On Fri, 30 Jun 2023 19:38:19 GMT, Doug Lea <d...@openjdk.org> wrote:
>> This now uses Thread.isVirtual to distinguish spin vs immediate block cases,
>> enabling re-introduction of spin control from the previous version, removing
>> anomalies like this one.
>
> Doug Lea has updated the pull request incrementally with one additional
> commit since the last revision:
>
> Fix inverted test assert; improve internal documentation; simplify code
src/java.base/share/classes/java/util/concurrent/LinkedTransferQueue.java line
144:
> 142: * nodes, CASing from null to a data value. (To reduce the need
> 143: * for re-reads, we use the compareAndExchange forms of CAS for
> 144: * pointer updates, that provide the current value to comtinue
Suggestion:
* pointer updates, that provide the current value to continue
src/java.base/share/classes/java/util/concurrent/LinkedTransferQueue.java line
158:
> 156: * suffix of zero or more unmatched nodes. Note that we allow both
> 157: * the prefix and suffix to be zero length, which in turn means
> 158: * that we do not require a dummy header.
@DougLea Great to avoid having the dummy header 👍
src/java.base/share/classes/java/util/concurrent/LinkedTransferQueue.java line
484:
> 482: * be at least 4.
> 483: */
> 484: private static final int MAX_SLACK = 1 << 7;
@DougLea Any guidance on how to tune this parameter? 🤔
src/java.base/share/classes/java/util/concurrent/LinkedTransferQueue.java line
570:
> 568: boolean haveData = (e != null);
> 569: TransferNode p; // current traversal node
> 570: TransferNode s = null; // the enqueued npde, if
> needed
Suggestion:
TransferNode s = null; // the enqueued node, if needed
src/java.base/share/classes/java/util/concurrent/SynchronousQueue.java line 133:
> 131: * compareAndExchange form of CAS for pointer updates to reduce
> 132: * memory traffic. The Fifo version accommodates lazy
> 133: * updates and slack as desxcribed in the LinkedTransferQueue
Suggestion:
* updates and slack as described in the LinkedTransferQueue
src/java.base/share/classes/java/util/concurrent/SynchronousQueue.java line 136:
> 134: * internal documentation.
> 135: * 2. SynchronousQueues must block threads waiting to become
> 136: * fulfilled, preceded by brief spins at/mear front positions
Suggestion:
* fulfilled, preceded by brief spins at/near front positions
src/java.base/share/classes/java/util/concurrent/SynchronousQueue.java line 148:
> 146: /**
> 147: * Extension of LinkedTransferQueue to support Lifo (stack) mode.
> 148: * Methods use tha "tail" field as top of stack (versus tail of
Suggestion:
* Methods use the "tail" field as top of stack (versus tail of
src/java.base/share/classes/java/util/concurrent/SynchronousQueue.java line 149:
> 147: * Extension of LinkedTransferQueue to support Lifo (stack) mode.
> 148: * Methods use tha "tail" field as top of stack (versus tail of
> 149: * queue). Note that popped nodes are not self-linked because thay
Suggestion:
* queue). Note that popped nodes are not self-linked because they
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/14317#discussion_r1250693753
PR Review Comment: https://git.openjdk.org/jdk/pull/14317#discussion_r1250699320
PR Review Comment: https://git.openjdk.org/jdk/pull/14317#discussion_r1255848871
PR Review Comment: https://git.openjdk.org/jdk/pull/14317#discussion_r1251121355
PR Review Comment: https://git.openjdk.org/jdk/pull/14317#discussion_r1250629998
PR Review Comment: https://git.openjdk.org/jdk/pull/14317#discussion_r1250630384
PR Review Comment: https://git.openjdk.org/jdk/pull/14317#discussion_r1250637093
PR Review Comment: https://git.openjdk.org/jdk/pull/14317#discussion_r1250637972
