The following subcommands can be used with the collector command within dbx to control the types of data that are collected by the Collector. They are ignored with a warning if an experiment is active.
Controls the collection of clock profiling data. The allowed values for option are:
on – Enables clock profiling with the default profiling interval of 10 ms.
off – Disables clock profiling.
timer interval - Sets the profiling interval . The allowed values of interval are:
on – Use the default profiling interval of approximately 10 milliseconds.
lo[w] – Use the low-resolution profiling interval of approximately 100 milliseconds.
hi[gh] – Use the high-resolution profiling interval of approximately 1 millisecond. See Limitations on Clock Profiling for information on enabling high-resolution profiling.
value - Set the profiling interval to value. The default units for value are milliseconds. You can specify value as an integer or a floating-point number. The numeric value can optionally be followed by the suffix m to select millisecond units or u to select microsecond units. The value should be a multiple of the clock resolution. If the value is larger than the clock resolution but not a multiple, it is rounded down. If the value is smaller than the clock resolution it is set to the clock resolution. In both cases, a warning message is printed.
The default setting is approximately 10 milliseconds.
The Collector collects clock profiling data by default, unless the collection of hardware-counter profiling data is turned on using the hwprofile subcommand.
Controls the collection of hardware counter profiling data. If you attempt to enable hardware counter profiling on systems that do not support it, dbx returns a warning message and the command is ignored. The allowed values for option are:
on – Turns on hardware counter profiling. The default action is to collect data for the cycles counter at the normal overflow value.
off – Turns off hardware counter profiling.
list – Returns a list of available counters. See Hardware Counter Lists for a description of the list. If your system does not support hardware counter profiling, dbx returns a warning message.
counter counter-definition... [, counter-definition ] – A counter definition takes the following form.
[+]counter-name[~ attribute_1=value_1]...[~attribute_n =value_n][/ register-number][,rate ]
Selects the hardware counter name and sets its overflow value to rate; optionally selects additional hardware counter names and sets their overflow values to the specified rate. The sampling frequency rate has the following valid values:
auto– Match the rate used by clock-profiling. If clock-profiling is disabled, use the per-thread maximum rate of approximately 100 samples per second. auto is the default and preferred setting.
lo[w] – Use the per-thread maximum rate of approximately 10 samples per second.
hi[gh] – Use the per-thread maximum rate of approximately 10 samples per second.
value – Specify a fixed event interval value to trigger a sample, rather than a sampling rate. When specifying value, note that the actual frequency is dependent on the selected counter and the program under the test.
If you specify more than one counter, each counter must use different registers. If they do not, a warning message is printed and the command is ignored.
If the hardware counter counts events that relate to memory access, you can prefix the counter name with a + sign to turn on searching for the true PC of the instruction that caused the counter overflow. If the search is successful, the PC and the effective address that was referenced are stored in the event data packet.
The Collector does not collect hardware counter profiling data by default. If hardware-counter profiling is enabled and a profile command has not been issued, clock profiling is turned off.
Controls the collection of synchronization wait tracing data. The allowed values for option are:
on – Enable synchronization wait tracing with the default threshold.
off – Disable synchronization wait tracing.
threshold value - Sets the threshold for the minimum synchronization delay. The allowed values for value are:
all – Use a zero threshold. This option forces all synchronization events to be recorded.
calibrate – Set the threshold value by calibration at runtime. (Equivalent to on.)
off – Turn off synchronization wait tracing.
on – Use the default threshold, which is to set the value by calibration at runtime. (Equivalent to calibrate.)
number - Set the threshold to number, given as a positive integer in microseconds. If value is 0, all events are traced.
By default, the Collector does not collect synchronization wait tracing data.
Controls the collection of heap tracing data. The allowed values for option are:
on – Enable heap tracing.
off – Disable heap tracing.
By default, the Collector does not collect heap tracing data.
Collect data for data race detection or deadlock detection for the Thread Analyzer. The allowed values are:
off – Turn off thread analyzer data collection.
all – Collect all thread analyzer data.
race – Collect data-race-detection data.
deadlock – Collect deadlock and potential-deadlock data.
For more information about the Thread Analyzer, see the Oracle Developer Studio 12.6: Thread Analyzer User’s Guide and the tha.1 man page.
Controls the sampling mode. The allowed values for option are:
periodic – Enable periodic sampling.
manual – Disable periodic sampling. Manual sampling remains enabled.
period value – Set the sampling interval to value, given in seconds.
By default, periodic sampling is enabled, with a sampling interval value of 1 second.
Controls the recording of samples when dbx stops the target process. The meanings of the keywords are as follows:
on – A sample is recorded each time dbx stops the target process.
off – Samples are not recorded when dbx stops the target process.
By default, samples are recorded when dbx stops the target process.