User Guide

  • 2020
  • 06/18/2020
  • Public Content
Contents

Bottom-up Comparison

To view the difference before and after optimization for a function and its callers, click the
Bottom-up
sub-tab for the comparison result you created using the
Compare Results
window.
In the compare mode, the
Bottom-up
window shows the data columns of the two results and a new column showing the difference between the two results for each program unit. The difference is calculated as <Result 1 Value> - <Result 2 Value>.
Example: Comparison for Hotspots Analysis Results
The
Bottom-up
window displays the data columns for each result and a
Difference
column that calculates the difference between the two results. By default, the
Difference
column is collapsed and displays the total difference data per CPU time. You may click the double-arrow icon to expand the column and see comparison data per utilization level.
CPU time specific difference is calculated as <Result 1 CPU time> - <Result 2 CPU time>, which is
r000hs-r004hs
(see the tab title). Expand the first two columns to see the data used for the calculation.
For the
grid_intersect
function in this example, the difference is 3.961s - 4.470s = -0.138s of Poor CPU utilization time, which means that serial CPU time has insignificantly increased after code modification (Result 2).

Product and Performance Information

1

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.

Notice revision #20110804