# When starting worker, get the Potential Deadlock error, can anyone suggest? **URL:** \ **Category:** Community Support\ **Created:** [March 26, 2021, 7:00am UTC](https://community.temporal.io/t/when-starting-worker-get-the-potential-deadlock-error-can-anyone-suggest/1821 "2021-03-26T07:00:11Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Yang\_Yu](https://sea2.discourse-cdn.com/flex016/user_avatar/community.temporal.io/yang_yu/32/743_2.png) [@Yang\_Yu](https://community.temporal.io/u/Yang_Yu)\ **Post date:** [March 26, 2021, 7:00am UTC](https://community.temporal.io/t/when-starting-worker-get-the-potential-deadlock-error-can-anyone-suggest/1821/1 "2021-03-26T07:00:11Z")
Getting the following error when starting a worker program: I:/projects/golangworkspace/pkg/mod/go.temporal.io/sdk@v1.4.1/internal/internal\_worker\_base.go:270 +0x106 2021/03/26 14:58:58 WARN Failed to process workflow task. Namespace default TaskQueue ml\_activity WorkerID 19832@WSG126024@ WorkflowType MLDemoWorkflow WorkflowID ml\_demo\_cff99062-9eec-4547-ac2b-8fe6b8080f14 RunID db5bcc2f-257c-4006-8900-19aef562f2da Attempt 20 Error Potential deadlock detected: workflow goroutine “root” didn’t yield for over a second 2021/03/26 14:59:09 ERROR Workflow panic Namespace default TaskQueue ml\_activity WorkerID 19832@WSG126024@ WorkflowType MLDemoWorkflow WorkflowID ml\_demo\_cff99062-9eec-4547-ac2b-8fe6b8080f14 RunID db5bcc2f-257c-4006-8900-19aef562f2da Attempt 21 Error Potential deadlock detected: workflow goroutine “root” didn’t yield for over a second StackTrace process event for ml\_activity [panic]: [go.temporal.io/sdk/internal.(\*coroutineState](http://go.temporal.io/sdk/internal.(*coroutineState)).call(0xc0005dd220) I:/projects/golangworkspace/pkg/mod/go.temporal.io/sdk@v1.4.1/internal/internal\_workflow.go:881 +0x1eb [go.temporal.io/sdk/internal.(\*dispatcherImpl](http://go.temporal.io/sdk/internal.(*dispatcherImpl)).ExecuteUntilAllBlocked(0xc0005dd1d0, 0x0, 0x0) I:/projects/golangworkspace/pkg/mod/go.temporal.io/sdk@v1.4.1/internal/internal\_workflow.go:966 +0x30b [go.temporal.io/sdk/internal.executeDispatcher](http://go.temporal.io/sdk/internal.executeDispatcher)(0xf19ad0, 0xc0005eed00, 0xf1d368, 0xc0005dd1d0) I:/projects/golangworkspace/pkg/mod/go.temporal.io/sdk@v1.4.1/internal/internal\_workflow.go:569 +0xb8 [go.temporal.io/sdk/internal.(\*syncWorkflowDefinition](http://go.temporal.io/sdk/internal.(*syncWorkflowDefinition)).OnWorkflowTaskStarted(0xc0005eec80) I:/projects/golangworkspace/pkg/mod/go.temporal.io/sdk@v1.4.1/internal/internal\_workflow.go:542 +0x51 [go.temporal.io/sdk/internal.(\*workflowExecutionEventHandlerImpl](http://go.temporal.io/sdk/internal.(*workflowExecutionEventHandlerImpl)).ProcessEvent(0xc0005e5128, 0xc000053580, 0x100, 0x0, 0x0) I:/projects/golangworkspace/pkg/mod/go.temporal.io/sdk@v1.4.1/internal/internal\_event\_handlers.go:791 +0x3b8 [go.temporal.io/sdk/internal.(\*workflowExecutionContextImpl](http://go.temporal.io/sdk/internal.(*workflowExecutionContextImpl)).ProcessWorkflowTask(0xc0001a7050, 0xc0000e6090, 0x13f3880, 0xc0004aed90, 0xc0001a7050, 0x0) I:/projects/golangworkspace/pkg/mod/go.temporal.io/sdk@v1.4.1/internal/internal\_task\_handlers.go:876 +0x72c [go.temporal.io/sdk/internal.(\*workflowTaskHandlerImpl](http://go.temporal.io/sdk/internal.(*workflowTaskHandlerImpl)).ProcessWorkflowTask(0xc000215550, 0xc0000e6090, 0xc0005fbaa0, 0x0, 0x0, 0x0, 0x0) I:/projects/golangworkspace/pkg/mod/go.temporal.io/sdk@v1.4.1/internal/internal\_task\_handlers.go:727 +0x6f9 [go.temporal.io/sdk/internal.(\*workflowTaskPoller](http://go.temporal.io/sdk/internal.(*workflowTaskPoller)).processWorkflowTask(0xc000272ea0, 0xc0000e6090, 0x0, 0x0) I:/projects/golangworkspace/pkg/mod/go.temporal.io/sdk@v1.4.1/internal/internal\_task\_pollers.go:288 +0x4c2 [go.temporal.io/sdk/internal.(\*workflowTaskPoller](http://go.temporal.io/sdk/internal.(*workflowTaskPoller)).ProcessTask(0xc000272ea0, 0xcc6600, 0xc0000e6090, 0xc000251b90, 0xc0005dc5f0) I:/projects/golangworkspace/pkg/mod/go.temporal.io/sdk@v1.4.1/internal/internal\_task\_pollers.go:259 +0x8b [go.temporal.io/sdk/internal.(\*baseWorker](http://go.temporal.io/sdk/internal.(*baseWorker)).processTask(0xc000446000, 0xcc61c0, 0xc000075490) I:/projects/golangworkspace/pkg/mod/go.temporal.io/sdk@v1.4.1/internal/internal\_worker\_base.go:343 +0xc4 created by [go.temporal.io/sdk/internal.(\*baseWorker](http://go.temporal.io/sdk/internal.(*baseWorker)).runTaskDispatcher I:/projects/golangworkspace/pkg/mod/go.temporal.io/sdk@v1.4.1/internal/internal\_worker\_base.go:270 +0x106 2021/03/26 14:59:09 WARN Failed to process workflow task. Namespace default TaskQueue ml\_activity WorkerID 19832@WSG126024@ WorkflowType MLDemoWorkflow WorkflowID ml\_demo\_cff99062-9eec-4547-ac2b-8fe6b8080f14 RunID db5bcc2f-257c-4006-8900-19aef562f2da Attempt 21 Error Potential deadlock detected: workflow goroutine “root” didn’t yield for over a second 2021/03/26 14:59:13 INFO Worker has been stopped. Namespace default TaskQueue ml\_activity WorkerID 19832@WSG126024@ Signal interrupt 2021/03/26 14:59:13 INFO Stopped Worker Namespace default TaskQueue ml\_activity WorkerID 19832@WSG126024@ This program has been working, anyone has suggestions how to resolve this? ---
**Author:** ![maxim](https://sea2.discourse-cdn.com/flex016/user_avatar/community.temporal.io/maxim/32/8_2.png) [@maxim](https://community.temporal.io/u/maxim)\ **Post date:** [March 26, 2021, 3:45pm UTC](https://community.temporal.io/t/when-starting-worker-get-the-potential-deadlock-error-can-anyone-suggest/1821/2 "2021-03-26T15:45:47Z")
It looks like your workflow code invokes some blocking function which is not part of the Temporal SDK APIs. ---
**Author:** ![Yang\_Yu](https://sea2.discourse-cdn.com/flex016/user_avatar/community.temporal.io/yang_yu/32/743_2.png) [@Yang\_Yu](https://community.temporal.io/u/Yang_Yu)\ **Post date:** [March 29, 2021, 3:44am UTC](https://community.temporal.io/t/when-starting-worker-get-the-potential-deadlock-error-can-anyone-suggest/1821/3 "2021-03-29T03:44:05Z")
Thanks. This is resolved, I put a 5 second sleep in the workflow code for testing purpose. So does this mean we cannot have any local execution that blocks for longer than x seconds in Temporal workflow code? ---
**Author:** ![maxim](https://sea2.discourse-cdn.com/flex016/user_avatar/community.temporal.io/maxim/32/8_2.png) [@maxim](https://community.temporal.io/u/maxim)\ **Post date:** [March 29, 2021, 3:47pm UTC](https://community.temporal.io/t/when-starting-worker-get-the-potential-deadlock-error-can-anyone-suggest/1821/4 "2021-03-29T15:47:34Z")
> So does this mean we cannot have any local execution that blocks for longer than x seconds in Temporal workflow code? Correct. That would be a bad idea as workflow uses replay for recovery and such CPU intensive task would be reexecuted multiple times. You can always use local activities to execute a code that needs to block due to IO locally. ---
**Author:** ![Yang\_Yu](https://sea2.discourse-cdn.com/flex016/user_avatar/community.temporal.io/yang_yu/32/743_2.png) [@Yang\_Yu](https://community.temporal.io/u/Yang_Yu)\ **Post date:** [March 30, 2021, 2:09am UTC](https://community.temporal.io/t/when-starting-worker-get-the-potential-deadlock-error-can-anyone-suggest/1821/5 "2021-03-30T02:09:07Z")
@maxim thanks for the explaination.