That depends of your physical memory also of the Operating system. By the whay don't use k above 4096 without SET the N value, any value 4096 without the correct N will lead on a sub-optimal behavior just like your example
That is on the documentation:
https://github.com/albertobsd/keyhunt?tab=readme-ov-file#what-values-use-according-to-my-current-ram2 G -k 128
4 G -k 256
8 GB -k 512
16 GB -k 1024
32 GB -k 2048
64 GB -n 0x100000000000 -k 4096
128 GB -n 0x400000000000 -k 4096
256 GB -n 0x400000000000 -k 8192
512 GB -n 0x1000000000000 -k 8192
1 TB -n 0x1000000000000 -k 16384
2 TB -n 0x4000000000000 -k 16384
4 TB -n 0x4000000000000 -k 32768
8 TB -n 0x10000000000000 -k 32768