Visible to Intel only — GUID: GUID-F8C4F59C-83BE-4CCA-8EF9-2C8945BE9908
Visible to Intel only — GUID: GUID-F8C4F59C-83BE-4CCA-8EF9-2C8945BE9908
Minimize Analysis Overhead
Running your target application with the Intel® Advisor can take substantially longer than running your target application without the Intel® Advisor. Depending on an accuracy level and analyses you choose for a perspective, different overhead is added to your application execution time. For example:
Runtime Overhead / Analysis |
Survey |
Characterization |
Dependencies |
MAP |
---|---|---|---|---|
Target application runtime with Intel® Advisor compared to runtime without Intel® Advisor |
1.1x longer |
2 - 55x longer |
5 - 100x longer |
5 - 20x longer |
The following tables summarize how to minimize overhead while collecting and finalizing Intel® Advisor analysis data.
Collection Controls
The following table is a summary. For more information, see Collection Controls to Minimize Analysis Overhead.
Minimization Technique |
Impacted Analyses |
Summary |
---|---|---|
Pause collection/Resume collection using API methods |
|
Pause collection:
Resume collection:
|
Pause collection/Resume collection using annotations |
Some analysis types recognize the structural annotations typically used in the Threading perspective workflow. |
Pause collection:
Resume collection:
NOTE:
C# and .NET support is deprecated starting Intel® Advisor 2021.1.
|
Start target application with collection paused |
|
Start target application with collection paused:
NOTE:
You can use different techniques to resume collection. The most common is __itt_resume |
Start target application with collection paused/Resume collection after N seconds |
|
GUI control: Project Properties > Analysis Target > [Name] Analysis > Advanced > Automatically resume collection after (sec) checkbox advisor CLI action option: -resume-after=<integer> |
Stop collection after N seconds |
All |
GUI control: Project Properties > Analysis Target > [Name] Analysis > Advanced > Automatically stop collection after (sec) checkbox and field advisor CLI action: -stop-after=<integer> |
Stop collection |
All |
GUI control: Workflow pane > Stop current analysis control and Site Coverage widget advisor CLI: action option: -command=stop |
Manually pause collection/Manually resume collection |
|
Pause collection:
Resume collection:
|
Attach to process/Detach from process |
|
Attach to process:
Detach from process:
|
Loop Markup
The following table is a summary. For more information, see Loop Markup to Minimize Analysis Overhead.
Minimization Technique |
Impacted Intel Advisor Analyses |
Summary |
---|---|---|
Select loops by ID |
|
GUI control: Survey Report checkbox(es) advisor CLI action option: -mark-up-list=<string> |
Select loops by source file/line |
|
GUI control: Survey Report checkbox(es) advisor CLI action: -mark-up-loops with action option -select=<string> |
Select loops by criteria |
|
advisor CLI: action -mark-up-loops or -collect with action option -loops=<string> |
Filtering
The following table is a summary. For more information, see Filtering to Minimize Analysis Overhead.
Minimization Technique |
Impacted Intel Advisor Analyses |
Summary |
---|---|---|
Filter modules |
|
GUI control: Project Properties > Analysis Target > [Name] Analysis > Modules options and field advisor CLI: action option: -module-filter-mode=include | exclude and -module-filter=<string> |
Execution Speed/Duration/Scope Properties
The following table is a summary. For more information, see Execution Speed/Duration/Scope Properties to Minimize Analysis Overhead.
Minimization Technique |
Impacted Intel Advisor Analyses |
Summary |
---|---|---|
Change stackwalk mode from offline (after collection) to online (during collection) |
Survey |
GUI control: Project Properties > Analysis Target > Survey Hotspots Analysis > Advanced > Stack unwinding mode > During collection advisor CLI action option: -stackwalk-mode=online |
Disable stacks collection |
|
GUI controls:
advisor CLI action option: -no-stacks (or just ensure the CLI action option -stacks is omitted from the advisor command line) |
Disable stitch stacks |
Survey |
GUI control: Project Properties > Analysis Target > Survey Hotspots Analysis > Advanced > Stitch stacks checkbox advisorCLI action option: -no-stack-stitching |
Increase sampling interval |
Survey |
GUI control: Project Properties > Analysis Target > Survey Hotspots Analysis > Advanced > Sampling interval field advisor CLI action option: interval=<integer> |
Limit collected analysis data |
Survey |
GUI control: Project Properties > Analysis Target > Survey Hotspots Analysis > Advanced > Collection data limit, MB field advisor CLI action option: -data-limit=<integer> |
Limit loop call count |
|
GUI control: Project Properties > Analysis Target > [Name] Analysis > Advanced > Loop Call Count Limit field advisor CLI action option: -loop-call-count-limit=<integer> |
Disable additional analysis |
Survey |
GUI controls: Project Properties > Analysis Target > Survey Hotspots Analysis > Advanced...
advisor CLI action options:
|
Miscellaneous Techniques
The following table is a summary. For more information, see Miscellaneous Techniques to Minimize Analysis Overhead.
Minimization Technique |
Impacted Intel Advisor Analyses |
Summary |
---|---|---|
Disable cache simulation |
|
GUI controls:
advisor CLI action option: -no-enable-cache-simulation |
Limit reported data |
Memory Access Patterns |
GUI controls:
advisor CLI action options:
|
Minimize data set |
All, but especially:
|
Minimize number of instructions executed within a loop while thoroughly exercising target application control flow paths |
Temporarily disable finalization until opening result in GUI |
|
GUI control: Workflow pane > Cancel current analysis control during finalization advisor CLI action option: -no-auto-finalize |