Something is wrong with those v2.2.7 & v2.2.8 versions,
they are causing high constant CPU usage 13%-17%
switching back to v2.2.6 CPU usage drops to 3%-4%
you forgot to tell which algorithm are you talking about, which gpu's, and windows or linux?
algorithm: 'sha512_256d_radiant'
os: windows (10 & 11, issue exist on both )
GPUs: Any GPUs models like => [3080, 3070, 3070 Ti, 3090, 3060, RX5600XT, 2070, 2070M, 1660M, 1080 Ti, 1070 Ti, 1070, 1060 6GB, 1050 Ti]
system: Any PCs => [Intel/AMD], [desktop/notebook]
Some more examples from 4 different PCs:
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pc1:
v2.2.
6 CPU:

v2.2.
8 CPU:

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pc2:
v2.2.
6 CPU:

v2.2.
8 CPU:

------------------------------------------------------------------------------------
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pc3:
v2.2.
6 CPU:

v2.2.
8 CPU:

------------------------------------------------------------------------------------
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pc4:
v2.2.
6 CPU:

v2.2.
8 CPU:

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