NVME and SQL

[john60]

I have an SQL database running on a Kubernetes pod on a Ubuntu server with NVME drives and would like to move it to Truenas scale.

In TrueNAS scale, I installed MySQL, and launched the Docker image using a hard disk and everything appears to work, just slower. So now I would like to move the NVME to see if I can get back my performance loss.

Q1: Is a single NVME with no redundancy supported on Truenas/ZFS?
Q2 : How much slower is qty 3: NVME with Z1 redundancy than qty 1 NVME without redundancy? I understand the loss of redundancy, interested in speed.
Q3: qty 2: Speed compare of qty 2 NVME with mirror vs qty 3 NVME in Z1 configuration?
Q4: Can I mount ext4 in TrueNAS to copy over the data?
Q5: Is an NVME Cache drive useful for NVME disks?

Thank you in advance for your suggestions.

 

[sretalla]

Q1: Is a single NVME with no redundancy supported on Truenas/ZFS?

Works technically, but isn't recommended (perhaps "supported") due to lack of redundancy. Your data... your decision.

Q2 : How much slower is qty 3: NVME with Z1 redundancy than qty 1 NVME without redundancy? I understand the loss of redundancy, interested in speed.

Depending on what you're measuring, maybe the same... IOPS would be no different, throughput may be more/faster on RAIDZ1.

Q3: qty 2: Speed compare of qty 2 NVME with mirror vs qty 3 NVME in Z1 configuration?

You're splitting hairs here... it's unlikely you would see a lot of difference to either IOPS or throughput, but the mirror is clearly cheaper. iX has an article somewhere on their blog site comparing different VDEV types and performance... here it is: https://www.ixsystems.com/wp-conten...age_Pool_Layout_White_Paper_February_2022.pdf

Q4: Can I mount ext4 in TrueNAS to copy over the data?

Not easily (ext2 is the latest supported version). Better to move data across the network.

Q5: Is an NVME Cache drive useful for NVME disks?

Probably not. More RAM would certainly be more helpful.