Arch Linux

EmHCtH

Member

Registered: 2014-07-18

Posts: 1

Configuration with RAID0

Hello. I am just looking for feedback on my setup. Not looking for howto. I can figure that out for myself.

My PC has 256g SSD and 2x 500g HDD. My thought was to raid0 (mdadm) the hdds and use for /home and swap while sdd is for the rest. I have an external nas I can use for backing up, so not worried about data safety. Just speed. I am the only user.  How dumb is this?

Note: I am returning to Arch after a bit of a break. System is currently win10 and I will be removing it all. Already saved important data. Most what I have found is either old or someone trying to raid SDDs which I have learned does not have much benefits. But my understanding is using hdds should.

Lone_Wolf

Administrator

From: Netherlands, Europe

Registered: 2005-10-04

Posts: 13,564

Re: Configuration with RAID0

many parts of /home (especially dotfiles) benefit a lot from ssd speed .
I suggest to use the raid for storing large things like movies , git tree clones etc.

swap benefits from ssd speed, but it also needs room .
You could have a smallish swap on the ssd and larger ones on the raid to combine speed and size .

(Most of the time my swap use is between 0 and 4 Gib, but I had to allocate 24 Gib to prevent oom issues from crashing my gui during some tasks)

---

Disliking systemd intensely, but not satisfied with alternatives so focusing on taming systemd.

clean chroot building not flexible enough ?
Try clean chroot manager by graysky

ozwigh

Member

Registered: 2014-10-07

Posts: 27

Re: Configuration with RAID0

I'd suggest leaving /home on SSD and using RAID as additional storage. You can symlink any directories you need from RAID to /home, for example: music, video, etc; thus extending your /home capacity, and still (mostly) having SSD benefits. Also, it's easier to create backups/snapshots this way.

If you have enough RAM, consider moving caches (both user and system) to a compressed zram drive (yes, it's safe, though it'll increase loading time by ~1 second but prolong your SSD life a little): https://wiki.archlinux.org/title/Zram.

stfischr

Member

Registered: 2020-04-29

Posts: 18

Re: Configuration with RAID0

Hi.
I would note that a raid 0 with 2 HDDS doesn't really give you any meaningful speed increase over single disks. If you have certain workloads that manly do large sequential r/w operations it might be worth it but also remember that raid0 is dependent on every HDD, if one fails you are out of order until you replay your backups.
Like the 2 others said it is best to keep everything on the SSD and only store big files like movies on the HDDs. You can automate it with tiered storage solutions like bcachefs, this should give a bigger boost to your HDD speed but is also more work.

I don't think you really need 24 G swap unless you have some ram heavy workloads and not enough real RAM for it. I'm fairing pretty well with no swap and only 8 GB RAM (typical desktop usage).