Template Class DataShuttle

• Defined in File data_shuttle.h

Class Documentation

template<typename Job, typename Result>
class DataShuttle

Encapsulates the full life cycle of DataLoader jobs.

When a new job is enqueued to the DataShuttle, a counter for in-flight jobs is bumped. This job is said to be “in-flight” until its result is popped. Worker threads dequeue jobs as soon as they are available. When a worker finishes a job, it enqueues the result. Only when the main thread dequeues a result is the count of in-flight jobs decremented. When the main thread attempts to dequeue a job but no jobs are in-flight, that means the epoch is complete and pop_result returns an empty optional.

Public Functions

inline void push_job(Job job)

Pushes a new job. Called by the main thread.

inline void push_result(Result result)

Pushes the result of a job. Called by worker threads.

inline Job pop_job()

Returns the next job, blocking until there is one available.

Called by worker threads.

inline std::optional<Result> pop_result(std::optional<std::chrono::milliseconds> timeout = std::nullopt)

Returns the result of a job, or nullopt if all jobs were exhausted.

Called by the main thread.

inline void drain()

Discards any jobs that are not yet in flight, and waits for all in-flight jobs to finish, discarding their result.

inline size_t in_flight_jobs() const noexcept

Returns the number of jobs that are still in progress.

When this number is zero, an epoch is finished.