Only 28G is being used by buff/cache.$free -h              total        used        free      shared  buff/cache   availableMem:           188G         87G         72G         17M         28G         72GSwap:          3.9G          0B        3.9GThis memory isn't being used by processes:$ps -eo size,pid,user,command --sort -size | awk '{ hr=$1/1024 ; printf(%13.2f Mb ,hr) } { for ( x=4 ; x<=NF ; x++ ) { printf(%s ,$x) } print  }' | head         0.00 Mb COMMAND       753.30 Mb /usr/libexec/mysqld --basedir=/usr --datadir=/var/lib/mysql --plugin-dir=/usr/lib64/mysql/plugin --log-error=/var/log/mariadb/mariadb.log --pid-file=/var/run/mariadb/mariadb.pid --socket=/var/lib/mysql/mysql.sock       440.66 Mb /usr/lib/polkit-1/polkitd --no-debug       297.09 Mb /usr/sbin/NetworkManager --no-daemon       297.00 Mb /usr/bin/python -Es /usr/sbin/tuned -l -P       216.72 Mb /usr/sbin/ModemManager       153.12 Mb /usr/sbin/rsyslogd -n       144.51 Mb /usr/libexec/dconf-service        87.64 Mb /usr/bin/python -Es /usr/sbin/firewalld --nofork --nopid        72.33 Mb /sbin/audispd87G used - 28G cache = 59G unaccounted for?Update:According to Gilles, slab allocation is not visible when performing free. After analyzing slabtop and computing the memory allocated for Slab in /proc/meminfo, I've come up with the following totals for memory allocated to the slab:Slab:         46.8651GBThe rest can probably be found throughout /proc/meminfo. Free seems to roll inode and dentry cache into the used category, if I understand this correctly.
Where is my memory being used?
memory