#dmcache — Public Fediverse posts

I'm running my own #Kubernetes cluster on bare metal at #Hetzner. I'm going through different iterations of node configurations, and trying to figure out how to squeeze the most out of a hardware configuration with a 10TB+ HDD drive and two 512GB #NVME drives. #bcache has apparently been discontinued, which leaves me with #dmcache, which is nicely built into #LVM.

One catch though: you need to create NVME cache volumes for each of the data volumes you create. This is all well and good if you're using a single volume for everything, and tools like #Longhorn work well in this kind of setup. Others, like the #OpenEBS LVM provisioner don't. There is a version in the making that just provisions raw disk images as files on whatever filesystem you have, but it's still lacking some features that are vital to me - primarily the ability to offer up StorageClasses that provision on different paths of the node, so I can pick a fast or slow filesystem to store it on.

Tips for other solutions?

Maximizing hardware with SSD caching via Device Mapper: or, how I got my aging setup's startup time from 8 minutes to mere seconds thanks to Linux.

https://bojidar-bg.dev/blog/2025-02-07-dm-cache/

#linux #archlinux #dmcache #initramfs #performance #devicemapper #ssd

Just switched my root-on-SSD home/var-on-HDD setup over to a single-partition dm-cache setup which automatically caches useful blocks... and it all works!
Hopefully, this will speed up Docker and Firefox going forward. 🥲
...I did feel like a wizard for having to write my own mkinitcpio hook 🎩 - thankfully I had https://wiki.tnonline.net/w/Blog/dm-cache:_Linux_Accelerated_Storage to guide me!

Would anyone be interested in a longer write-up on how I got all that working? 😇
#linux #archlinux #dmcache #initramfs