Pane: Analysis Type - Advanced Hotspots

To access this pane:

  1. Click the New Analysis button on the Intel® VTune™ Amplifier toolbar.

    The New Amplifier Result tab opens with the Analysis Type window active.

  2. From the analysis tree on the left pane, select Algorithm Analysis > Advanced Hotspots.

    The analysis configuration pane opens on the right.

Use this pane to explore and edit the predefined Advanced Hotspots analysis type configuration that uses the hardware event-based sampling mechanism for data collection. This configuration helps you find out where your application is not using the hardware resources effectively. For this analysis, the VTune Amplifier uses a set of hardware events that enable monitoring the application performance against hardware metrics defined by Intel architects.

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CPU sampling interval, ms spin box

Specify an interval between collected CPU samples in milliseconds.

Collection level options

Select a level of details provided with event-based sampling collection:

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Hotspots

Identify application hotspots based on such basic hardware events as Clockticks and Instructions Retired.

Hotspots, stacks and context switches

Identify hardware hotspots, explore statistically reconstructed call flow of your program and analyze thread scheduling.

Hotspots, call counts, stacks and context switches

Identify hardware hotspots, analyze thread scheduling, explore call stacks and statistically approximated number of calls to sampled functions.

Event mode drop-down list

Limit event-based sampling collection to USER (user events) or OS(system events) mode. By default, all event types are collected.

Analyze user tasks check box

Analyze tasks specified in your code via Task API.

Analyze Processor Graphics hardware events drop-down menu

Analyze performance data from Intel HD Graphics based on the predefined groups of GPU metrics.

Trace OpenCL kernels on Processor Graphics check box

Capture the execution time of OpenCL kernels on a GPU, identify performance-critical GPU computing tasks, and analyze the performance of OpenCL kernels per GPU hardware metrics.

Analyze DirectX pipeline events check box

Analyze GPU usage and frame rate based on the data provided by the DirectX* and identify whether your application is GPU or CPU bound.

Note

You are recommended to enable stack collection to detect context switches and correlate CPU and GPU usage data.

Details button

Expand/collapse a section listing the default non-editable settings used for this analysis type. If you want to modify these settings, click the Copy button in the upper right corner. VTune Amplifier creates an editable copy of this analysis type configuration and locates it under the Custom Analysis node in the analysis tree.

The Details section provides information on the following default collection settings used for the Advanced Hotspots analysis:

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Events table

Explore events used by the selected analysis for your system.

Events Data

Description

Event Name

Name of the event to monitor.

Sample After

Number of events after which the VTune Amplifier interrupts the event data collection. The Sample After value depends on the target duration. Based on the duration value, the VTune Amplifier adjusts the Sample After value with a multiplier.

LBR Filter

Last branch records (LBRs) filter applied to the event collection.

Event Description

Brief information on the event. For more details, see the Reference for Processor Events.

Note

You may copy the command line for this configuration using the Command Line... button at the bottom and run this analysis remotely.

For more complete information about compiler optimizations, see our Optimization Notice.