com.sleepycat.je.cleaner

Class UtilizationTracker

java.lang.Object

com.sleepycat.je.cleaner.BaseUtilizationTracker

com.sleepycat.je.cleaner.UtilizationTracker

public class UtilizationTracker
extends BaseUtilizationTracker

Tracks changes to the utilization profile since the last checkpoint. This is the "global" tracker for an environment that tracks changes as they occur in live operations. Other "local" tracker classes are used to count utilization locally and then later transfer the information to the global tracker, this tracker.

All changes to this object occur must under the log write latch. It is possible to read tracked info without holding the latch. This is done by the cleaner when selecting a file and by the checkpointer when determining what FileSummaryLNs need to be written. To read tracked info outside the log write latch, call getTrackedFile or getTrackedFiles.

Method Summary

Modifier and Type	Method and Description
void	countNewLogEntry(long lsn, LogEntryType type, int size) Counts the addition of all new log entries including LNs.
void	countObsoleteNode(long lsn, LogEntryType type, int size) Counts a node that has become obsolete and tracks the LSN offset, if non-zero, to avoid a lookup during cleaning.
void	countObsoleteNodeDupsAllowed(long lsn, LogEntryType type, int size) Counts as countObsoleteNode does, tracks the obsolete LSN offset, but does not fire an assert if the offset has already been counted.
void	countObsoleteNodeInexact(long lsn, LogEntryType type, int size) Counts as countObsoleteNode does, but since the LSN may be inexact, does not track the obsolete LSN offset.
long	evictMemory() Evicts tracked detail if the budget for the tracker is exceeded.
EnvironmentImpl	getEnvironment()
TrackedFileSummary	getUnflushableTrackedSummary(long fileNum) Returns a tracked summary for the given file which will not be flushed.

Methods inherited from class com.sleepycat.je.cleaner.BaseUtilizationTracker

countObsoleteDb, getTrackedFile, getTrackedFiles, isLNType, trackObsoleteInfo, transferToUtilizationTracker

Methods inherited from class java.lang.Object

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

Method Detail

getEnvironment

public EnvironmentImpl getEnvironment()

Overrides:

getEnvironment in class BaseUtilizationTracker

evictMemory

public long evictMemory()
                 throws DatabaseException

Evicts tracked detail if the budget for the tracker is exceeded. Evicts only one file summary LN at most to keep eviction batches small. Returns the number of bytes freed.

When flushFileSummary is called, the TrackedFileSummary is cleared via its reset method, which is called by FileSummaryLN.writeToLog. This is how memory is subtracted from the budget.

Throws:

DatabaseException

countNewLogEntry

public void countNewLogEntry(long lsn,
                             LogEntryType type,
                             int size)

Counts the addition of all new log entries including LNs.

Must be called under the log write latch.

countObsoleteNode

public void countObsoleteNode(long lsn,
                              LogEntryType type,
                              int size)

Counts a node that has become obsolete and tracks the LSN offset, if non-zero, to avoid a lookup during cleaning.

A zero LSN offset is used as a special value when obsolete offset tracking is not desired. [#15365] The file header entry (at offset zero) is never counted as obsolete, it is assumed to be obsolete by the cleaner.

This method should only be called for LNs and INs (i.e, only for nodes). If type is null we assume it is an LN.

Must be called under the log write latch.

countObsoleteNodeInexact

public void countObsoleteNodeInexact(long lsn,
                                     LogEntryType type,
                                     int size)

Counts as countObsoleteNode does, but since the LSN may be inexact, does not track the obsolete LSN offset.

This method should only be called for LNs and INs (i.e, only for nodes). If type is null we assume it is an LN.

Must be called under the log write latch.

countObsoleteNodeDupsAllowed

public void countObsoleteNodeDupsAllowed(long lsn,
                                         LogEntryType type,
                                         int size)

Counts as countObsoleteNode does, tracks the obsolete LSN offset, but does not fire an assert if the offset has already been counted. Use this method when the same LSN offset may be counted twice in certain circumstances.

This method should only be called for LNs and INs (i.e, only for nodes). If type is null we assume it is an LN.

Must be called under the log write latch.

getUnflushableTrackedSummary

public TrackedFileSummary getUnflushableTrackedSummary(long fileNum)

Returns a tracked summary for the given file which will not be flushed.