xenium::nikolaev_bounded_queue< T, Policies > Class Template Reference

A bounded lock-free multi-producer/multi-consumer queue. More...

#include <nikolaev_bounded_queue.hpp>

Public Member Functions
	nikolaev_bounded_queue (std::size_t capacity)
	Constructs a new instance with the specified maximum size. More...
bool	try_push (value_type value)
	Tries to push a new element to the queue. More...
bool	try_pop (value_type &result)
	Tries to pop an element from the queue. More...
std::size_t	capacity () const noexcept
	Returns the (rounded) capacity of the queue.

Detailed Description

template<class T, class... Policies>
class xenium::nikolaev_bounded_queue< T, Policies >

A bounded lock-free multi-producer/multi-consumer queue.

This implementation is based on the bounded MPMC queue proposed by Nikolaev [Nik19].

The nikoleav_bounded_queue provides lock-free progress guarantee under the condition that the number of threads concurrently operating on the queue is less than the queue's capacity.

Supported policies:

• xenium::policy::pop_retries
  Defines the number of iterations to spin on a queue entry while waiting for a pending push operation to finish. (optional; defaults to 1000) Note: this policy is applied to the internal queues. The Nikolaev queue internally uses two queues to manage the indexes of free/allocated slots. A push operation pops an item from the free queue, so this policy actually affects both, push and pop operations.

Template Parameters

T
Policies	list of policies to customize the behaviour

Constructor & Destructor Documentation

nikolaev_bounded_queue()

template<class T , class... Policies>

xenium::nikolaev_bounded_queue< T, Policies >::nikolaev_bounded_queue ( std::size_t  capacity )

explicit

Constructs a new instance with the specified maximum size.

Parameters

capacity

max number of elements in the queue; If this is not a power of two, it will be rounded to the next power of two

Member Function Documentation

try_pop()

template<class T , class... Policies>

bool xenium::nikolaev_bounded_queue< T, Policies >::try_pop

(

value_type &

result

)

Tries to pop an element from the queue.

Progress guarantees: lock-free

Parameters

result

Returns

true if the operation was successful, otherwise false

try_push()

template<class T , class... Policies>

bool xenium::nikolaev_bounded_queue< T, Policies >::try_push

(

value_type

value

)

Tries to push a new element to the queue.

Progress guarantees: lock-free

Parameters

value

Returns

true if the operation was successful, otherwise false