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Diffstat (limited to 'Examples/php_cputime_example.txt')
| -rw-r--r-- | Examples/php_cputime_example.txt | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/Examples/php_cputime_example.txt b/Examples/php_cputime_example.txt new file mode 100644 index 000000000000..db218e1d1f53 --- /dev/null +++ b/Examples/php_cputime_example.txt @@ -0,0 +1,58 @@ +The following are examples of php_cputime.d. + +This script traces the on-CPU time of PHP functions and prints a report. +Here it traces the example program, Code/Php/func_abc.php. + +# php_cputime.d +Tracing... Hit Ctrl-C to end. +^C + +Count, + FILE TYPE NAME COUNT + func_abc.php func func_a 1 + func_abc.php func func_b 1 + func_abc.php func func_c 1 + func_abc.php func sleep 3 + - total - 6 + +Exclusive function on-CPU times (us), + FILE TYPE NAME TOTAL + func_abc.php func func_c 17 + func_abc.php func func_b 25 + func_abc.php func func_a 74 + func_abc.php func sleep 93 + - total - 210 + +Inclusive function on-CPU times (us), + FILE TYPE NAME TOTAL + func_abc.php func func_c 39 + func_abc.php func func_b 87 + func_abc.php func sleep 93 + func_abc.php func func_a 210 + +In total, six functions were called; sleep was called three times and there +was one call each of func_a(), func_b() and func_c(). + +The exclusive subroutine on-CPU times show that func_a() spent around 74 +microseconds on-CPU, func_b() spent 25 microseconds on-CPU, and func_c() spent +17 microseconds on-CPU. This exclusive times excludes time spent in other +subroutines. + +The inclusive subroutine on-CPU times show that func_c() spent around 39 +microseconds on-CPU, func_b() spent around 87 microseconds on-CPU and +func_a() spent around 210 microseconds. This inclusive time includes the time +spent in other functions called (including sleep), and since func_a() called +func_b() which called func_c(), these times make perfect sense. + +These on-CPU times are the time the program spent running on a CPU, from when +the function began to when it completed. This does not include time +spent off-CPU time such as sleeping for I/O or waiting for scheduling. + +On-CPU times are useful for showing who is causing the CPUs to be busy. +See Notes/ALLoncpu_notes.txt for more details. Also see +Notes/ALLexclusive_notes.txt and Notes/ALLinclusive_notes.txt for a +detailed explanation of exclusive vs inclusive subroutine time. + +If you study the func_abc.php program alongside the above output, the numbers +should make sense. + |