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Starting a Recording From the JRockit Command Line

Use the -XXjra command in combination with an option listed in Table 3-1, for example, -XXjra:recordingtime to specify the duration of the recording.

Table 3-1 Command Line Startup Options
Option
Description
delay
Amount of time, in seconds, to wait before recording starts.
recordingtime
Duration, in seconds, for the recording. This is an optional parameter. If you don't use it, the default is 60 seconds.
filename
The name of recording file. This is an optional parameter. If you don't use it, the default is jrarecording.xml.
sampletime
The time, in milliseconds, between samples. Do not use this parameter unless you are familiar with how it works. This is an optional parameter.
nativesamples
Displays method samples in native code; that is, you will see the names of functions written in C-code. This is an optional parameter.
methodtraces
You can set this to false to disable the stack trace collection that otherwise happens for each sample. The default value is true.
tracedepth
Sets the number of frames that will be captured when collecting stack traces. Possible value are 0 through 16. The default value is 16.
heapstat=<true | false>
Allows you to enable or disable the tracking of heap statistics.
  • -XXjra:heapstat=true enables heap statistic tracking
  • -XXjra:heapstat=false disables heap statistic tracking.
This tracking is enabled by default but, under certain circumstances can adversely affect transaction latency. In those situations, it is strongly recommended that you disable heap statistic tracking.

Note: Setting methodtraces to false can still result in some stack traces being captured. These stack traces are captured as part of JRockit's dynamic optimizations and will have a depth of 3. If optimizations are turned off (-Xnoopt) these traces will not be captured.

The startup options that you have used are shown in the VM Arguments tab on the General tab. See View VM Arguments.

Listing 3-1 shows an example of how you can setup a JRA recording.

Listing 3-1 An example of using the -XXjra startup command:
-XXjra:delay=10,recordingtime=100,filename=jrarecording2.xml
would result in a recording that: 
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