace_parameters()}
file_name() = string()
collector_fun() = trace_filter_fun() | event_filter_fun()
trace_filter_fun() = fun(TraceData) -> false | true | {true, NewEvent}
event_filter_fun() = fun(Event) -> false | true | {true, NewEvent}
event_filter_name() = atom()
TraceData = erlang_trace_data()
Event = NewEvent = record(event)
dict_key() = term()
dict_val() = term()
CollectorPid = pid()
Reason = term()
Start a collector process.
The collector collects trace events and keeps them ordered by their timestamp. The timestamp may either reflect the time when the
actual trace data was generated (trace_ts) or when the trace data was transformed into an event record (event_ts). If the time stamp
is missing in the trace data (missing timestamp option to erlang:trace/4) the trace_ts will be set to the event_ts.
Events are reported to the collector directly with the report function or indirectly via one or more trace clients. All reported
events are first filtered thru the collector filter before they are stored by the collector. By replacing the default collector fil-
ter with a customized dito it is possible to allow any trace data as input. The collector filter is a dictionary entry with the pre-
defined key {filter, collector} and the value is a fun of arity 1. See et_selector:make_event/1 for interface details, such as which
erlang:trace/1 tuples that are accepted.
The collector has a built-in dictionary service. Any term may be stored as value in the dictionary and bound to a unique key. When
new values are inserted with an existing key, the new values will overwrite the existing ones. Processes may subscribe on dictionary
updates by using {subscriber, pid()} as dictionary key. All dictionary updates will be propagated to the subscriber processes match-
ing the pattern {{subscriber, '_'}, '_'} where the first '_' is interpreted as a pid().
In global trace mode, the collector will automatically start tracing on all connected Erlang nodes. When a node connects, a port
tracer will be started on that node and a corresponding trace client on the collector node.
Default values:
* parent_pid - self().
* event_order - trace_ts.
* trace_global - false.
* trace_pattern - undefined.
* trace_port - 4711.
* trace_max_queue - 50.
stop(CollectorPid) -> ok
Types CollectorPid = pid()
Stop a collector process.
save_event_file(CollectorPid, FileName, Options) -> ok | {error, Reason}
Types CollectorPid = pid()
FileName = string()
Options = [option()]
Reason = term()
option() = event_option() | file_option() | table_option()
event_option() = existing
file_option() = write | append
table_option() = keep | clear
Save the events to a file.
By default the currently stored events (existing) are written to a brand new file (write) and the events are kept (keep) after they
have been written to the file.
Instead of keeping the events after writing them to file, it is possible to remove all stored events after they have successfully
written to file (clear).
The options defaults to existing, write and keep.
load_event_file(CollectorPid, FileName) -> {ok, BadBytes} | exit(Reason)
Types CollectorPid = pid()
FileName = string()
BadBytes = integer(X) where X >= 0
Reason = term()
Load the event table from a file.
report(Handle, TraceOrEvent) -> {ok, Continuation} | exit(Reason)
report_event(Handle, DetailLevel, FromTo, Label, Contents) -> {ok, Continuation} | exit(Reason)
report_event(Handle, DetailLevel, From, To, Label, Contents) -> {ok, Continuation} | exit(Reason)
Types Handle = Initial | Continuation
Initial = collector_pid()
collector_pid() = pid()
Continuation = record(table_handle)
TraceOrEvent = record(event) | dbg_trace_tuple() | end_of_trace
Reason = term()
DetailLevel = integer(X) when X =< 0, X >= 100
From = actor()
To = actor()
FromTo = actor()
Label = atom() | string() | term()
Contents = [{Key, Value}] | term()
actor() = term()
Report an event to the collector.
All events are filtered thru the collector filter, which optionally may transform or discard the event. The first call should use
the pid of the collector process as report handle, while subsequent calls should use the table handle.
make_key(Type, Stuff) -> Key
Types Type = record(table_handle) | trace_ts | event_ts
Stuff = record(event) | Key
Key = record(event_ts) | record(trace_ts)
Make a key out of an event record or an old key.
get_table_handle(CollectorPid) -> Handle
Types CollectorPid = pid()
Handle = record(table_handle)
Return a table handle.
get_global_pid() -> CollectorPid | exit(Reason)
Types CollectorPid = pid()
Reason = term()
Return a the identity of the globally registered collector if there is any.
change_pattern(CollectorPid, RawPattern) -> {old_pattern, TracePattern}
Types CollectorPid = pid()
RawPattern = {report_module(), extended_dbg_match_spec()}
report_module() = atom() | undefined
extended_dbg_match_spec()() = detail_level() | dbg_match_spec()
RawPattern = detail_level()
detail_level() = min | max | integer(X) when X =< 0, X >= 100
TracePattern = {report_module(), dbg_match_spec_match_spec()}
Change active trace pattern globally on all trace nodes.
dict_insert(CollectorPid, {filter, collector}, FilterFun) -> ok
dict_insert(CollectorPid, {subscriber, SubscriberPid}, Void) -> ok
dict_insert(CollectorPid, Key, Val) -> ok
Types CollectorPid = pid()
FilterFun = filter_fun()
SubscriberPid = pid()
Void = term()
Key = term()
Val = term()
Insert a dictionary entry and send a {et, {dict_insert, Key, Val}} tuple to all registered subscribers.
If the entry is a new subscriber, it will imply that the new subscriber process first will get one message for each already stored
dictionary entry, before it and all old subscribers will get this particular entry. The collector process links to and then super-
vises the subscriber process. If the subscriber process dies it will imply that it gets unregistered as with a normal dict_delete/2.
dict_lookup(CollectorPid, Key) -> [Val]
Types CollectorPid = pid()
FilterFun = filter_fun()
CollectorPid = pid()
Key = term()
Val = term()
Lookup a dictionary entry and return zero or one value.
dict_delete(CollectorPid, Key) -> ok
Types CollectorPid = pid()
SubscriberPid = pid()
Key = {subscriber, SubscriberPid} | term()
Delete a dictionary entry and send a {et, {dict_delete, Key}} tuple to all registered subscribers.
If the deleted entry is a registered subscriber, it will imply that the subscriber process gets is unregistered as subscriber as
well as it gets it final message.
dict_match(CollectorPid, Pattern) -> [Match]
Types CollectorPid = pid()
Pattern = '_' | {key_pattern(), val_pattern()}
key_pattern() = ets_match_object_pattern()
val_pattern() = ets_match_object_pattern()
Match = {key(), val()}
key() = term()
val() = term()
Match some dictionary entries
multicast(_CollectorPid, Msg) -> ok
Types CollectorPid = pid()
CollectorPid = pid()
Msg = term()
Sends a message to all registered subscribers.
start_trace_client(CollectorPid, Type, Parameters) -> file_loaded | {trace_client_pid, pid()} | exit(Reason)
Types Type = dbg_trace_client_type()
Parameters = dbg_trace_client_parameters()
Pid = dbg_trace_client_pid()
Load raw Erlang trace from a file, port or process.
iterate(Handle, Prev, Limit) -> NewAcc
Short for iterate(Handle, Prev, Limit, undefined, Prev) -> NewAcc
iterate(Handle, Prev, Limit, Fun, Acc) -> NewAcc
Types Handle = collector_pid() | table_handle()
Prev = first | last | event_key()
Limit = done() | forward() | backward()
collector_pid() = pid()
table_handle() = record(table_handle)
event_key() = record(event) | record(event_ts) | record(trace_ts)
done() = 0
forward() = infinity | integer(X) where X > 0
backward() = '-infinity' | integer(X) where X < 0
Fun = fun(Event, Acc) -> NewAcc <v>Acc = NewAcc = term()
Iterate over the currently stored events.
Iterates over the currently stored events and applies a function for each event. The iteration may be performed forwards or back-
wards and may be limited to a maximum number of events (abs(Limit)).
clear_table(Handle) -> ok
Types Handle = collector_pid() | table_handle()
collector_pid() = pid()
table_handle() = record(table_handle)
Clear the event table.
Ericsson AB et 1.4.2 et_collector(3erl)