Minimize Analysis Overhead
Minimize
Analysis OverheadRunning your target application with the
can take substantially longer than running your target application without the
.
Intel® Advisor
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
analysis data.
Intel® Advisor
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 | Pause collection:
Resume collection:
C# and .NET support is deprecated starting
Intel® Advisor 2021.1.
|
Start target application with collection paused
|
| Start target application with collection paused:
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:
checkbox
advisor CLI action option:
-resume-after=<integer> |
Stop collection after N seconds
| All
| GUI control:
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
![]() advisor CLI action option:
-mark-up-list=<string> |
Select loops by source file/line
|
| GUI control:
Survey Report
![]() advisor CLI action:
-mark-up-loops with action option
-select=<string> |
Select loops by criteria
|
| GUI control:
Workflow pane
> Batch mode settings
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:
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:
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:
checkbox
advisor CLI action option:
-no-stack-stitching |
Increase sampling interval
| Survey
| GUI control:
field
advisor CLI action option:
interval=<integer>
|
Limit collected analysis data
| Survey
| GUI control:
field
advisor CLI action option:
-data-limit=<integer> |
Limit loop call count
|
| GUI control:
field
advisor CLI action option:
-loop-call-count-limit=<integer> |
Disable additional analysis
| Survey
| GUI controls:
...
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 |