ZFS vs RAID10

[bolzerrr]

Hi,

i wonder what setup would make most sense. Give the following situation:
Asrock N100M 32 gb RAM
- 1x NVME drive 512gb
- 1x SSD 512gb

Current setup: ZFS Raid 1 with both drives ~90% of the capacity. Spare 10% are used as cache or log for ZFS. I am not very happy with the performance therefore i have two ideas.

Idea: I still have a "DELL PERC H310"
1) I could create a RAID 10 by moving over the SSD and adding 3 more of the exsiting SSD, install ZFS on top and use the NVMe for caching and log
2) I could use the the RAID in HBA and install a ZFS RAID 10 and use the NVMe for caching and log
3) 2 Drives HW RAID 0 (or even 4 drives raid 10) + ZFS Raid 1 on top of it with the NVMe. Similar to current situtuation but hopefully the HW Raid would not slow down the NVMe on the ZFS raid.

My thought so far: Approach 1 would reduce CPU load as the controller is doing the raid calculations. Approach 2 because i was reading that ZFS might bring some other benefits when handling the raid directly. Both approaches i feel like wasting the speed of the NVMe.

I am also open for other ideas!

 

[cwt]

1) and 3) not advisable, see the PVE wiki (ZFS on RAID)

I would recommend 2). At the moment, your ZFS mirror won’t use the speed of your NVME because it‘s bottlenecked down to the slowest mirror member (SSD). And you should reconsider using a single drive for caching.

 

[bolzerrr]

Thanks for your hint, i even had a new idea: Put another NVMe which i have spare to a PCIe slot using a Sabrent PCIe m2 Adapter.
This would replace the SSD and hopefully provide better speeds. Cache and log would stay on separated partitions one of each of the drives.

Question is, would that be faster compared to scenario 2?

 

[leesteken]

In my experience recent ZFS versions do send more reads to the faster drive in a N-way mirror, and it does become faster when pairing an SSD with a couple of HDDs.

 

[floh8]

think of the energy consumption with the H310. At Home u dont need a Raid1, when u have a good backup. So use the nvme in the asrock for vms and lxcs and the ssd for backup. If u like u can install pbs alongside pve or use the intern backup utility.

 

[bolzerrr]

The energy aspect is also something i am considering: 4 SSD`s + H310 vs NVME riser card is expected to be significant considering a overall low energy environment.

Also in terms of invest the NVME is much lower compared to 3 extra SSD drives.
I didnt look into pbs yet, but will invertigate now.

There are two more HDD drives which can be used perfectly for backups.