Update runner threads

core/src/main/java/com/radixdlt/environment/rx/RxModuleRunnerImpl.java

@@ -64,8 +64,6 @@
 
 package com.radixdlt.environment.rx;
 
-import static java.util.concurrent.Executors.newSingleThreadScheduledExecutor;
-
 import com.google.common.collect.ImmutableList;
 import com.radixdlt.consensus.event.CoreEvent;
 import com.radixdlt.consensus.event.LocalEvent;
@@ -75,7 +73,6 @@
 import com.radixdlt.environment.RemoteEventProcessor;
 import com.radixdlt.environment.StartProcessor;
 import com.radixdlt.modules.ModuleRunner;
-import com.radixdlt.utils.ThreadFactories;
 import io.reactivex.rxjava3.core.Flowable;
 import io.reactivex.rxjava3.core.Observable;
 import io.reactivex.rxjava3.core.Scheduler;
@@ -86,6 +83,7 @@
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
+import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.TimeUnit;
 import java.util.function.Consumer;
@@ -193,17 +191,14 @@ public void start(Consumer<Throwable> errorHandler) {
         return;
       }
 
-      this.executorService =
-          newSingleThreadScheduledExecutor(ThreadFactories.daemonThreads(threadName));
-      var singleThreadScheduler = Schedulers.from(this.executorService);
+      this.executorService = Executors.newScheduledThreadPool(4);
+      var scheduler = Schedulers.from(this.executorService);
 
       logger.info("Starting Runner: {}", this.threadName);
 
       this.executorService.submit(() -> startProcessors.forEach(StartProcessor::start));
       final var disposables =
-          this.subscriptions.stream()
-              .map(s -> s.subscribe(singleThreadScheduler, errorHandler))
-              .toList();
+          this.subscriptions.stream().map(s -> s.subscribe(scheduler, errorHandler)).toList();
       this.compositeDisposable = new CompositeDisposable(disposables);
 
       this.onStart.forEach(f -> f.accept(this.executorService));