Class Storage

java.lang.Object

io.perfmark.impl.Storage

public final class Storage
extends Object

Storage is responsible for storing and returning recorded marks. This is a low level class and not intended for use by users. Instead, the TraceEventWriter and TraceEventViewer classes provide easier to use APIs for accessing PerfMark data.

This code is NOT API stable, and may be removed in the future, or changed without notice.

Field Summary

Fields

Modifier and Type	Field	Description
private static final ConcurrentMap<Object, Reference<MarkHolder>>	allMarkHolders

Constructor Summary

Constructors

Modifier	Constructor	Description
private	Storage()

Method Summary

Modifier and Type	Method	Description
static long	getInitNanoTime()
static List<MarkList>	read()	Returns a list of MarkLists across all reachable threads.
static MarkList	readForTest()	May Return null.
static void	registerMarkHolder(MarkHolder markHolder)	Note: it is the responsibility of the caller to keep a strong reference to the markHolder.
static void	resetForAll()	Removes the global Read index on all storage, but leaves local storage in place.
static void	resetForThread()	Removes all data for the calling Thread.
static void	unregisterMarkHolder(MarkHolder markHolder)	This method is meant to aid in cleanup.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

allMarkHolders

private static final ConcurrentMap<Object, Reference<MarkHolder>> allMarkHolders

Constructor Details

Storage

private Storage()

Method Details

getInitNanoTime

public static long getInitNanoTime()

read

public static List<MarkList> read()

Returns a list of MarkLists across all reachable threads. MarkLists with no Marks may be removed.

Returns:

all reachable MarkLists.

resetForThread

public static void resetForThread()

Removes all data for the calling Thread. Other threads may Still have stored data.

resetForAll

public static void resetForAll()

Removes the global Read index on all storage, but leaves local storage in place. Because writer threads may still be writing to the same buffer (which they have a strong ref to), this function only removed data that is truly unwritable anymore. In addition, it captures a timestamp to which marks to include when reading. Thus, the data isn't fully removed. To fully remove all data, each tracing thread must call resetForThread().

registerMarkHolder

public static void registerMarkHolder(MarkHolder markHolder)

Note: it is the responsibility of the caller to keep a strong reference to the markHolder.

unregisterMarkHolder

public static void unregisterMarkHolder(MarkHolder markHolder)

This method is meant to aid in cleanup. It is not efficient so don't use it in production.

readForTest

public static MarkList readForTest()

May Return null.