CP, Monitors | chuahou.dev

[9.2] Lower level primitives than channels.
[9.4] Mutual exclusion so that at most one of some ops performed at a time.
[9.6] Scala AnyRefs are monitors with obj.synchronized { ... } blocks.
- At most one thread active in a monitor’s synchronized block.
- [9.20] Suspended waiting with wait(), notify(), notifyAll().
  - [9.21] Beware spurious wake-ups. Use while (!cond) wait();
  - [9.24] Scala uses signal-and-continue (block with notify() completes first), vs signal-and-wait.
- [9.26] wait(t) with timeout t.
[10.6] CSO Monitors allow targeted notifications (but slower).
- [10.7] Condition to wait on with monitor.newCondition.
- await(), await(cond), signal(), signalAll() on Condition.
Fine-grained locking
- [9.10] Separate locks or [9.11] striped locking
- [9.12] Lock shards (disjoint subsets of object by hash) independently.
[9.14] Java Locks for explicit locking with lock(), unlock(), tryLock().
[10.24] Signals may be lost if notification sent before waiting.
- [10.25] Consider drawing sequence diagrams.
- [10.29] Use state variables (especially in quiescent/inactive states).