Jan Ypma

Don't know how I missed that :-) Thanks a lot! By the way, works also fine with `bloop`: ``` bloop test myproject -o zio.ZIOSpec -- -t "replaceIfSummary" ```

@akka/akka-http-team tests green, ready for review.

I decided to re-use the existing timeout mostly for simplicity's sake (understanding client timeouts already is hard enough). We could introduce something like `queue-timeout`, and update the timeout docs page....

I'm working on a test and introduced the separate `queueTimeout`. I think I have a problem though: `PoolInterfaceActor` always gets an initial demand of 16 items from the downstream `PoolConductor`,...

Thanks for the extra review! I'm happy to address the remaining comments. However, @jrudolph, weren't you doing some re-write of the client pool stages that would make this irrelevant? Or...

I should note that this PR does not (fully) work: Because of the 16-item internal akka streams buffer, there will still be 16 items queued up that we can't purge....

This may also make issues like https://github.com/akka/akka-http/issues/843 and https://github.com/akka/akka-http/issues/1186 easier to debug, by showing how much is connected / queued up at any point in time.

@akka/akka-http-team tests green, ready for review.

@akka/akka-http-team Tests green. Anyone willing to take a look?

@jrudolph Let me know if you think this is going in the right direction.