prolog_profile.pl -- Execution profiler

This module provides a simple frontend on the execution profiler with a hook to the GUI visualiser for profiling results defined in library(swi/pce_profile).

profile(:Goal)

profile(:Goal, +Options)

Run once(Goal) under the execution profiler. If the (xpce) GUI is enabled this predicate is hooked by library(swi/pce_profile) and results are presented in a gui that enables navigating the call tree and jump to predicate implementations. Without the GUI, a simple textual report is generated. Defined options are:

time(Which): Profile cpu or wall time. The default is CPU time.
sample_rate(Rate): Samples per second, any numeric value between 1 and 1000
ports(Bool): Specifies ports counted - true (all ports), false (call port only) or classic (all with some errors). Accomodates space/accuracy tradeoff building call tree.
top(N): When generating a textual report, show the top N predicates.
cumulative(Bool): If true (default false), show cumulative output in a textual report.

See also: - show_coverage/2 from library(test_cover).
To be done: - The textual input reflects only part of the information.

show_profile(+Options)

Display last collected profiling data. Options are

top(N): When generating a textual report, show the top N predicates.
cumulative(Bool): If true (default false), show cumulative output in a textual report.

profile_data(-Data) is det

Gather all relevant data from profiler. This predicate may be called while profiling is active in which case it is suspended while collecting the data. Data is a dict providing the following fields:

summary:Dict

Overall statistics providing

samples:Count: Times the statistical profiler was called
ticks:Count Virtual ticks during profiling
accounting:Count Tick spent on accounting
time:Seconds Total time sampled
nodes:Count Nodes in the call graph.
sample_period: MicroSeconds Same interval timer period in micro seconds
ports: Ports One of true, false or classic

nodes

List of nodes. Each node provides:

predicate:PredicateIndicator
ticks_self:Count
ticks_siblings:Count
call:Count
redo:Count
exit:Count
callers:list_of(Relative)
callees:list_of(Relative)

Relative is a term of the shape below that represents a caller or callee. Future versions are likely to use a dict instead.

node(PredicateIndicator, CycleID, Ticks, TicksSiblings,
     Calls, Redos, Exits)

prof_statistics(-Node) is det[private]

Get overall statistics

Arguments:

Node - term of the format prof(Ticks, Account, Time, Nodes)

profile_procedure_data(?Pred, -Data:dict) is nondet

Collect data for Pred. If Pred is unbound data for each predicate that has profile data available is returned. Data is described in profile_data/1 as an element of the nodes key.

value(+Key, +NodeData, -Value)[private]

Obtain possible computed attributes from NodeData.

Re-exported predicates

The following predicates are exported from this file while their implementation is defined in imported modules or non-module files loaded by this module.

profile(:Goal)

profile(:Goal, +Options)

time(Which): Profile cpu or wall time. The default is CPU time.
sample_rate(Rate): Samples per second, any numeric value between 1 and 1000
ports(Bool): Specifies ports counted - true (all ports), false (call port only) or classic (all with some errors). Accomodates space/accuracy tradeoff building call tree.
top(N): When generating a textual report, show the top N predicates.
cumulative(Bool): If true (default false), show cumulative output in a textual report.

See also: - show_coverage/2 from library(test_cover).
To be done: - The textual input reflects only part of the information.