Slow HDD read.

[lelik107]

Hello guys, BLAKE3 Team! I found out that any b3sum_windows_x64_bin.exe reads a HDD slow. What exactly I did:
I calculated the sums of Windows 10 iso images, 5.3 Gb and 5.8 Gb files, WD RE 1 Tb was used, I measured with a simple stopwatch.The speed of this HDD is 140-80 Mbyte/s. And it's not about a disk cache, because I rebooted after every test.
So v1.5.1, v1.3.3 ~ 5.3 Gb - 1 m 45 s, 5.8 Gb ~ 1 m 57 s; v1.0.0 a bit faster ~ 5.3 Gb - 1 m 22 s, 5.8 Gb ~ 1 m 31 s.
And I hear the disk spinning.
b2sum-bin_20130305.zip, 7-zip h command with any algo ~ 5.3 Gb - 45-48 s, 5.8 Gb ~ 55 s -1 m;.
And I don't hear the disk spinning.
So my simple question is: why b3sum is this slower?