effective_io_concurrency=0
                                                                      QUERY PLAN                                                                      
------------------------------------------------------------------------------------------------------------------------------------------------------
 Bitmap Heap Scan on pgbench_accounts  (cost=137192.84..1960989.89 rows=1 width=97) (actual time=40261.322..40261.322 rows=0 loops=1)
   Recheck Cond: ((aid >= 1000) AND (aid <= 10000000))
   Rows Removed by Index Recheck: 23
   Filter: (abalance <> 0)
   Rows Removed by Filter: 9999001
   Heap Blocks: exact=97869 lossy=66050
   Buffers: shared hit=3 read=191240
   ->  Bitmap Index Scan on pgbench_accounts_pkey  (cost=0.00..137192.84 rows=10540117 width=0) (actual time=3366.623..3366.623 rows=9999001 loops=1)
         Index Cond: ((aid >= 1000) AND (aid <= 10000000))
         Buffers: shared hit=3 read=27321
 Planning time: 17.285 ms
 Execution time: 40262.781 ms
(12 rows)

effective_io_concurrency=1
                                                                      QUERY PLAN                                                                      
------------------------------------------------------------------------------------------------------------------------------------------------------
 Bitmap Heap Scan on pgbench_accounts  (cost=137192.84..1960989.89 rows=1 width=97) (actual time=98124.607..98124.607 rows=0 loops=1)
   Recheck Cond: ((aid >= 1000) AND (aid <= 10000000))
   Rows Removed by Index Recheck: 23
   Filter: (abalance <> 0)
   Rows Removed by Filter: 9999001
   Heap Blocks: exact=97869 lossy=66050
   Buffers: shared hit=3 read=191240
   ->  Bitmap Index Scan on pgbench_accounts_pkey  (cost=0.00..137192.84 rows=10540117 width=0) (actual time=3373.380..3373.380 rows=9999001 loops=1)
         Index Cond: ((aid >= 1000) AND (aid <= 10000000))
         Buffers: shared hit=3 read=27321
 Planning time: 18.110 ms
 Execution time: 98125.987 ms
(12 rows)

effective_io_concurrency=2
                                                                      QUERY PLAN                                                                      
------------------------------------------------------------------------------------------------------------------------------------------------------
 Bitmap Heap Scan on pgbench_accounts  (cost=137192.84..1960989.89 rows=1 width=97) (actual time=55340.663..55340.663 rows=0 loops=1)
   Recheck Cond: ((aid >= 1000) AND (aid <= 10000000))
   Rows Removed by Index Recheck: 23
   Filter: (abalance <> 0)
   Rows Removed by Filter: 9999001
   Heap Blocks: exact=97869 lossy=66050
   Buffers: shared hit=3 read=191240
   ->  Bitmap Index Scan on pgbench_accounts_pkey  (cost=0.00..137192.84 rows=10540117 width=0) (actual time=3306.896..3306.896 rows=9999001 loops=1)
         Index Cond: ((aid >= 1000) AND (aid <= 10000000))
         Buffers: shared hit=3 read=27321
 Planning time: 30.986 ms
 Execution time: 55343.776 ms
(12 rows)

effective_io_concurrency=4
                                                                      QUERY PLAN                                                                      
------------------------------------------------------------------------------------------------------------------------------------------------------
 Bitmap Heap Scan on pgbench_accounts  (cost=137192.84..1960989.89 rows=1 width=97) (actual time=52504.298..52504.298 rows=0 loops=1)
   Recheck Cond: ((aid >= 1000) AND (aid <= 10000000))
   Rows Removed by Index Recheck: 23
   Filter: (abalance <> 0)
   Rows Removed by Filter: 9999001
   Heap Blocks: exact=97869 lossy=66050
   Buffers: shared hit=3 read=191240
   ->  Bitmap Index Scan on pgbench_accounts_pkey  (cost=0.00..137192.84 rows=10540117 width=0) (actual time=3332.724..3332.724 rows=9999001 loops=1)
         Index Cond: ((aid >= 1000) AND (aid <= 10000000))
         Buffers: shared hit=3 read=27321
 Planning time: 17.100 ms
 Execution time: 52505.638 ms
(12 rows)

effective_io_concurrency=8
                                                                      QUERY PLAN                                                                      
------------------------------------------------------------------------------------------------------------------------------------------------------
 Bitmap Heap Scan on pgbench_accounts  (cost=137192.84..1960989.89 rows=1 width=97) (actual time=54952.558..54952.558 rows=0 loops=1)
   Recheck Cond: ((aid >= 1000) AND (aid <= 10000000))
   Rows Removed by Index Recheck: 23
   Filter: (abalance <> 0)
   Rows Removed by Filter: 9999001
   Heap Blocks: exact=97869 lossy=66050
   Buffers: shared hit=3 read=191240
   ->  Bitmap Index Scan on pgbench_accounts_pkey  (cost=0.00..137192.84 rows=10540117 width=0) (actual time=3390.833..3390.833 rows=9999001 loops=1)
         Index Cond: ((aid >= 1000) AND (aid <= 10000000))
         Buffers: shared hit=3 read=27321
 Planning time: 18.043 ms
 Execution time: 54954.024 ms
(12 rows)

effective_io_concurrency=16
                                                                      QUERY PLAN                                                                      
------------------------------------------------------------------------------------------------------------------------------------------------------
 Bitmap Heap Scan on pgbench_accounts  (cost=137192.84..1960989.89 rows=1 width=97) (actual time=54345.036..54345.036 rows=0 loops=1)
   Recheck Cond: ((aid >= 1000) AND (aid <= 10000000))
   Rows Removed by Index Recheck: 23
   Filter: (abalance <> 0)
   Rows Removed by Filter: 9999001
   Heap Blocks: exact=97869 lossy=66050
   Buffers: shared hit=3 read=191240
   ->  Bitmap Index Scan on pgbench_accounts_pkey  (cost=0.00..137192.84 rows=10540117 width=0) (actual time=3401.819..3401.819 rows=9999001 loops=1)
         Index Cond: ((aid >= 1000) AND (aid <= 10000000))
         Buffers: shared hit=3 read=27321
 Planning time: 17.164 ms
 Execution time: 54346.455 ms
(12 rows)

effective_io_concurrency=32
                                                                      QUERY PLAN                                                                      
------------------------------------------------------------------------------------------------------------------------------------------------------
 Bitmap Heap Scan on pgbench_accounts  (cost=137192.84..1960989.89 rows=1 width=97) (actual time=55195.211..55195.211 rows=0 loops=1)
   Recheck Cond: ((aid >= 1000) AND (aid <= 10000000))
   Rows Removed by Index Recheck: 23
   Filter: (abalance <> 0)
   Rows Removed by Filter: 9999001
   Heap Blocks: exact=97869 lossy=66050
   Buffers: shared hit=3 read=191240
   ->  Bitmap Index Scan on pgbench_accounts_pkey  (cost=0.00..137192.84 rows=10540117 width=0) (actual time=3373.154..3373.154 rows=9999001 loops=1)
         Index Cond: ((aid >= 1000) AND (aid <= 10000000))
         Buffers: shared hit=3 read=27321
 Planning time: 18.490 ms
 Execution time: 55196.626 ms
(12 rows)

effective_io_concurrency=64
                                                                      QUERY PLAN                                                                      
------------------------------------------------------------------------------------------------------------------------------------------------------
 Bitmap Heap Scan on pgbench_accounts  (cost=137192.84..1960989.89 rows=1 width=97) (actual time=55056.559..55056.559 rows=0 loops=1)
   Recheck Cond: ((aid >= 1000) AND (aid <= 10000000))
   Rows Removed by Index Recheck: 23
   Filter: (abalance <> 0)
   Rows Removed by Filter: 9999001
   Heap Blocks: exact=97869 lossy=66050
   Buffers: shared hit=3 read=191240
   ->  Bitmap Index Scan on pgbench_accounts_pkey  (cost=0.00..137192.84 rows=10540117 width=0) (actual time=3351.440..3351.440 rows=9999001 loops=1)
         Index Cond: ((aid >= 1000) AND (aid <= 10000000))
         Buffers: shared hit=3 read=27321
 Planning time: 17.142 ms
 Execution time: 55057.956 ms
(12 rows)

effective_io_concurrency=128
                                                                      QUERY PLAN                                                                      
------------------------------------------------------------------------------------------------------------------------------------------------------
 Bitmap Heap Scan on pgbench_accounts  (cost=137192.84..1960989.89 rows=1 width=97) (actual time=54962.081..54962.081 rows=0 loops=1)
   Recheck Cond: ((aid >= 1000) AND (aid <= 10000000))
   Rows Removed by Index Recheck: 23
   Filter: (abalance <> 0)
   Rows Removed by Filter: 9999001
   Heap Blocks: exact=97869 lossy=66050
   Buffers: shared hit=3 read=191240
   ->  Bitmap Index Scan on pgbench_accounts_pkey  (cost=0.00..137192.84 rows=10540117 width=0) (actual time=3410.678..3410.678 rows=9999001 loops=1)
         Index Cond: ((aid >= 1000) AND (aid <= 10000000))
         Buffers: shared hit=3 read=27321
 Planning time: 17.441 ms
 Execution time: 54963.510 ms
(12 rows)

effective_io_concurrency=256
                                                                      QUERY PLAN                                                                      
------------------------------------------------------------------------------------------------------------------------------------------------------
 Bitmap Heap Scan on pgbench_accounts  (cost=137192.84..1960989.89 rows=1 width=97) (actual time=54337.825..54337.825 rows=0 loops=1)
   Recheck Cond: ((aid >= 1000) AND (aid <= 10000000))
   Rows Removed by Index Recheck: 23
   Filter: (abalance <> 0)
   Rows Removed by Filter: 9999001
   Heap Blocks: exact=97869 lossy=66050
   Buffers: shared hit=3 read=191240
   ->  Bitmap Index Scan on pgbench_accounts_pkey  (cost=0.00..137192.84 rows=10540117 width=0) (actual time=3380.008..3380.008 rows=9999001 loops=1)
         Index Cond: ((aid >= 1000) AND (aid <= 10000000))
         Buffers: shared hit=3 read=27321
 Planning time: 16.987 ms
 Execution time: 54339.258 ms
(12 rows)