Postgres 15.3, IO-bound, per-client time to finish the l.i1 benchmark step

gistfile1.txt

a
21508.5
23096.1
27242.3
30292.4
31352.5
34355.2
34918.1
40381.9

a1
26528.3
27421.4
32993.5
34536.7
39219.5
43579.0
45807.4
50975.7

a3
20095.1
22029.0
22219.2
31727.1
42884.6
43558.6
44827.9
45205.8

a4
21156.2
23119.2
23985.1
24167.2
24967.0
27227.4
28530.8
35151.9

a7
22831.8
23482.0
24267.8
26453.5
27802.0
30560.8
36494.5
41520.5

a10
22963.0
28186.3
28946.0
31725.8
38312.5
39500.2
42225.0
44959.0

a12
21491.5
22577.6
24747.8
28904.0
30749.9
31693.9
34174.5
34755.1

a15
7907.9
14313.4
14739.7
14782.8
16145.2
23601.0
30213.0
33010.0

a16
9317.3
10919.9
15838.9
17151.2
19089.2
20842.7
22283.3
22545.8

a23
15662.9
15852.9
17109.1
21597.7
22531.6
23043.1
23454.5
26703.0

a24
29897.1
30773.9
31511.7
31544.7
32069.1
32215.4
32489.7
35360.7

a25
11874.9
18372.4
19880.9
21391.4
26259.4
30855.8
34077.6
35686.3

a26
17934.0
21416.5
22353.4
22501.5
23735.8
25709.8
26825.9
27682.9

a27
9758.2
16842.2
19758.9
20889.0
25073.2
25458.7
27437.8
28000.3

a28
15038.1
15690.7
19743.0
25990.5
27437.6
27931.2
29667.0
30505.9