org.apache.hadoop.hbase.regionserver
Class ReadWriteConsistencyControl
java.lang.Object
org.apache.hadoop.hbase.regionserver.ReadWriteConsistencyControl
public class ReadWriteConsistencyControl
- extends Object
Manages the read/write consistency within memstore. This provides
an interface for readers to determine what entries to ignore, and
a mechanism for writers to obtain new write numbers, then "commit"
the new writes for readers to read (thus forming atomic transactions).
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
FIXED_SIZE
public static final long FIXED_SIZE
ReadWriteConsistencyControl
public ReadWriteConsistencyControl()
getThreadReadPoint
public static long getThreadReadPoint()
- Get this thread's read point. Used primarily by the memstore scanner to
know which values to skip (ie: have not been completed/committed to
memstore).
setThreadReadPoint
public static void setThreadReadPoint(long readPoint)
- Set the thread read point to the given value. The thread RWCC
is used by the Memstore scanner so it knows which values to skip.
Give it a value of 0 if you want everything.
resetThreadReadPoint
public static long resetThreadReadPoint(ReadWriteConsistencyControl rwcc)
- Set the thread RWCC read point to whatever the current read point is in
this particular instance of RWCC. Returns the new thread read point value.
resetThreadReadPoint
public static void resetThreadReadPoint()
- Set the thread RWCC read point to 0 (include everything).
beginMemstoreInsert
public ReadWriteConsistencyControl.WriteEntry beginMemstoreInsert()
completeMemstoreInsert
public void completeMemstoreInsert(ReadWriteConsistencyControl.WriteEntry e)
memstoreReadPoint
public long memstoreReadPoint()
Copyright © 2011 The Apache Software Foundation. All Rights Reserved.