How to set WorkerOptions in Go

Create an instance of Options from the go.temporal.io/sdk/worker package, set any of the optional fields, and pass the instance to the New call.

Field	Required	Type
MaxConcurrentActivityExecutionSize	No	int
WorkerActivitiesPerSecond	No	float64
MaxConcurrentLocalActivityExecutionSize	No	int
WorkerLocalActivitiesPerSecond	No	float64
TaskQueueActivitiesPerSecond	No	float64
MaxConcurrentActivityTaskPollers	No	int
MaxConcurrentWorkflowTaskExecutionSize	No	int
MaxConcurrentWorkflowTaskPollers	No	int
EnableLoggingInReplay	No	bool
DisableStickyExecution	No	bool
StickyScheduleToStartTimeout	No	time.Duration
BackgroundActivityContext	No	context.Context
WorkflowPanicPolicy	No	WorkflowPanicPolicy
WorkerStopTimeout	No	time.Duration
EnableSessionWorker	No	bool
MaxConcurrentSessionExecutionSize	No	int
WorkflowInterceptorChainFactories	No	[]WorkflowInterceptor
LocalActivityWorkerOnly	No	bool
Identity	No	string
DeadlockDetectionTimeout	No	time.Duration

MaxConcurrentActivityExecutionSize

Sets the maximum concurrent Activity Executions for the Worker.

• Type: int
• Default: 1000

A value of 0 sets to the default.

// ...
workerOptions := worker.Options{
  MaxConcurrentActivityExecutionSize: 1000,
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

WorkerActivitiesPerSecond

Rate limits the number of Activity Task Executions started per second for the Worker.

• Type: float64
• Default: 100000

A value of 0 sets to the default.

Intended use case is to limit resources used by the Worker.

Notice that the value type is a float so that the value can be less than 1 if needed. For example, if set to 0.1, Activity Task Executions will happen once every ten seconds. This can be used to protect down stream services from flooding with requests.

// ...
workerOptions := worker.Options{
    WorkerActivitiesPerSecond: 100000,
  // ..
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

MaxConcurrentLocalActivityExecutionSize

Set the maximum concurrent Local Activity Executions for the Worker.

• Type: int
• Default: 1000

A value of 0 sets to the default value.

// ...
workerOptions := worker.Options{
    MaxConcurrentLocalActivityExecutionSize: 1000,
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

WorkerLocalActivitiesPerSecond

Rate limits the number of Local Activity Executions per second executed for the Worker.

• Type: float64
• Default: 100000

A value of 0 sets to the default value.

Intended use case is to limit resources used by the Worker.

Notice that the value type is a float so that the value can be less than 1 if needed. For example, if set to 0.1, Local Activity Task Executions will happen once every ten seconds. This can be used to protect down stream services from flooding with requests.

// ...
workerOptions := worker.Options{
    WorkerLocalActivitiesPerSecond: 100000,
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

TaskQueueActivitiesPerSecond

Rate limits the number of Activity Executions that can be started per second.

• Type: float64
• Default: 100000

A value of 0 sets to the default value.

This rate is managed by the Temporal Cluster and limits the Activity Tasks per second for the entire Task Queue. This is in contrast to WorkerActivityTasksPerSecond controls activities only per Worker.

Notice that the number is represented in float, so that you can set it to less than 1 if needed. For example, set the number to 0.1 means you want your Activity to be executed once for every 10 seconds. This can be used to protect down stream services from flooding.

// ...
workerOptions := worker.Options{
    TaskQueueActivitiesPerSecond: 100000,
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

MaxConcurrentActivityTaskPollers

Sets the maximum number of goroutines to concurrently poll the Task Queue for Activity Tasks.

• Type: int
• Default: 2

Changing this value will affect the rate at which the Worker is able to consume Activity Tasks from the Task Queue.

// ...
workerOptions := worker.Options{
    MaxConcurrentActivityTaskPollers: 2,
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

MaxConcurrentWorkflowTaskExecutionSize

Sets the maximum number of concurrent Workflow Task Executions the Worker can have.

• Type: int
• Default: 1000

A value of 0 sets to the default value.

// ...
workerOptions := worker.Options{
    MaxConcurrentWorkflowTaskExecutionSize: 1000,
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

MaxConcurrentWorkflowTaskPollers

Sets the maximum number of goroutines that will concurrently poll the Task Queue for Workflow Tasks.

• Type: int
• Default: 2

Changing this value will affect the rate at which the Worker is able to consume Workflow Tasks from the Task Queue.

// ...
workerOptions := worker.Options{
    MaxConcurrentWorkflowTaskPollers: 2,
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

EnableLoggingInReplay

Set to enable logging in Workflow Execution replays.

• type: bool
• Default: false

In Workflow Definitions you can use workflow.GetLogger(ctx) to write logs. By default, the logger will skip logging during replays, so you do not see duplicate logs.

This is only really useful for debugging purpose.

// ...
workerOptions := worker.Options{
    EnableLoggingInReplay: false,
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

DisableStickyExecution

Deprecated

When DisableStickyExecution is true it can harm performance. It will be removed soon. See SetStickyWorkflowCacheSize instead.

Set to disable Sticky Executions

• Type: bool
• Default: false

Sticky Execution runs Workflow Tasks of a Workflow Execution on same host (could be a different Worker, as long as it is on the same host). This is an optimization for Workflow Executions. When sticky execution is enabled, Worker keeps the Workflow state in memory. New Workflow Task contains the new history events will be dispatched to the same Worker. If this Worker crashes, the sticky Workflow Task will timeout after StickyScheduleToStartTimeout, and Temporal Cluster will clear the stickiness for that Workflow Execution and automatically reschedule a new Workflow Task that is available for any Worker to pick up and resume the progress.

// ...
workerOptions := worker.Options{
    StickyScheduleToStartTimeout: time.Second(5),
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

StickyScheduleToStartTimeout

Sets the Sticky Execution Schedule-To-Start Timeout for Workflow Tasks.

• Type: time.Duration
• Default value is 5

The resolution is in seconds.

// ...
workerOptions := worker.Options{
    StickyScheduleToStartTimeout: time.Second(5),
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

BackgroundActivityContext

Not recommended

This method of passing dependencies between Activity Task Executions is not recommended anymore.

Instead, we recommend using a struct with fields that contain dependencies and develop Activity Definitions as struct methods and then pass all the dependencies on the structure initialization.

• Type: context.Context

Sets the background context.Context for all Activity Types registered with the Worker.

The context can be used to pass external dependencies such as database connections to Activity Task Executions.

// ...
ctx := context.WithValue(context.Background(), "your-key", "your-value")
workerOptions := worker.Options{
    BackgroundActivityContext: ctx,
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

WorkflowPanicPolicy

Sets how the Workflow Worker handles a non-deterministic Workflow Execution History Event and other panics from Workflow Definition code.

• Type: WorkflowPanicPolicy
• Default: BlockWorkflow

// ...
workerOptions := worker.Options{
    DisableStickyExecution: internal.BlockWorkflow,
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

WorkerStopTimeout

Sets the Worker's graceful stop timeout

• Type: time.Duration
• Default: 0

Value resolution is in seconds.

// ...
workerOptions := worker.Options{
    WorkerStopTimeout: time.Second(0),
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

EnableSessionWorker

Enables Sessions for Activity Workers.

• Type: bool
• Default: false

When true the Activity Worker creates a Session to sequentially process Activity Tasks for the given Task Queue.

// ...
workerOptions := worker.Options{
    EnableSessionWorker: true,
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

MaxConcurrentSessionExecutionSize

Sets the maximum number of concurrent Sessions that the Worker can support.

• Type: int
• Default: 1000

// ...
workerOptions := worker.Options{
    MaxConcurrentSessionExecutionSize: 1000,
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

WorkflowInterceptorChainFactories

Specifies the factories used to instantiate the Workflow interceptor chain.

• Type: []WorkflowInterceptor

The chain is instantiated for each replay of a Workflow Execution.

LocalActivityWorkerOnly

Sets the Worker to only handle Workflow Tasks and local Activity Tasks.

• Type: bool
• Default: false

// ...
workerOptions := worker.Options{
    LocalActivityWorkerOnly: 1000,
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

Identity

Sets the Temporal Client-level Identity value, overwriting the existing one.

• Type: string
• Default: client identity

// ...
workerOptions := worker.Options{
    Identity: "your_custom_identity",
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...

DeadlockDetectionTimeout

Sets the maximum time that a Workflow Task can execute for.

• Type: time.Duration
• Default: 1

Resolution is in seconds.

// ...
workerOptions := worker.Options{
    DeadlockDetectionTimeout: time.Second(1),
  // ...
}
w := worker.New(c, "your_task_queue_name", workerOptions)
// ...