et_collector(3erl) Erlang Module Definition et_collector(3erl)
NAME
et_collector - Collect trace events and provide a backing storage ap-
propriate 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_fil-
ter_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(), ex-
tended_dbg_match_spec()} | undefined
report_module() = atom() | undefined
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, New-
Event}
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 op-
tion 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 re-
ported events are first filtered thru the collector filter be-
fore 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 val-
ues 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:
* 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, Rea-
son}
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 success-
fully written to file (clear).
The options defaults to existing, write and keep.
report(Handle, TraceOrEvent) -> {ok, Continuation} | exit(Reason)
report_event(Handle, DetailLevel, FromTo, Label, Contents) -> {ok, Con-
tinuation} | 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 option-
ally 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_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 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
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 1.6.4 et_collector(3erl)