Key Terms

baseline: A performance metric used as a basis for comparison of the application versions before and after optimization. Baseline should be measurable and reproducible.

CPU time: The amount of time a thread spends executing on a logical processor. For multiple threads, the CPU time of the threads is summed. The application CPU time is the sum of the CPU time of all the threads that run the application.

CPU usage: A performance metric when the VTune Amplifier identifies a processor utilization scale, calculates the target CPU usage, and defines default utilization ranges depending on the number of processor cores.

Utilization Type

Default color

Description

Idle

All CPUs are waiting - no threads are running.

Poor

Poor usage. By default, poor usage is when the number of simultaneously running CPUs is less than or equal to 50% of the target CPU usage.

OK

Acceptable (OK) usage. By default, OK usage is when the number of simultaneously running CPUs is between 51-85% of the target CPU usage.

Ideal

Ideal usage. By default, Ideal usage is when the number of simultaneously running CPUs is between 86-100% of the target CPU usage.

Elapsed time:The total time your target ran, calculated as follows: Wall clock time at end of application – Wall clock time at start of application.

finalization: A process during which the Intel® VTune™ Amplifier converts the collected data to a database, resolves symbol information, and pre-computes data to make further analysis more efficient and responsive.

hotspot: A section of code that took a long time to execute. Some hotspots may indicate bottlenecks and can be removed, while other hotspots inevitably take a long time to execute due to their nature.

Basic Hotspots analysis: An analysis type used to understand the application flow and identify hotspots. VTune Amplifier creates a list of functions in your application ordered by the amount of time spent in a function. It also detects the call stacks for each of these functions so you can see how the hot functions are called. VTune Amplifier uses a low overhead (about 5%) user-mode sampling and tracing collection that gets you the information you need without slowing down the application execution significantly.

target: A target is an executable file you analyze using the Intel® VTune™ Amplifier.

viewpoint: A preset result tab configuration that filters out the data collected during a performance analysis and enables you to focus on specific performance problems. When you select a viewpoint, you select a set of performance metrics the VTune Amplifier shows in the windows/panes of the result tab. To select the required viewpoint, click the (change) link and use the drop-down menu at the top of the result tab.

Reportez-vous à notre Notice d'optimisation pour plus d'informations sur les choix et l'optimisation des performances dans les produits logiciels Intel.