moved to bcache

1TB  SSD cache
10TB HDD backing

https://www.reddit.com/r/linux_gaming/comments/tc3rkj/set_up_bcache_to_speed_up_game_loading_with_an/
https://wiki.archlinux.org/title/Bcache

[freestation ~]# cat /etc/tmpfiles.d/bcache.conf 
w /sys/block/bcache0/bcache/sequential_cutoff                    			- - - - 0
w /sys/block/bcache0/queue/read_ahead_kb                         			- - - - 16348
w /sys/fs/bcache/df672546-63cf-499f-b4be-b568ecab7f76/congested_read_threshold_us	- - - - 0
w /sys/fs/bcache/df672546-63cf-499f-b4be-b568ecab7f76/congested_write_threshold_us	- - - - 0
[freestation ~]# 

[freestation ~]# mount | grep bcache
/dev/bcache0 on /var/lib/freestation type btrfs (rw,relatime,ssd,discard,space_cache=v2,subvolid=257,subvol=/@freestation)
/dev/bcache0 on /var/lib/flatpak type btrfs (rw,relatime,ssd,discard,space_cache=v2,subvolid=256,subvol=/@flatpak)
/dev/bcache0 on /home type btrfs (rw,relatime,ssd,discard,space_cache=v2,subvolid=258,subvol=/@home)
[freestation ~]# 

[freestation ~]# bcache-super-show /dev/sdb
sb.magic		ok
sb.first_sector		8 [match]
sb.csum			AE5CE06EBF6E8D70 [match]
sb.version		3 [cache device]

dev.label		(empty)
dev.uuid		c90ee735-8692-4275-b5ea-454705771de7
dev.sectors_per_block	1
dev.sectors_per_bucket	1024
dev.cache.first_sector	1024
dev.cache.cache_sectors	1953523712
dev.cache.total_sectors	1953524736
dev.cache.ordered	yes
dev.cache.discard	no
dev.cache.pos		0
dev.cache.replacement	0 [lru]

cset.uuid		df672546-63cf-499f-b4be-b568ecab7f76
[freestation ~]# bcache-super-show /dev/sdc
sb.magic		ok
sb.first_sector		8 [match]
sb.csum			A40BFC42946F536A [match]
sb.version		1 [backing device]

dev.label		(empty)
dev.uuid		5bb06a50-16bb-4837-a449-10a3d4599c31
dev.sectors_per_block	1
dev.sectors_per_bucket	1024
dev.data.first_sector	16
dev.data.cache_mode	2 [writearound]
dev.data.cache_state	1 [clean]

cset.uuid		df672546-63cf-499f-b4be-b568ecab7f76
[freestation ~]#