ScalaPB worker crashing with Stream closed errors

[bjchambers]

Sometimes when running (especially in CircleCI), the bazel bulid fails with errors like the following. Are there any known issues with the ScalaPB worker that could be causing this? Any fixes / more information that would be helpful to collect?

INFO: From ScalaProtoCompile <elided>/api/tmp/state_scala_proto:
protoc-jar: protoc version: 3.8.0, detected platform: linux-x86_64 (linux/amd64)
protoc-jar: embedded: bin/3.8.0/protoc-3.8.0-linux-x86_64.exe
protoc-jar: executing: [/tmp/protocjar10815344638873208356/bin/protoc.exe, --plugin=protoc-gen-scala=/tmp/protocbridge9316711168667304922, --scala_out=grpc,flat_package:bazel-out/k8-fastbuild/bin/<elided>.proto, --proto_path=external/com_google_protobuf_wkt, --proto_path=external/com_github_scalapb, --proto_path=., <elided>proto, external/com_github_scalapb/scalapb/scalapb.proto, external/com_google_protobuf_wkt/google/protobuf/descriptor.proto]
ERROR: <elided>/BUILD:285:1: ScalaProtoCompile <elided>/value_scala_proto failed: Worker process quit or closed its stdin stream when we tried to send a WorkRequest:

---8<---8<--- Exception details ---8<---8<---
java.io.IOException: Stream closed
	at java.base/java.lang.ProcessBuilder$NullOutputStream.write(Unknown Source)
	at java.base/java.io.OutputStream.write(Unknown Source)
	at java.base/java.io.BufferedOutputStream.flushBuffer(Unknown Source)
	at java.base/java.io.BufferedOutputStream.flush(Unknown Source)
	at com.google.devtools.build.lib.worker.WorkerSpawnRunner.execInWorker(WorkerSpawnRunner.java:331)
	at com.google.devtools.build.lib.worker.WorkerSpawnRunner.actuallyExec(WorkerSpawnRunner.java:172)
	at com.google.devtools.build.lib.worker.WorkerSpawnRunner.exec(WorkerSpawnRunner.java:121)
	at com.google.devtools.build.lib.exec.SpawnRunner.execAsync(SpawnRunner.java:225)
	at com.google.devtools.build.lib.exec.AbstractSpawnStrategy.exec(AbstractSpawnStrategy.java:123)
	at com.google.devtools.build.lib.exec.AbstractSpawnStrategy.exec(AbstractSpawnStrategy.java:88)
	at com.google.devtools.build.lib.actions.SpawnActionContext.beginExecution(SpawnActionContext.java:41)
	at com.google.devtools.build.lib.exec.ProxySpawnActionContext.beginExecution(ProxySpawnActionContext.java:60)
	at com.google.devtools.build.lib.actions.SpawnContinuation$1.execute(SpawnContinuation.java:80)
	at com.google.devtools.build.lib.analysis.actions.SpawnAction$SpawnActionContinuation.execute(SpawnAction.java:1344)
	at com.google.devtools.build.lib.analysis.actions.SpawnAction.beginExecution(SpawnAction.java:314)
	at com.google.devtools.build.lib.actions.Action.execute(Action.java:123)
	at com.google.devtools.build.lib.skyframe.SkyframeActionExecutor$4.execute(SkyframeActionExecutor.java:851)
	at com.google.devtools.build.lib.skyframe.SkyframeActionExecutor$ActionRunner.continueAction(SkyframeActionExecutor.java:985)
	at com.google.devtools.build.lib.skyframe.SkyframeActionExecutor$ActionRunner.run(SkyframeActionExecutor.java:957)
	at com.google.devtools.build.lib.skyframe.ActionExecutionState.runStateMachine(ActionExecutionState.java:116)
	at com.google.devtools.build.lib.skyframe.ActionExecutionState.getResultOrDependOnFuture(ActionExecutionState.java:77)
	at com.google.devtools.build.lib.skyframe.SkyframeActionExecutor.executeAction(SkyframeActionExecutor.java:577)
	at com.google.devtools.build.lib.skyframe.ActionExecutionFunction.checkCacheAndExecuteIfNeeded(ActionExecutionFunction.java:760)
	at com.google.devtools.build.lib.skyframe.ActionExecutionFunction.compute(ActionExecutionFunction.java:275)
	at com.google.devtools.build.skyframe.AbstractParallelEvaluator$Evaluate.run(AbstractParallelEvaluator.java:451)
	at com.google.devtools.build.lib.concurrent.AbstractQueueVisitor$WrappedRunnable.run(AbstractQueueVisitor.java:399)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
	at java.base/java.lang.Thread.run(Unknown Source)
---8<---8<--- End of exception details ---8<---8<---

---8<---8<--- Start of log, file at /workspace/.bazel/bazel-workers/worker-3-ScalaProtoCompile.log ---8<---8<---
(empty)
---8<---8<--- End of log ---8<---8<---