ANALYZEALLOCATION(1) — UNIX Programmer’s Manual

NAME

AnalyzeAllocation − analyze memory allocation statistics.

SYNOPSIS

AnalyzeAllocation [-help] [-v] file

DESCRIPTION

AnalyzeAllocation analyzes the allocation statistics gathered by the Foundation Framework (see NSDebug.h). To gather all allocation statistics, you can set NSKeepAllocationStatistics to YES in your environment and then run the application. This records allocation statistics in a file named /tmp/alloc_stats_application_pid. This file gets very large very quickly, in addition to making your program run much more slowly, so it’s important not to run too much of your program with the NSKeepAllocationStatistics environment variable turned on. Instead, run a specific task, then turn the environment variable off.

As an alternative, you can control what portions of the running application are measured by setting the global variable NSKeepAllocationStatistics to YES when you want to gather statistics and NO when you do not. This variable is defined in the Foundation Framework file NSDebug.h.

After you have gathered statistics, you run the AnalyzeAllocation command to analyze them. AnalyzeAllocation with no options prints a table that summarizes the allocation statistics. For each class, the table provides the following information:

retain Invocations of the default retain implementation

release
Invocations of the default release implementation

iretain
Invocations of an override of retain

irelease
Invocations of an override of release

autorelease
Invocations of autorelease

copy Invocations of copy

instances
Number of instances still alive

max Maximum number of instances at one time

total Total number of instances created

class Name of the class

The -v option prints a detailed analysis for each class, consisting of:

    The number of objects allocated
    The number of objects deallocated
    Shortest lifetime (in seconds) of any object of this class
    Median lifetime (in seconds) of any object of this class
    Maximum lifetime (in seconds) of any object of this class
    Number of ephemeral objects, objects that lasted less than 0.01 seconds
    Minimum number of retains on any object of this class
    Median number of retains on all objects of this class
    Maximum number of retains on any object of this class
    Minimum number of releases on any object of this class
    Median number of releases on all objects of this class
    Maximum number of releases on any object of this class
    Minimum number of invocations of an override of retain for any object of this class
    Median number of invocations of an override of retain on all objects
    Maximum number of invocations of an override of retain on any object
    Minimum number of invocations of an override of release on any object
    Median number of invocations of an override of release on all objects
    Maximum number of invocations of an override of release on any object
    Minimum number of autoreleases on any object
    Median number of autoreleases on all objects
    Maximum number of autoreleases on any object
    Minimum number of copies on any object
    Median number of copies on all objects
    Maximum number of copies on any object
    Minimum number of retains on any instance of this class
    Median number of retains on all objects
    Maximum number of retains on any object

OPTIONS

-help Displays a message describing how to use AnalyzeAllocation.

-v Displays a different set of statistics as described above.

file The file to be analyzed. Its name has the form /tmp/alloc_stats_appName_pid

EXAMPLES

# setenv NSKeepAllocationStatistics YES
# /NextDeveloper/Demos/TextEdit.app/TextEdit
run for a while, then quit
# unsetenv NSKeepAllocationStatistics
# AnalyzeAllocation -v /tmp/alloc_stats_Edit_∗