Checkpoint write time - anything unusual?

I've just run pgBadger on my pg logs and wonder if those checkpoint
statistics is something I should worry about or not?
The highest write time is about 47 minutes but I'm not sure if that's
checkpoint_completion_target*checkpoint_target value or real time between
sending the command to write and getting response?
If that's the first one - then I assume everything is ok because:
checkpoint_timeout = 8min
checkpoint_completion_target = 0.9

but I'm not sure which value it is...

Hour Written buffers Write time Sync time Total time
00 104,622 2,510.379s 0.558s 2,511.144s
01 23,549 2,218.747s 0.298s 2,219.199s
02 9,776 919.796s 0.244s 920.281s
03 1,075 107.07s 0.398s 107.667s
04 1,062 105.853s 0.396s 106.384s
05 16,216 1,609.462s 0.576s 1,610.245s
06 38,315 2,137.492s 0.246s 2,137.879s
07 51,504 2,571.057s 0.48s 2,571.7s
08 53,921 2,295.652s 2.071s 2,297.957s
09 18,716 1,116.161s 3.132s 1,119.715s
10 9,000 581.912s 3.866s 586.109s
11 12,795 879.337s 2.427s 882.124s
12 13,872 860.987s 1.127s 862.444s
13 14,883 805.011s 0.866s 806.119s
14 13,172 1,062.677s 1.228s 1,064.188s
15 9,375 620.979s 1.013s 622.632s
16 6,268 626.158s 1.059s 627.721s
17 12,387 613.113s 4.849s 618.534s
18 40,641 1,791.432s 1.571s 1,793.546s
19 38,316 1,946.747s 1.343s 1,948.442s
20 69,564 2,817.917s 1.268s 2,819.678s
21 17,333 1,736.004s 0.812s 1,737.25s
22 9,230 924.742s 0.576s 925.49s
23 118,037 2,150.212s 2.167s 2,152.673s

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