Other Scenario Ideas

[jamesward]

Batching - 50 requests, batched into groups of 10
Retry

[cowboyd]

here are some ideas!

Sliding Window

Server allows a max of 10 open requests at a time; new requests may only be made after existing ones have returned. Client should "slide" through 1000 requests in this way. Having 11 open requests at a time is an immediate failure.

Sliding Window + timeout

Same as sliding window, but server will randomly hang on certain requests. Client must not overrun the window, but also gracefully cancel hung requests.

[jamesward]

Those are great! Thanks for the ideas.

[jabrena]

Another idea could be:

• Implicit/Explicit cancellation for Heavy weight request and the implications with Clients involved.

[jamesward]

Another idea: Something that can show ScopedValue / some thread local state. Not sure what that'd be though.

[jypma]

One aspect that I'd like to see investigated further is synchronization of cancellation during races. In other words, when doing effect1.race(effect2).andThen(effect3), do we have the guarantee that effect1 and effect2 have either completed or are done cancelling, when effect3 starts. This is perhaps related to what @jabrena is suggesting, too.

This is a hard topic, dating back to java's Thread.stop being deprecated, CompletableFuture.cancel not promising anything, and many Future classes not having cancel in the first place. So it'd be interesting to add! :)

[jabrena]

You are right @jypma, cancellation is a topic which developers doesn´t put so much attention. Indeed @jamesward mentioned in one conversation. It could be a good challenge. :)

• https://github.com/openjdk/jdk/blob/master/src/java.base/share/classes/java/util/concurrent/CancellationException.java
• https://github.com/openjdk/jdk/blob/master/src/java.base/share/classes/java/util/concurrent/CompletableFuture.java
• https://github.com/openjdk/jdk/blob/master/src/java.net.http/share/classes/java/net/http/HttpClient.java
• https://github.com/openjdk/jdk/blob/master/src/java.base/share/classes/java/util/concurrent/StructuredTaskScopeImpl.java

[jabrena]

The Scenario 3, offer several opportunities:

• Bounded concurrency
• Dynamic Headroom