Note
The System Overview analysis is supported only with the Intel® VTune™ Amplifier for Systems.
System Overview is a platform-wide analysis that monitors general behavior of your target Linux* or Android* system and correlates power and performance metrics with the interrupt request (IRQ) handling. This analysis type uses the Perf*-based driverless sampling collection that is based on NMI and enables analyzing IRQ handlers code even if IRQs are masked.
For Linux targets, the System Overview analysis collects the following Ftrace* events: sched, freq, idle, workq, irq, softirq.
For Android targets, the System Overview analysis collects the following events:
Atrace* events: input, view, webview, audio, video, camera, hal, res, dalvik
Ftrace events: sched, freq, idle, workq, filesystem, irq, softirq, sync, disk
To use the System Overview analysis, explore:
Configuration options (knobs)
Viewpoints
Configuration Options
To configure options for the System Overview analysis:
Click the
New Analysis button on the
Intel® VTune™ Amplifier
toolbar.
The New Amplifier Result tab opens with the Analysis Type window active.
From the analysis tree on the left pane, select Platform Analysis > System Overview.
The analysis configuration pane opens on the right.
Configure the following options:
CPU sampling interval, ms field
Specify an interval (in milliseconds) between CPU samples.
Possible values - 0.01-1000.
The default value is 0.10000000000000001.
Collection Level options
Select a level of details provided with event-based sampling collection. Detailed collection levels cause higher overhead.
- Hotspots
- Hotspots and stacks
The default value is Hotspots.
Details button
Expand/collapse a section listing the default non-editable settings used for this analysis type. If you want to modify these settings for the analysis, you need to create a custom configuration by right-clicking the analysis entry in the analysis tree and selecting Copy from Current from the context menu. VTune Amplifier creates an editable copy of this analysis type configuration and locates it under the Custom Analysis branch in the analysis tree.
Note
You may generate the command line for this configuration using the Command Line... button at the bottom.
Viewpoints
VTune Amplifier collects the data, generates a rxxxso result, and opens it in the default Hardware Events viewpoint that displays statistics of monitored hardware events: estimated count and/or the number of samples collected.
For System Overview analysis, start with the Top Interrupt Handlers and Interrupt Duration Histogram sections of the Summary window. Identify slow interrupt handlers and switch to the grid view grouped by Interrupt/Interrupt Duration Type/Function/Call Stack for further interrupts analysis.
You can also choose to view System Overview analysis results in the following viewpoints:
Viewpoint |
Description |
|---|---|
Hardware Issues |
Helps identify where the application is not making the best use of available hardware resources. This viewpoint displays metrics derived from hardware performance counters. Hover over the highlighted metrics values in the grid to read why the extreme value might represent a performance problem. |
Hotspots |
Helps identify hotspots - code regions in the application that consume a lot of CPU time. |
Platform Power Analysis |
Helps identify where the application is generating idle and wake-up behavior that can lead to inefficient use of energy. Where possible, it provides data from both the OS and hardware perspective, such as the detailed C-state residency report that shows the OS requested time in deep sleep states compared to the actual residency the hardware indicated. This viewpoint is available for VTune Amplifier for Systems only. |
These viewpoints may include the following windows:
Summary window displays statistics on the overall application execution.
Event Count window displays the event count for all processor events selected for the analysis. This view provides an estimated number of times an event occurred during the collection.
Sample Count window displays the sample count for all collected processor events. This view provides the actual number of samples collected for an event.
Uncore Event Count window displays counts of uncore events selected for the analysis. If there are no uncore events, the upper pane of the window is empty.
Caller/Callee window displays parent and child functions of the selected focus function. This window is available only if stack collection was enabled during analysis configuration.
Top-down Tree window displays hotspot functions in the call tree, performance metrics for a function only (Self value) and for a function and its children together (Total value).
Platform window provides details on CPU and GPU utilization, frame rate, memory bandwidth, and user tasks (if corresponding metrics are collected).
Graphics window displays overtime data as GPU usage on a software queue, CPU time usage, OpenCL™ kernels data, and GPU performance per the Overview group of GPU hardware metrics, Memory Bandwidth, and CPU Frequency.