seastar::alien Namespace Reference

Detailed Description

Integration with non-seastar applications.

Classes
class	message_queue
class	instance

Functions
template<typename Func >
void	run_on (instance &instance, unsigned shard, Func func)
template<typename Func >
void	run_on (unsigned shard, Func func)
template<typename Func , typename T = internal::return_type_t<Func>>
std::future< T >	submit_to (instance &instance, unsigned shard, Func func)
template<typename Func , typename T = internal::return_type_t<Func>>
std::future< T >	submit_to (unsigned shard, Func func)

Function Documentation

run_on() [1/2]

template<typename Func >

void seastar::alien::run_on	(	instance &	instance,
		unsigned	shard,
		Func	func
	)

Runs a function on a remote shard from an alien thread where engine() is not available.

Parameters

instance	designates the Seastar instance to process the message
shard	designates the shard to run the function on
func	a callable to run on shard t. If func is a temporary object, its lifetime will be extended by moving it. If func is a reference, the caller must guarantee that it will survive the call.

Note

the func must not throw and should return void. as we cannot identify the alien thread, hence we are not able to post the fulfilled promise to the message queue managed by the shard executing the alien thread which is interested to the return value. Please use submit_to() instead, if func throws.

run_on() [2/2]

template<typename Func >

void seastar::alien::run_on	(	unsigned	shard,
		Func	func
	)

Runs a function on a remote shard from an alien thread where engine() is not available.

Parameters

shard	designates the shard to run the function on
func	a callable to run on shard t. If func is a temporary object, its lifetime will be extended by moving it. If func is a reference, the caller must guarantee that it will survive the call.

Note

the func must not throw and should return void. as we cannot identify the alien thread, hence we are not able to post the fulfilled promise to the message queue managed by the shard executing the alien thread which is interested to the return value. Please use submit_to() instead, if func throws.

submit_to() [1/2]

template<typename Func , typename T = internal::return_type_t<Func>>

std::future<T> seastar::alien::submit_to	(	instance &	instance,
		unsigned	shard,
		Func	func
	)

Runs a function on a remote shard from an alien thread where engine() is not available.

Parameters

instance	designates the Seastar instance to process the message
shard	designates the shard to run the function on
func	a callable to run on shard. If func is a temporary object, its lifetime will be extended by moving it. If func is a reference, the caller must guarantee that it will survive the call.

Returns

whatever func returns, as a std::future<>

Note

the caller must keep the returned future alive until func returns

submit_to() [2/2]

template<typename Func , typename T = internal::return_type_t<Func>>

std::future<T> seastar::alien::submit_to	(	unsigned	shard,
		Func	func
	)

Runs a function on a remote shard from an alien thread where engine() is not available.

Parameters

shard	designates the shard to run the function on
func	a callable to run on shard. If func is a temporary object, its lifetime will be extended by moving it. If func is a reference, the caller must guarantee that it will survive the call.

Returns

whatever func returns, as a std::future<>

Note

the caller must keep the returned future alive until func returns