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Core Data Faults Instrument

Overview

Instrument Description

The Core Data Faults instrument captures information on fault events that occur during the lazy initialization of an NSManagedObject or its to-many relationship in a Core Data application. It can record information from a single process or all processes running on the system. The all-processes option records information only from running Core Data applications. You can export recorded information to a DTrace script.

Supported Platforms

OS X

Related Profiling Templates

N/A

Timeline Pane

The timeline pane displays the following information, based on the instrument’s configuration:

Display name

Definition

Fault duration

The numeric file descriptor.

Thread ID (tid)

The thread identifier.

Stack Depth

The depth of the stack when the operation was performed.

Relationship fault duration

The duration of the relationship fault.

Record Settings

Click the Record Settings button (image: ../Art/instruments_recordsettings_button_inline_2x.png) in the inspector pane to customize the following recording options.

Select statistics to list

Select the statistics to be displayed in the Statistics to Graph area.

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.

Track Display Settings

These settings control how information is displayed in the timeline pane.

Setting

Description

Options

Style

How information is presented.

  • Block Graph: Information is presented as a horizontal line until the information changes. The area under the line is filled by the statistic’s designated color.

  • Peak Graph: Maximum value for the information is displayed. Lines are in the statistic’s designated color.

Statistics to Graph

Select a statistic to see it graphed in the timeline pane. Click the shape or the color well to change how a statistic is represented.

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

Off by default.

Hide System Libraries

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.

Detail Pane Columns

Event List Detail Type

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

Column name

Definition

#

The sequence number of the event.

Caller

Caller of the performed action.

Fault object

The name of the object causing the fault.

Fault duration

The execution duration of the fault handler in microseconds.

Relationship fault source

The source of the relationship fault.

Relationship

The name of the relationship.

Relationship fault duration

The duration of the relationship fault.

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 percentage of total calls involving the symbol name.

# Calls

The number of calls involving the symbol name.

% 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.