Provided by: jitterdebugger_0.3.1-1_amd64 bug

NAME

       jitterdebugger - measures wake up latencies

SYNOPSIS

       jitterdebugger [OPTIONS]

DESCRIPTION

       jitterdebugger  measures  wake  up  latencies.  jitterdebugger starts a thread on each CPU
       which programs a timer and measures the time it takes from the timer  expiring  until  the
       thread which set the timer runs again.

       jitterdebugger default settings will produce a correct meassurement.

       The program runs until CTRL-C or SIGTERM is received. The results are printed to STDOUT as
       JSON encoded string.

OPTIONS

       -h, --help
              Show help text and exit.

       -v, --verbose
              Show live updates of the measurments

       -f, --file=FILE
              Write the results into the FILE

       -l, --loops=N
              Run meassurments N times and the terminate jitterdebugger.

       -b, --break=N
              Run jitterdebugger until the N or greater latency has been observed. jitterdebugger
              will  also  stop  a running tracer by writing 0 to tracing/tracing_on. Furthermore,
              the value observed will be written to the trace buffers  tracing/trace_marker,  e.g
              "Hit latency 249".

       -i, --interval=N
              Set the sleep time between each measuring. The default value is 1000us

       -o, --output=FILE
              Write  all  samples  measured  into  FILE.  This  file is binary encoded and can be
              decoded using jittersamples.

       -a, --affinity=CPUSET
              Set the CPU  affinity  mask.  jitterdebugger  starts  only  meassuring  threads  on
              CPUSET,. e.g. 0,2,5-7 starts a thread on first, third and 5, 6 and 7 CPU.  May also
              be set in hexadecimal with '0x' prefix

       -p, --priority=PRI
              Set the priority of the meassuring threads. The default value is 98. Note  priority
              99 is not available because 99 should only be used for kernel housekeeping tasks.

EXAMPLES

       # jitterdebugger  -v
       affinity: 0,1 = 2 [0x3]
       T: 0 (  614) A: 0 C:     13476 Min:         3 Avg:    3.08 Max:        10
       T: 1 (  615) A: 1 C:     13513 Min:         3 Avg:    3.10 Max:        20
       ^C
       {
         "cpu": {
           "0": {
             "histogram": {
               "3": 4070,
               "4": 269,
               "5": 26,
               "6": 5,
               "7": 1,
               "8": 1,
               "9": 2,
               "10": 1
             },
             "count": 4375,
             "min": 3,
             "max": 10,
             "avg": 3.08
           },
           "1": {
             "histogram": {
               "3": 4002,
               "4": 320,
               "5": 22,
               "6": 4,
               "7": 2,
               "8": 1,
               "10": 2,
               "11": 1,
               "16": 2,
               "20": 1
             },
             "count": 4357,
             "min": 3,
             "max": 20,
             "avg": 3.10
           }
         }
       }

SEE ALSO

       jittersamples(1) jitterplot(1)

                                                                                JITTERDEBUGGER(1)