| java.lang.Object | |
| ↳ | android.os.Debug |
Provides various debugging methods for Android applications, including tracing and allocation counts.
Logging Trace Files
Debug can create log files that give details about an application, such as
a call stack and start/stop times for any running methods. See Traceview: A Graphical Log Viewer for
information about reading trace files. To start logging trace files, call one
of the startMethodTracing() methods. To stop tracing, call
stopMethodTracing().
| Nested Classes | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Debug.InstructionCount | This class was deprecated in API level 23. Instruction counting is no longer supported. | ||||||||||
| Debug.MemoryInfo | This class is used to retrieved various statistics about the memory mappings for this process. | ||||||||||
| Constants | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| int | SHOW_CLASSLOADER | ||||||||||
| int | SHOW_FULL_DETAIL | Flags for printLoadedClasses(). | |||||||||
| int | SHOW_INITIALIZED | ||||||||||
| int | TRACE_COUNT_ALLOCS | This constant was deprecated in API level 23. Accurate counting is a burden on the runtime and may be removed. | |||||||||
| Public Methods | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
This method was deprecated
in API level 3.
no longer needed or useful
| |||||||||||
Dump "hprof" data to the specified file.
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Get a debugging dump of a system service by name.
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Enable "emulator traces", in which information about the current
method is made available to the "emulator -trace" feature.
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Returns the number of death notification links to Binder objects that
exist in the current process.
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Returns the number of active local Binder objects that exist in the
current process.
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Returns the number of references to remote proxy Binder objects that
exist in the current process.
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Returns the number of received transactions from the binder driver.
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Returns the number of sent transactions from this process.
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This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 11.
This method is now obsolete.
| |||||||||||
This method was deprecated
in API level 11.
This method is now obsolete.
| |||||||||||
This method was deprecated
in API level 11.
This method is now obsolete.
| |||||||||||
This method was deprecated
in API level 11.
This method is now obsolete.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
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Get the number of loaded classes.
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Retrieves information about this processes memory usages.
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Returns the amount of allocated memory in the native heap.
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Returns the amount of free memory in the native heap.
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Returns the size of the native heap.
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Retrieves the PSS memory used by the process as given by the
smaps.
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Returns the value of a particular runtime statistic or
null if no
such runtime statistic exists.
| |||||||||||
Returns a map of the names/values of the runtime statistics
that
getRuntimeStat(String) supports.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 11.
This method is now obsolete.
| |||||||||||
This method was deprecated
in API level 11.
This method is now obsolete.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
Determine if a debugger is currently attached.
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Dump a list of all currently loaded class to the log file.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 11.
This method is now obsolete.
| |||||||||||
This method was deprecated
in API level 11.
This method is now obsolete.
| |||||||||||
This method was deprecated
in API level 11.
This method is now obsolete.
| |||||||||||
This method was deprecated
in API level 11.
This method is now obsolete.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 11.
This method is now obsolete.
| |||||||||||
This method was deprecated
in API level 11.
This method is now obsolete.
| |||||||||||
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
This method was deprecated
in API level 11.
This method is now obsolete.
| |||||||||||
This method was deprecated
in API level 11.
This method is now obsolete.
| |||||||||||
This method was deprecated
in API level 18.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
Start method tracing, specifying the trace log file name.
| |||||||||||
Start method tracing with default log name and buffer size.
| |||||||||||
Start method tracing, specifying the trace log file name and the
buffer size.
| |||||||||||
Start method tracing, specifying the trace log file name and the
buffer size.
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Start sampling-based method tracing, specifying the trace log file name,
the buffer size, and the sampling interval.
| |||||||||||
Enable qemu tracing.
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This method was deprecated
in API level 18.
Accurate counting is a burden on the runtime and may be removed.
| |||||||||||
Stop method tracing.
| |||||||||||
Stop qemu tracing.
| |||||||||||
Get an indication of thread CPU usage.
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Wait until a debugger attaches.
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Returns "true" if one or more threads is waiting for a debugger
to attach.
| |||||||||||
|
[Expand]
Inherited Methods | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
From class
java.lang.Object
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Flags for printLoadedClasses(). Default behavior is to only show the class name.
This constant was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
Flags for startMethodTracing(). These can be ORed together. TRACE_COUNT_ALLOCS adds the results from startAllocCounting to the trace key file.
This method was deprecated
in API level 3.
no longer needed or useful
Change the JDWP port.
Dump "hprof" data to the specified file. This may cause a GC.
| fileName | Full pathname of output file (e.g. "/sdcard/dump.hprof"). |
|---|
| UnsupportedOperationException | if the VM was built without HPROF support. |
|---|---|
| IOException | if an error occurs while opening or writing files. |
Get a debugging dump of a system service by name.
Most services require the caller to hold android.permission.DUMP.
| name | of the service to dump |
|---|---|
| fd | to write dump output to (usually an output log file) |
| args | to pass to the service's dump method, may be null |
Enable "emulator traces", in which information about the current
method is made available to the "emulator -trace" feature. There
is no corresponding "disable" call -- this is intended for use by
the framework when tracing should be turned on and left that way, so
that traces captured with F9/F10 will include the necessary data.
This puts the VM into "profile" mode, which has performance
consequences.
To temporarily enable tracing, use startNativeTracing().
Returns the number of death notification links to Binder objects that exist in the current process.
Returns the number of active local Binder objects that exist in the current process.
Returns the number of references to remote proxy Binder objects that exist in the current process.
Returns the number of received transactions from the binder driver.
Returns the number of sent transactions from this process.
This method was deprecated
in API level 11.
This method is now obsolete.
This method exists for compatibility and always returns 0.
This method was deprecated
in API level 11.
This method is now obsolete.
This method exists for compatibility and always returns 0.
This method was deprecated
in API level 11.
This method is now obsolete.
This method exists for compatibility and always returns 0.
This method was deprecated
in API level 11.
This method is now obsolete.
This method exists for compatibility and has no effect.
Get the number of loaded classes.
Retrieves information about this processes memory usages. This information is broken down by how much is in use by dalivk, the native heap, and everything else.
Returns the amount of allocated memory in the native heap.
Returns the amount of free memory in the native heap.
Returns the size of the native heap.
Retrieves the PSS memory used by the process as given by the smaps.
Returns the value of a particular runtime statistic or null if no
such runtime statistic exists.
The following table lists the runtime statistics that the runtime supports. Note runtime statistics may be added or removed in a future API level.
| Runtime statistic name | Meaning | Example | Supported (API Levels) |
|---|---|---|---|
| art.gc.gc-count | The number of garbage collection runs. | 164 |
23 |
| art.gc.gc-time | The total duration of garbage collection runs in ms. | 62364 |
23 |
| art.gc.bytes-allocated | The total number of bytes that the application allocated. | 1463948408 |
23 |
| art.gc.bytes-freed | The total number of bytes that garbage collection reclaimed. | 1313493084 |
23 |
| art.gc.blocking-gc-count | The number of blocking garbage collection runs. | 2 |
23 |
| art.gc.blocking-gc-time | The total duration of blocking garbage collection runs in ms. | 804 |
23 |
| art.gc.gc-count-rate-histogram | Every 10 seconds, the gc-count-rate is computed as the number of garbage collection runs that have occurred over the last 10 seconds. art.gc.gc-count-rate-histogram is a histogram of the gc-count-rate samples taken since the process began. The histogram can be used to identify instances of high rates of garbage collection runs. For example, a histogram of "0:34503,1:45350,2:11281,3:8088,4:43,5:8" shows that most of the time there are between 0 and 2 garbage collection runs every 10 seconds, but there were 8 distinct 10-second intervals in which 5 garbage collection runs occurred. | 0:34503,1:45350,2:11281,3:8088,4:43,5:8 |
23 |
| art.gc.blocking-gc-count-rate-histogram | Every 10 seconds, the blocking-gc-count-rate is computed as the number of blocking garbage collection runs that have occurred over the last 10 seconds. art.gc.blocking-gc-count-rate-histogram is a histogram of the blocking-gc-count-rate samples taken since the process began. The histogram can be used to identify instances of high rates of blocking garbage collection runs. For example, a histogram of "0:99269,1:1,2:1" shows that most of the time there are zero blocking garbage collection runs every 10 seconds, but there was one 10-second interval in which one blocking garbage collection run occurred, and there was one interval in which two blocking garbage collection runs occurred. | 0:99269,1:1,2:1 |
23 |
| statName | the name of the runtime statistic to look up. |
|---|
Developers
null if the
runtime statistic doesn't exist.
Returns a map of the names/values of the runtime statistics
that getRuntimeStat(String) supports.
This method was deprecated
in API level 11.
This method is now obsolete.
This method exists for compatibility and has no effect.
This method was deprecated
in API level 11.
This method is now obsolete.
This method exists for compatibility and has no effect.
Determine if a debugger is currently attached.
Dump a list of all currently loaded class to the log file.
| flags | See constants above. |
|---|
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
Clears all the global and thread-local memory allocation counters.
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
Clears the global count of objects allocated.
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
Clears the global size of objects allocated.
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
Clears the count of classes initialized.
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
Clears the count of time spent initializing classes.
This method was deprecated
in API level 11.
This method is now obsolete.
This method exists for compatibility and has no effect.
This method was deprecated
in API level 11.
This method is now obsolete.
This method exists for compatibility and has no effect.
This method was deprecated
in API level 11.
This method is now obsolete.
This method exists for compatibility and has no effect.
This method was deprecated
in API level 11.
This method is now obsolete.
This method exists for compatibility and has no effect.
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
Clears the global count of objects freed.
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
Clears the global size of objects freed.
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
Clears the count of non-concurrent GC invocations.
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
Clears the thread-local count of objects allocated.
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
Clears the thread-local count of objects allocated.
This method was deprecated
in API level 11.
This method is now obsolete.
This method exists for compatibility and has no effect.
This method was deprecated
in API level 11.
This method is now obsolete.
This method exists for compatibility and has no effect.
This method was deprecated
in API level 23.
Accurate counting is a burden on the runtime and may be removed.
Clears the thread-local count of non-concurrent GC invocations.
This method was deprecated
in API level 11.
This method is now obsolete.
Establish an object allocation limit in the current thread. This feature was never enabled in release builds. The allocation limits feature was removed in Honeycomb. This method exists for compatibility and always returns -1 and has no effect.
This method was deprecated
in API level 11.
This method is now obsolete.
Establish a global object allocation limit. This feature was never enabled in release builds. The allocation limits feature was removed in Honeycomb. This method exists for compatibility and always returns -1 and has no effect.
This method was deprecated
in API level 18.
Accurate counting is a burden on the runtime and may be removed.
Start counting the number and aggregate size of memory allocations.
The start method resets the counts and enables counting.
The stop method disables the counting so that the analysis
code doesn't cause additional allocations. The various get methods return
the specified value. And the various reset methods reset the specified
count.
Counts are kept for the system as a whole (global) and for each thread. The per-thread counts for threads other than the current thread are not cleared by the "reset" or "start" calls.
Start method tracing, specifying the trace log file name. The trace file will be put under "/sdcard" unless an absolute path is given. See Traceview: A Graphical Log Viewer for information about reading trace files.
| traceName | Name for the trace log file to create.
If traceName is null, this value defaults to "/sdcard/dmtrace.trace".
If the files already exist, they will be truncated.
If the trace file given does not end in ".trace", it will be appended for you.
|
|---|
Start method tracing with default log name and buffer size. See Traceview: A Graphical Log Viewer for information about reading these files. Call stopMethodTracing() to stop tracing.
Start method tracing, specifying the trace log file name and the buffer size. The trace files will be put under "/sdcard" unless an absolute path is given. See Traceview: A Graphical Log Viewer for information about reading trace files.
When method tracing is enabled, the VM will run more slowly than
usual, so the timings from the trace files should only be considered
in relative terms (e.g. was run #1 faster than run #2). The times
for native methods will not change, so don't try to use this to
compare the performance of interpreted and native implementations of the
same method. As an alternative, consider using sampling-based method
tracing via startMethodTracingSampling(String, int, int) or
"native" tracing in the emulator via startNativeTracing().
| traceName | Name for the trace log file to create.
If traceName is null, this value defaults to "/sdcard/dmtrace.trace".
If the files already exist, they will be truncated.
If the trace file given does not end in ".trace", it will be appended for you. |
|---|---|
| bufferSize | The maximum amount of trace data we gather. If not given, it defaults to 8MB. |
| flags | Flags to control method tracing. The only one that is currently defined is TRACE_COUNT_ALLOCS.
|
Start method tracing, specifying the trace log file name and the buffer size. The trace files will be put under "/sdcard" unless an absolute path is given. See Traceview: A Graphical Log Viewer for information about reading trace files.
| traceName | Name for the trace log file to create.
If traceName is null, this value defaults to "/sdcard/dmtrace.trace".
If the files already exist, they will be truncated.
If the trace file given does not end in ".trace", it will be appended for you. |
|---|---|
| bufferSize | The maximum amount of trace data we gather. If not given, it defaults to 8MB. |
Start sampling-based method tracing, specifying the trace log file name, the buffer size, and the sampling interval. The trace files will be put under "/sdcard" unless an absolute path is given. See Traceview: A Graphical Log Viewer for information about reading trace files.
| traceName | Name for the trace log file to create.
If traceName is null, this value defaults to "/sdcard/dmtrace.trace".
If the files already exist, they will be truncated.
If the trace file given does not end in ".trace", it will be appended for you. |
|---|---|
| bufferSize | The maximum amount of trace data we gather. If not given, it defaults to 8MB. |
| intervalUs | The amount of time between each sample in microseconds. |
Enable qemu tracing. For this to work requires running everything inside
the qemu emulator; otherwise, this method will have no effect. The trace
file is specified on the command line when the emulator is started. For
example, the following command line
emulator -trace foo
will start running the emulator and create a trace file named "foo". This
method simply enables writing the trace records to the trace file.
The main differences between this and startMethodTracing() are
that tracing in the qemu emulator traces every cpu instruction of every
process, including kernel code, so we have more complete information,
including all context switches. We can also get more detailed information
such as cache misses. The sequence of calls is determined by
post-processing the instruction trace. The qemu tracing is also done
without modifying the application or perturbing the timing of calls
because no instrumentation is added to the application being traced.
One limitation of using this method compared to using
startMethodTracing() on the real device is that the emulator
does not model all of the real hardware effects such as memory and
bus contention. The emulator also has a simple cache model and cannot
capture all the complexities of a real cache.
This method was deprecated
in API level 18.
Accurate counting is a burden on the runtime and may be removed.
Stop counting the number and aggregate size of memory allocations.
Stop qemu tracing. See startNativeTracing() to start tracing.
Tracing can be started and stopped as many times as desired. When the qemu emulator itself is stopped then the buffered trace records are flushed and written to the trace file. In fact, it is not necessary to call this method at all; simply killing qemu is sufficient. But starting and stopping a trace is useful for examining a specific region of code.
Get an indication of thread CPU usage. The value returned indicates the amount of time that the current thread has spent executing code or waiting for certain types of I/O. The time is expressed in nanoseconds, and is only meaningful when compared to the result from an earlier call. Note that nanosecond resolution does not imply nanosecond accuracy. On system which don't support this operation, the call returns -1.
Wait until a debugger attaches. As soon as the debugger attaches, this returns, so you will need to place a breakpoint after the waitForDebugger() call if you want to start tracing immediately.
Returns "true" if one or more threads is waiting for a debugger to attach.