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et_collector(3erl) | Erlang Module Definition | et_collector(3erl) |
NAME¶
et_collector - Collect trace events and provide a backing storage appropriate for iterationDESCRIPTION¶
Interface module for the Event Trace (ET) applicationEXPORTS¶
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, boolean()} |
{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 filter with a customized dito it is possible
to allow any trace data as input. The collector filter is a dictionary entry
with the predefined 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
matching 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:
stop(CollectorPid) -> ok
- *
- parent_pid - self().
- *
- event_order - trace_ts.
- *
- trace_global - false.
- *
- trace_pattern - undefined.
- *
- trace_port - 4711.
- *
- trace_max_queue - 50.
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)
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
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 supervises 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 backwards 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.
et 1.5 | Ericsson AB |