Summary
Class that models Mutex Concept using a spin lock, and for processors which support hardware transactional memory (such as Intel® Transactional Synchronization Extensions (Intel® TSX)) may be implemented in a way that allows non-contending changes to the protected data to proceed in parallel.
class speculative_spin_mutex;
#include "tbb/spin_mutex.h"
A speculative_spin_mutex models the Mutex Concept. It is not fair and not recursive. A speculative_spin_mutex is like a spin_mutex, but may provide better throughput than non-speculative mutexes when
Please see the Speculative locking section for more details.
The speculative_spin_mutex is padded to ensure each instance appears on a separate cache line not shared with any other data. Because of that the size of the mutex is twice the cache line size.
For the implementation of speculative_spin_mutex in Intel® Threading Building Blocks (Intel® TBB)) version 4.2 running on a 4th generation Intel® Core™ processor, any lock nesting may thwart speculation.
Depending on the version of Intel TBB and the hardware, other caveats may apply. Please check the Release Notes for more information.
Intel® 64 and IA-32 Architectures Optimization Reference Manual, Order Number 248966-027, June 2013 , Chapter 12.
See Mutex Concept.