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System Calls Instrument

Overview

Instrument Description

The System Calls Instrument captures information about system calls and their duration. It can record information from a single process or from all processes running on the system.

Supported Platforms

iOS

OS X

Related Profiling Templates

System Trace Profiling Template

Timeline Pane

The timeline pane displays the number of system calls that start and end during the time period.

Record Settings

This instrument doesn’t have any record settings you can configure.

Display Settings

Click the Display Settings button (image: ../Art/instruments_displaysettings_button_inline_2x.png) in the inspector pane to customize the following display settings.

Call Tree

The following call tree display settings filter the call tree in the detail pane.

Setting

State

Separate by Thread

Off by default.

Invert Call Tree

On by default.

Hide System Symbols

Off by default.

Flatten Recursion

Off by default.

Call Tree Constraints

The following options filter the call tree to display calls that fall within a specific threshold based on the settings below.

Setting

State

# Calls

Off by default.

Data Mining

Allows you to filter through the collected data for specific symbols and libraries.

Signposts

Allows you to add definitions for signposts you’ve added to your source code, so you can track them in the detail pane event list.

Detail Pane Columns

Summary Detail Type

The following summary columns are available in the detail pane.

Column name

Definition

Graph

Determines if the process is graphed in the timeline pane.

Process

The name of the process.

Count

The number of events associated with the process.

Duration

The total duration of the process.

CPU Time

The total CPU time used by the process.

Wait Time

The total wait time spent by the process.

Time Division Ratios

The amount of time spent in the various states.

Call Tree Detail Type

The following call tree columns are available in the detail pane.

Column name

Definition

# Self

The number of times the symbol has been called.

Calls

The number of calls involving the symbol.

% of Parent

The percentage of bytes used by the call’s parent.

Source Path

The path to the source file that generated the call.

Category

An icon representing the category of the call.

Library

The name of the library that generated the call.

Symbol Name

The name of the symbol being called.

Event List Detail Type

The following event list columns are available in the detail pane.

Column name

Definition

#

The sequence number of the event.

Timestamp

The time that the event occurred.

Name

The name of the event.

Process

The process the event occurred on.

Core

The CPU core the event occurred on.

Thread

The thread name the event occurred on.

CPU Time

The amount of CPU time taken by the event.

Wait Time

The amount of time the thread had to wait before executing.

Arg0

Hexadecimal representation of the passed argument.

Arg1

Hexadecimal representation of the passed argument.

Arg2

Hexadecimal representation of the passed argument.

Arg3

Hexadecimal representation of the passed argument.

Return

Hexadecimal representation of the returned value.