Hello, I was trying to test zstd compression for zram devices with kernel 4.15
But to my surprize I found zstd comressor missing from list of compression
I found out this patch or equivalent was still missing in 4.15 and missing in
4.16 as it nearing -rc1:
[PATCH v4 5/5] crypto: Add zstd support
After manually applying this patch I can see
[lzo] lz4 lz4hc 842 zstd
and can change algo to zstd
If I try and mkfs.ext2 this device (with size, say, ~1Gb) - I can uncompress
nearly full kernel tree into it (I first run out of inodes, tons of small files
for such small "disk", re-run mkfs with specified number of inodes, around 100
000, worked). But 1Gb device probably was visible size of device, not amount of
memory it consumes..So, I run mkfs.btrfs over /dev/zram0 with zstd compression.
This give me ~1Gb sized device able to keep full kernel tree, and compile it ,
too. So, I assume it worked ....