zram, formerly called compcache, is a Linux kernel module for creating a compressed block device in RAM, i.e. a RAM disk with on-the-fly disk compression. The block device created with zram can then be used for swap or as a general-purpose RAM disk. The two most common uses for zram are for the storage of temporary files (/tmp) and as a swap device.
I have a mini PC that has been barreling through NVMe disks but Alpine Linux’ “usb” install mode just wasn’t great either. So I use a “sys” (traditional install) on an NVMe disk but have directories like /var/log, /tmp, etc. on Zstandard compressed zram disks. It’s been pretty fantastic honestly.
It’s a Linux feature to compress some of your memory and then store it in a RAM disk. For systems with limited memory, it makes it go further.
https://en.wikipedia.org/wiki/Zram
I have a mini PC that has been barreling through NVMe disks but Alpine Linux’ “usb” install mode just wasn’t great either. So I use a “sys” (traditional install) on an NVMe disk but have directories like
/var/log,/tmp, etc. on Zstandard compressed zram disks. It’s been pretty fantastic honestly.