Issues about concurrent request to Trident DRPC

["JianJian, Bu" <ji...@amazon.com>]

Dear All,

We’re encountering some issue when use trident DRPC --  It seems that trident DRPC request is executed sequentially with later request blocked by previous one no matter how the parallelism parameter would be set.

Our usage is :  we setup a client faced web services  which is hosted by a group of hosts.   The web service receive requests from our client and call storm DRPC to query the data and send back the result to the
Client.

Now the issue is some of the request will take much time to be finished by DRPC.  So these requests will block other clients from getting the result.   I can see many introductions in storm wiki
about how drpc works but there is little threads about how drpc handles multiple requests.    There is only one sentence about the concurrent reuqests in this wiki https://storm.apache.org/documentation/Distributed-RPC.html  “KeyedFairBolt for weaving the processing of multiple requests at the same time” .  But it has little help.    There may be some ideas like start multiple similar topology in the same
cluster but I think that would have other issue like balance the load.  Does anyone ever have the similar issue and how did that get solved?