virajjasani commented on code in PR #4468:
URL: https://github.com/apache/hbase/pull/4468#discussion_r885112060
##########
hbase-server/src/main/java/org/apache/hadoop/hbase/master/normalizer/RegionNormalizerWorkQueue.java:
##########
@@ -39,62 +39,22 @@
* {@link BlockingQueue}.</li>
* <li>Allows a producer to insert an item at the head of the queue, if
desired.</li>
* </ul>
- * Assumes low-frequency and low-parallelism concurrent access, so protects
state using a simplistic
- * synchronization strategy.
*/
@InterfaceAudience.Private
class RegionNormalizerWorkQueue<E> {
/** Underlying storage structure that gives us the Set behavior and FIFO
retrieval policy. */
private LinkedHashSet<E> delegate;
- // the locking structure used here follows the example found in
LinkedBlockingQueue. The
- // difference is that our locks guard access to `delegate` rather than the
head node.
-
- /** Lock held by take, poll, etc */
- private final ReentrantLock takeLock;
-
+ /** Lock for puts and takes **/
+ private final ReentrantReadWriteLock lock;
/** Wait queue for waiting takes */
private final Condition notEmpty;
- /** Lock held by put, offer, etc */
- private final ReentrantLock putLock;
-
RegionNormalizerWorkQueue() {
delegate = new LinkedHashSet<>();
- takeLock = new ReentrantLock();
- notEmpty = takeLock.newCondition();
- putLock = new ReentrantLock();
- }
-
- /**
- * Signals a waiting take. Called only from put/offer (which do not
otherwise ordinarily lock
- * takeLock.)
- */
- private void signalNotEmpty() {
- final ReentrantLock takeLock = this.takeLock;
- takeLock.lock();
- try {
- notEmpty.signal();
- } finally {
- takeLock.unlock();
- }
- }
-
- /**
- * Locks to prevent both puts and takes.
- */
- private void fullyLock() {
- putLock.lock();
- takeLock.lock();
- }
-
- /**
- * Unlocks to allow both puts and takes.
- */
- private void fullyUnlock() {
- takeLock.unlock();
- putLock.unlock();
+ lock = new ReentrantReadWriteLock();
+ notEmpty = lock.writeLock().newCondition();
Review Comment:
Basically we are changing notEmpty from being readLock Condition to
writeLock Condition, this seems good.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
