SHMEM_LOCKS: MCS implementation of SHMEM LOCKS #12003
                
     Merged
            
            
          
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Adding MCS algorithm-based implementation for shmem_locks to improve performance for large scale SHMEM applications using locks. MCS lock is now the default algorithm, use the following MCA parameter to disable. --mca oshmem_enable_mcs_lock 0 to disable mcs locks and revert to default ticket locking. --mca oshmem_api_verbose 10 for debug information on shmem_locks.
@brminich @manjugv @yosefe