vmtouch shows cache size very large than free

[Homio]

Hi,
I use vmtouch to detect /usr/bin, It showed very large cache, but the free command did not have much.

./vmtouch /usr/bin/
vmtouch: WARNING: not following symbolic link /usr/bin/foo2zjs-icc2ps
vmtouch: WARNING: not following symbolic link /usr/bin/llvm-ranlib-12
......
vmtouch: WARNING: not following symbolic link /usr/sbin/cpgr
vmtouch: WARNING: not following symbolic link /usr/sbin/e2mmpstatus
Files: 251653
Directories: 27437
Resident Pages: 7480156/7508645 28G/28G 99.6%
Elapsed: 2.5245 seconds

free -m
total used free shared buff/cache available
Mem: 31735 6411 14665 97 10658 24779
Swap: 2047 1469 578