Developer Guide

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Occupancy

The
occupancy
of a datapath at a point in time refers to the proportion of the datapath that contains valid data. The occupancy of a circuit over the execution of a program is the average occupancy over time from the moment the program starts to run until it has completed.
Unoccupied portions of the datapath are often referred to as
bubbles
. Bubbles are analogous to a no-operation (no-ops) instructions for a CPU that have no effect on the final output.
Decreasing bubbles increases occupancy. In the absence of other bottlenecks, maximizing occupancy of the datapath results in higher throughput.
A Datapath Through Four Iterations Showing A Bubble Traveling Through

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