Intel® VTune™ Profiler User Guide

User Guide

Contents

Manage Analysis Duration from Command Line

Manage analysis duration for best results on short-running targets, or to minimize collection overhead on longer-running targets.
Use the
vtune
 command interface to minimize duration while optimizing the analysis process.

Use Default Duration

Intel® VTune™
Profiler
 provides predefined general analysis types to keep overhead to a reasonable level. The option reference topic for the collect action identifies analysis types that are recommended as starting points; and points out some more advanced analysis types that have higher overhead.
To view all the analysis types that are available for your processor, use the command line help:
vtune
 -help collect

Adjust Collection Duration to Application

The sampling interval determines how much data is collected. The default sampling interval is
short
, which is appropriate for targets that complete in 1 - 15 minutes.
If your target runs shorter or longer than this, use the
target-duration-type
 action-option to set the appropriate duration type, which adjusts the sampling interval.
  • If the target takes less than 1 minute to run, specify
    veryshort
    .
  • If the target takes 15 minutes to 3 hours to run, specify
    medium
    .
  • If the target takes over 3 hours, specify
    long
    .
For hardware event-based analysis types, a multiplier applies to the configured Sample After value.
Example
Perform a Hotspots analysis in the
user-mode sampling
 mode using a medium sampling interval that is appropriate for targets with a duration of 15 minutes to 3 hours. 
vtune -collect hotspots -target-duration-type medium -- myApp

Manually Interrupt and Restart Analysis

To pause an analysis manually, open a new terminal and use the command action with the
pause
 argument, being sure to specify the result directory. The target process continues to run, but data collection is paused. 
vtune -command pause -result-dir results/r002hs
To resume analysis, use the
command
 action with the
resume
 argument. 
vtune -command resume -r results/r002hs
To stop analysis altogether, use the
command
 action with the
stop
 argument. Once analysis is stopped, it cannot be resumed. 
vtune -command stop -r results/r002hs

Configure Collection Duration

VTune
Profiler
 offers other ways to limit the analysis process. To stop analysis at a specified time after initiating target execution, use the duration option.
vtune
 -collect <
analysis_type
> -duration=<
value
> -- <
target
>
where
  • <
    analysis_type
    >
     is the type of analysis to run
  • <
    value
    >
     is the duration in seconds
  • <
    target
    >
     is the target to analyze
To start the analysis in the paused mode or pause the collection during the analysis, refer to Pause Collection from the Command Line section.
Examples
Example 1: Ending analysis after specified time
Start a Hotspots analysis of
myApplication
 and end analysis after 60 seconds. 
vtune -collect hotspots -duration=60 -- /home/test/myApplication
Example 2: Running an unlimited duration analysis
Run an unlimited duration Hotspots analysis, which will run until you stop it. 
vtune -collect hotspots -duration=unlimited -result-dir results/r002hs

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.