notebook ~ # sync ; echo 3> /proc/sys/vm/drop_caches

notebook ~ # zramctl
NAME       ALGORITHM DISKSIZE DATA COMPR TOTAL STREAMS MOUNTPOINT
/dev/zram0 lz4             1G   4K   64B    4K       1 [SWAP]

notebook ~ # swapon -s
Filename                                Type            Size    Used    Priority
/dev/sda1                               partition       4194300 0       -1
/dev/zram0                              partition       1048572 0       16383

notebook ~ # free -m
              total        used        free      shared  buff/cache   available
Mem:           1871          39        1518           1         312        1800
Swap:          5119           0        5119