cds::backoff Namespace Reference

Different backoff schemes. More...

Data Structures
class	delay
	Delay back-off strategy. More...
struct	delay_const_traits
	Constant traits for delay back-off strategy. More...
struct	delay_runtime_traits
	Runtime traits for delay back-off strategy. More...
struct	empty
	Empty backoff strategy. Do nothing. More...
class	exponential
	Exponential back-off. More...
struct	exponential_const_traits
	backoff::exponential const traits More...
struct	exponential_runtime_traits
	nackoff::exponential runtime traits More...
struct	hint
	Processor hint back-off. More...
struct	pause
	Random pause. More...
struct	yield
	Switch to another thread (yield). Good for thread preemption architecture. More...

Typedefs
template<unsigned int Timeout, class Duration = std::chrono::milliseconds>
using	delay_of = typename make_delay_of< Timeout, Duration >::type
	Delay back-off strategy, template version. More...
typedef exponential< exponential_const_traits >	Default
	Default backoff strategy.
typedef exponential< exponential_const_traits >	LockDefault
	Default back-off strategy for lock primitives.

Detailed Description

Different backoff schemes.

Back-off schema may be used in lock-free algorithms when the algorithm cannot perform some action because a conflict with the other concurrent operation is encountered. In this case current thread can do another work or can call processor's performance hint.

The interface of back-off strategy is following:

struct backoff_strategy {
    void operator()();
    template <typename Predicate> bool operator()( Predicate pr );
    void reset();
};

operator() operator calls back-off strategy's action. It is main part of back-off strategy.

Interruptible back-off template < typename Predicate > bool operator()( Predicate pr ) allows to interrupt back-off spinning if pr predicate returns true. Predicate is a functor with the following interface:

struct predicate {
    bool operator()();
};

reset() function resets internal state of back-off strategy to initial state. It is required for some back-off strategies, for example, exponential back-off.

Typedef Documentation

delay_of

template<unsigned int Timeout, class Duration = std::chrono::milliseconds>

using cds::backoff::delay_of = typedef typename make_delay_of< Timeout, Duration >::type

Delay back-off strategy, template version.

This is a simplified version of backoff::delay class. Template parameter Timeout sets a delay timeout of Duration unit.