Siemens XT65, TC65, AC65, XT75 manual Performance, Java, Duration of each loop = 600 s

Java User’s Guide

5.12 Performance

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5.12Performance

The performance study was focused on comparable performance values under various circum- stances.

5.12.1Java

This section gives information about the Java command execution throughput (“jPS”= Java statements per second). The scope of this measurement is only the statement execution time, not the execution delay (Java command on AT interface → Java instruction execution → reac- tion on GPIO).

Figure 13: Test case for measuring Java command execution throughput

The following Java instruction was used for calculation of the typical jPS: value = ( 2 x number of calculation statements ) /

( (1 / frequencyB ) - ( 1 / frequencyA ) );

Measurement and calculation were done using:

•duration of each loop = 600 s

•number of calculation statements = 50 “result=(CONSTANT_VALUE/variable_value);”- Instructions (executed twice per pin cycle)

•frequencyA as measured with a universal counter

•frequencyB as measured with a universal counter

The reference loop has the same structure as the measurement loop except that the measure- ment sequence is moved.

State	jPS-Value (mean)
ME in IDLE mode / Not connected	~49000
CSD connection	~46000

Since only a small amount of Java code is executed in this test, it is easily optimized by the CLDC’s HI just-in-time compiler. More complex applications might not reach that execution speed.

wm_java_usersguide_v12	Page 43 of 123	2008-02-25
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