Effect of lock free QSBR step 4

baseline commit, patch

• parallel_get/1/70000: 44% speedup
• parallel_get/2/70000: 78% speedup
• parallel_get/4/70000: 72% speedup
• parallel_get/8/70000: 63% speedup
• parallel_get/16/70000: 72% speedup
• parallel_get/1/2000000: 37% speedup
• parallel_get/2/2000000: 70% speedup
• parallel_get/4/2000000: 66% speedup
• parallel_get/8/2000000: 80% speedup
• parallel_get/16/2000000: 78% speedup
• parallel_insert_disjoint_ranges/1/70000: 17% speedup
• parallel_insert_disjoint_ranges/2/70000: 8% speedup
• parallel_insert_disjoint_ranges/4/70000: 50% speedup
• parallel_insert_disjoint_ranges/8/70000: 48% speedup
• parallel_insert_disjoint_ranges/16/70000: 72% speedup
• parallel_insert_disjoint_ranges/32/70000: 86% speedup
• parallel_insert_disjoint_ranges/1/2000000: 28% speedup
• parallel_insert_disjoint_ranges/2/2000000: -
• parallel_insert_disjoint_ranges/4/2000000: 38% speedup
• parallel_insert_disjoint_ranges/8/2000000: 47% speedup
• parallel_insert_disjoint_ranges/16/2000000: 59% speedup
• parallel_insert_disjoint_ranges/32/2000000: 65% speedup
• parallel_delete_disjoint_ranges/1/70000: 32% speedup
• parallel_delete_disjoint_ranges/2/70000: 49% speedup
• parallel_delete_disjoint_ranges/4/70000: 65% speedup
• parallel_delete_disjoint_ranges/8/70000: 63% speedup
• parallel_delete_disjoint_ranges/16/70000: 96% speedup
• parallel_delete_disjoint_ranges/32/70000: 99% speedup
• parallel_delete_disjoint_ranges/1/2000000: -
• parallel_delete_disjoint_ranges/2/2000000: 49% speedup
• parallel_delete_disjoint_ranges/4/2000000: 67% speedup
• parallel_delete_disjoint_ranges/8/2000000: 76% speedup
• parallel_delete_disjoint_ranges/16/2000000: 93% speedup
• parallel_delete_disjoint_ranges/32/2000000: 89% speedup