# Workgroups Schedule one or more threads to run at regular intervals and before specific deadlines. ## Discussion A workgroup manages one or more threads that work cooperatively toward a common goal. Use workgroups to coordinate the efforts of threads that handle real-time audio work. Registering threads with a workgroup helps the system direct work to the right system resources, and also helps it manage the competing needs of low-power consumption with maximum rendering output. ## Topics ### Essentials ### Interval Tasks [`os_workgroup_interval_start`](/documentation/os/os_workgroup_interval_start) Starts the regular execution of the workgroup’s threads at the specified time. [`os_workgroup_interval_update`](/documentation/os/os_workgroup_interval_update) Schedules a new deadline for workgroup threads that run at regular intervals. [`os_workgroup_interval_finish`](/documentation/os/os_workgroup_interval_finish) Stops the current interval-based execution of the workgroup’s threads. [`os_workgroup_interval_t`](/documentation/os/os_workgroup_interval_t) A workgroup object that supports the scheduling of threads on a repeating cadence. [`os_workgroup_interval_data_t`](/documentation/os/os_workgroup_interval_data_t) An opaque structure that contains additional configuration data for the interval workgroup. [`os_clockid_t`](/documentation/os/os_clockid_t) Options for how to specify time-specific values in an interval workgroup. ### Parallel [`os_workgroup_parallel_create`](/documentation/os/os_workgroup_parallel_create) Creates a new workgroup that manges threads working on a single task in parallel. [`os_workgroup_parallel_t`](/documentation/os/os_workgroup_parallel_t) A workgroup object that supports the scheduling of threads that work in parallel to complete a task. ### Thread Attachment [`os_workgroup_join`](/documentation/os/os_workgroup_join) Adds the current thread to the specified workgroup. [`os_workgroup_leave`](/documentation/os/os_workgroup_leave) Removes the current thread from the workgroup it previously joined. [`os_workgroup_join_token_t`](/documentation/os/os_workgroup_join_token_t) An opaque token that represents a connection between a thread and a workgroup. ### Cancellation [`os_workgroup_cancel`](/documentation/os/os_workgroup_cancel) Cancels and invalidates the specified workgroup. [`os_workgroup_testcancel`](/documentation/os/os_workgroup_testcancel) Returns a Boolean value that indicates whether the workgroup is canceled. ### Workgroup Configuration [`os_workgroup_max_parallel_threads`](/documentation/os/os_workgroup_max_parallel_threads) Returns the maximum number of threads that the system recommends you add to the specified workgroup. [`os_workgroup_mpt_attr_t`](/documentation/os/os_workgroup_mpt_attr_t) An opaque structure containing attributes related to a request for the maximum number of parallel threads. [`os_workgroup_set_working_arena`](/documentation/os/os_workgroup_set_working_arena) Distributes a block of managed memory to the threads of a workgroup. [`os_workgroup_get_working_arena`](/documentation/os/os_workgroup_get_working_arena) Retrieves the workgroup’s shared data, and the thread-specific index into that data. [`os_workgroup_index`](/documentation/os/os_workgroup_index) A unique index that the workgroup assigns to its joined threads. [`os_workgroup_working_arena_destructor_t`](/documentation/os/os_workgroup_working_arena_destructor_t) A function that deallocates a workgroup’s currently assigned shared memory. ### Common Utilities [`os_workgroup_create_with_workgroup`](/documentation/os/os_workgroup_create_with_workgroup) Create a new workgroup that is bound to the specified workgroup. [`os_workgroup_create_with_port`](/documentation/os/os_workgroup_create_with_port) Creates a new workgroup that is bound to the workgroup with the specified Mach port. [`os_workgroup_copy_port`](/documentation/os/os_workgroup_copy_port) Returns the Mach port associated with the workgroup. [`os_workgroup_t`](/documentation/os/os_workgroup_t) An opaque object representing a default workgroup in the current process. [`os_workgroup_attr_t`](/documentation/os/os_workgroup_attr_t) An opaque structure for storing workgroup-related attributes. ### Objective-C Support [`OS_os_workgroup_interval`](/documentation/os/OS_os_workgroup_interval-c.class) [`OS_os_workgroup_interval`](/documentation/os/OS_os_workgroup_interval-c.protocol) [`OS_os_workgroup`](/documentation/os/OS_os_workgroup) [`OS_object`](/documentation/os/OS_object) ### Internal Structures [`OS_os_workgroup_parallel`](/documentation/os/OS_os_workgroup_parallel-c.class) [`OS_os_workgroup_parallel`](/documentation/os/OS_os_workgroup_parallel-c.protocol) --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)