Intel® VTune™ Profiler User Guide

User Guide

Contents

Best Practices: Resolve
Intel® VTune™
Profiler
 BSODs, Crashes, and Hangs in Windows* OS

Scenario

When you use
Intel® VTune™
Profiler
 to profile target applications on Windows systems, if you experience problems with an unresponsive UI or tool crashes, the following suggestions can help you get better clarity on the root causes. Verify if one of these scenarios apply to your environment. If you need further assistance, contact us to get help.

BSOD from Incompatible
Intel® VTune™
Profiler
 Driver or Windows Update

What is happening?
Intel® VTune™
Profiler
 runs well on a Windows system. After an update to the OS,
Intel® VTune™
Profiler
 crashes for certain analysis types, while others are unavailable.
Why is it happening?
Sometimes, the latest version of
Intel® VTune™
Profiler
 may be one update behind the latest version of Windows OS. The changes contained in the Windows update can then cause an incompatibility with VTune Profiler drivers, particularly with the stack sampling driver for hardware-event based sampling (HEBS) collections. Ideally, you should upgrade to the latest version of
Intel® VTune™
Profiler
 after every time you update Windows OS. This ensures that all relevant drivers are installed.
When you install
Intel® VTune™
Profiler
 on an unsupported version of Windows, the installer does not install incompatible drivers. This disables HEBS and stack collection. However, you may still be able to run hotspots or threading analyses that use user-mode sampling. If you proceed to upgrade Windows to a newer, unsupported version, the user-mode sampling collections attempt to use unavailable drivers and cause
Intel® VTune™
Profiler
 to crash.
Every time you upgrade to the latest version of Windows OS, uninstall your existing version of
Intel® VTune™
Profiler
 and install the latest available version.

BSOD from Driver Conflict

What is happening?
A BSOD occurs due to a driver conflict that affects
Intel® VTune™
Profiler
 drivers.
Why is it happening?
Sometimes, there can be a conflict between
Intel® VTune™
Profiler
 drivers and graphics or third-party drivers. This can likely happen if the
Intel® VTune™
Profiler
 drivers are out of date.
Update all
Intel® VTune™
Profiler
 drivers by installing the latest available version.

VTune Profiler UI turns Unresponsive or 'Hangs'

What is happening?
During symbol resolution stage,
Intel® VTune™
Profiler
 stalls or hangs without any response.
Why is it happening?
Several reasons can cause
Intel® VTune™
Profiler
 to hang during the collection and finalization phase.
PDB File Retrieval
When symbol resolution happens in the finalization process,
Intel® VTune™
Profiler
 may have to retrieve and process large
.pdb
 files. If used within Microsoft Visual Studio,
Intel® VTune™
Profiler
 uses the Visual Studio settings to find symbol files and any additional paths provided in
Intel® VTune™
Profiler
 settings. However, if
Intel® VTune™
Profiler
 uses a symbol server, the resolution waits on updates and therefore slows down. Depending on the size of the
.pdb
 files, this may cause
Intel® VTune™
Profiler
 to stall or hang.
If your analysis requires symbols for system libraries, use a local cache (like the location defined in Visual Studio) instead of a symbol server. Also, remove large
.pdb
 files from the symbol location you provide to
Intel® VTune™
Profiler
 if these files are not required for your analysis.
Synchronization with other Processes
Certain processes like virus scanners or synchronization/back-up utilities can interfere with data collection and finalization in
Intel® VTune™
Profiler
. Virus scanners can cause problems in the process that
Intel® VTune™
Profiler
 uses for software-based analysis types, such as threading. Some synchronization utilities can cause finalization to fail if the backup happens as
Intel® VTune™
Profiler
 is processing it.
Exclude the
pin.exe
 process from your virus scanning software or disable the scan when running a
Intel® VTune™
Profiler
 collection. Also, pause synchronization and/or back-up utilities until
Intel® VTune™
Profiler
 finalization is complete.

Intel® VTune™
Profiler
 Crashes during a Collection

What is happening?
Intel® VTune™
Profiler
 crashes in the middle of a collection operation.
Why is it happening?
A crash can happen if
Intel® VTune™
Profiler
 attempts to instrument or attach to a privileged process or service.
Run
Intel® VTune™
Profiler
 as an administrator. You can then profile processes with elevated privileges. You can also configure
Intel® VTune™
Profiler
 to profile specific modules. See the
Advanced
 section in the WHAT pane for this purpose.

Other Techniques to Enable Data Collection

What is happening?
Intel® VTune™
Profiler
 does not perform data collection in some specific situations.
Why is it happening?
Certain specific actions can cause data collection to fail. See if one of these suggestions helps to resolve your issue.
Problem
Suggestion
User-mode sampling for Threading analysis is too slow or creates too much overhead.
Run Threading analysis with Hardware-Event Based Sampling (HEBS) and context switches enabled. This provides the context switch data necessary to understand thread behavior.
Hotspots analysis is unavailable with HEBS and stack collection enabled.
Disable stack collection. To correlate hotspots with stacks, run a separate hotspots analysis with user-mode sampling enabled.
Intel® VTune™
Profiler
 hangs or crashes when attaching to a running process.
Run
Intel® VTune™
Profiler
 with the application in paused state. Resume data collection when the application gets to an area of interest.
Data collection crashes when using the Instrumentation and Tracing Technology (ITT) API.
Create a custom analysis. Disable the checkbox to analyze user tasks, events, and counters. Identify if the API is causing the crash.

Get Help

The suggestions described in this topic can help resolve several crashes or stalls. If you are still facing issues, contact us so we may better assist you.

Product and Performance Information

1

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