Intel® FPGA SDK for OpenCL™ Standard Edition: Best Practices Guide

ID 683176
Date 9/24/2018
Document Table of Contents
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4.2.1. Source Code Tab

The Source Code tab in the GUI contains source code information and detailed statistics about memory and channel accesses.
Figure 63. The Source Code tab in the GUI

The Source Code tab provides detailed information on specific lines of kernel code.

Table 9.  Types of Information Available in the Source Code Tab
Column Description Access Type
Attributes Memory or channel attributes information such as memory type (local or global), corresponding memory system (DDR or quad data rate (QDR)), and read or write access. All memory and channel accesses
Stall% Percentage of time the memory or channel access is causing pipeline stalls. It is a measure of the ability of the memory or channel access to fulfill an access request. All memory and channel accesses
Occupancy% Percentage of the overall profiled time frame when a valid work-item executes the memory or channel instruction. All memory and channel accesses
Bandwidth Average memory bandwidth that the memory access uses and its overall efficiency.

For each global memory access, FPGA resources are assigned to acquire data from the global memory system. However, the amount of data a kernel program uses might be less than the acquired data. The overall efficiency is the percentage of total bytes, acquired from the global memory system, that the kernel program uses.

Global memory accesses

If a line of source code instructs more than one memory or channel operations, the profile statistics appear in a drop-down list box and you may select to view the relevant information.

Figure 64. Source Code Tab: Drop-Down List for Multiple Memory or Channel Operations