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→Mutual Exclusion
C++ 11 threads and language native threads unfortunately lack this luxury. In order to parallelize a loop using std Threads, it is the programmers responsibility to calculate the range of each iteration within the loop the be parallelized. This is usually done using SPMD techniques.
====Mutual ExclusionSynchronization==== C++ 11 and Openmp are designed to avoid race conditions and share data between threads in various ways. ===Shared Memory===
=====OpenMp=====
Openmp uses the shared clause to define what variables are shared among all threads. All threads within a team access the same storage area for shared variables.
The he shared clause would be located within a pragma statement. The clause is defined as follows.
shared(var)
=====C++ 11=====
The atomic class provides an atomic object type which can eliminate the possibility of data races by providing synchronization between threads.
Accesses to atomic objects may establish inter-thread synchronization and order non-atomic memory accesses.
<br>
Atomic types are defined as
std::atomic<type> var_name;
===Mutual Exclusion===
=====OpenMp=====
Openmp Handles Mutual Exclusion by
=====C++ 11=====
• try_lock - tries to lock the mutex, returns if the mutex is not available
====Implementations====