Chapter 4 - DSpace at Waseda University

The
latency
HRT analysis is based on a loop as follows:
� reads the hardirq for HRTimer
� reads softirq of HRTimer
� reads itimer_expired time
� computes formula (1) and formula (2)
5.5.1 Result of KAS
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Chapter 5
In this section, we explain the results analyzed by KAS. The result of each layer is outputted
in text type data.
5.5.1.1 Result of DL
Table 5.1 shows the results from the Detection Layer. Latency is expressed as
time tick
T - HRT , and it means HRTimer latency. We defined equation
latency
HRT ³ 100μs as
latency, and record the number of latency times where latency-count as Table 5.1. It records
not only the latency-time but also the line information (start line and end line) where the
latency has occurred.
Figure 5.9 shows a source code which saves the line information causing the latency. As
latency_start_end[start_end_num][] is two dimensional arrangement variable on which the
start_end_num saved the latency times and on the back part, information of start line and end
line of latency is saved.