folly::VirtualExecutor

Synopsis

Declared in <folly/executors/VirtualExecutor.h>

class VirtualExecutor
    : public DefaultKeepAliveExecutor

Description

Multiple VirtualExecutors can be backed by a single Executor.

VirtualExecutor's destructor blocks until all tasks scheduled through it are complete. Executor's destructor also blocks until all VirtualExecutors backed by it are released.

Base Classes

Name	Description
`DefaultKeepAliveExecutor`	An Executor accepts units of work with add(), which should be threadsafe.

Types

Name	Description
`WeakRefExecutor`	Marker base for the weak-reference executor wrappers.

Type Aliases

Name	Description
`KeepAlive`	Alias for ExecutorKeepAlive, a safe pointer to an Executor.

Member Functions

Name	Description
`VirtualExecutor` [constructor]	Constructors
`~VirtualExecutor` [destructor] [virtual]	Destroys the executor, blocking until all scheduled tasks complete.
`operator=` [deleted]	Copy assignment operator (deleted).
`add`	`add` overloads
`addWithPriority`	`addWithPriority` overloads
`getNumPriorities` [virtual]	Returns the number of priority levels supported by the backing executor.
`weakRef`	Returns a weak keep-alive to this executor.

Static Member Functions

Name	Description
`getKeepAliveToken`	`getKeepAliveToken` overloads
`getWeakRef`	Returns a weak keep-alive to `executor` that does not extend its lifetime.
`invokeCatchingExns`	Invokes `f`, logging and swallowing any exception it throws.

Static Data Members

Name	Description
`HI_PRI`	Highest schedulable priority.
`LO_PRI`	Lowest schedulable priority.
`MID_PRI`	Medium (default) schedulable priority.

Protected Member Functions

Name	Description
`joinAndResetKeepAlive`	Joins the keep-alive, then reinstates a fresh one so the executor is reusable.
`joinKeepAlive`	Releases this executor's own keep-alive and waits for all others to drain.
`keepAliveAcquire` [virtual]	Acquire a keep alive token. Should return false if keep-alive mechanism is not supported.
`keepAliveRelease` [virtual]	Release a keep alive token previously acquired by keepAliveAcquire(). Will never be called if keepAliveAcquire() returns false.

Protected Static Member Functions

Name	Description
`isKeepAliveDummy`	Returns true if the KeepAlive is constructed from an executor that does not support the keep alive ref-counting functionality
`keepAliveAcquire`	Acquires a keep-alive reference on `executor`.
`keepAliveRelease`	Releases a keep-alive reference on `executor`.
`makeKeepAlive`	Makes a counted (non-dummy, non-alias) keep-alive referring to `executor`.

Non-Member Functions

Name	Description
`async_tracing::logFutureVia`	Trace hook invoked when a Future is rescheduled onto an executor.
`async_tracing::logGetGlobalCPUExecutor`	Trace hook invoked when the global CPU executor is retrieved.
`async_tracing::logGetImmutableCPUExecutor`	Trace hook invoked when the immutable CPU executor is retrieved.
`async_tracing::logSemiFutureVia`	Trace hook invoked when a SemiFuture is rescheduled onto an executor.
`async_tracing::logSetGlobalCPUExecutor`	Trace hook invoked when the global CPU executor is set.