HashedWheelTimer Error using Akka and Couchbase

I am using Couchbase Scala SDK with akka. Every time I run my application, I get the following error in my logs after some time. Has anyone encountered the issue? Is there a way to resolve it?

[ERROR] [<timestamp>] [AkkaIq-akka.actor.default-dispatcher-<n>] [com.couchbase.client.core.deps.io.netty.util.HashedWheelTimer] You are creating too many HashedWheelTimer instances. HashedWheelTimer is a shared resource that must be reused across the JVM,so that only a few instances are created.


Hey @ali.parsaei

First, congratulations on asking what I believe is the first forum question on the new alpha Scala client :slight_smile:

The HashedWheelTimer is only created in a couple of places in the code - when you create a Cluster and when you create an Environment. Both of those should only be happening once per application, and my guess is that the application is creating multiple ones accidentally.

Hi @graham.pople,

Thanks for your help. I checked my code and noticed that I was calling cluster connection multiple times. I modified my code to lazily instantiate the connection instance only once which led to error message disappearing.

Glad to hear you got to the bottom of it @ali.parsaei

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