The benefits of Async stream readers in cache for stream storage:
The cache essentially projects portions of the stream so that the entire stream does not have to scanned from begin to end repeatedly. This mode of operation is different from finding popular stream segments across stream readers.
The cache may use a queue to hold contiguous segments from a stream.
The choice of queue is extremely important for peak throughput. The use of a lock free data structure as opposed to an ArrayBlockingQueue can do away with lock contention. The queues work satisfactorily until they are full. Garbage free Async stream readers have the best response time.
The benefits here are similar to LogAppenders except that they are on write path whole these are in read path.
Asynchronous read together with lock free access and skip level access boost performance. The cache may encounter significant size for each segment and a writer that transfers a segment over the network may take time in the order of hundreds of milliseconds. Instead, having a continuous background import for adjustable window of steam segments tremendously improves the load on the stream store while responding to seek requests on segments

Please refer to the discussion on caching context for stream managers with:

https://1drv.ms/w/s!Ashlm-Nw-wnWvBXkU9jz_Z2EXWLp

and  implementation where it is applicable with: https://github.com/ravibeta/JavaSamples/tree/master/logging