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Comment by SPascareli13 | Hacker News Reader

> We have all databases in k8s, with physical volumes backed by an NFS-connected storage that's sitting in the same rack.

I was searching about this yesterday, how is your performance running a database in NFS? If your entire db can fit into the RAM cache it's probably fine, but when you have to do heavy IO is what I worry about with NFS.

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I think it depends on your NFS. A storage appliance with NFS hardware offload will work much better than a software NFS.

Personally with bare metal database I'd try to do fibre channel if supported, then iscsi. Would only dabble with NFS if it had hardware offload, but even still I think block storage would have better iops.

AFAIK the reason for using NFS is that it's supported in k8s out of the box. I don't recall any performance issues for the things that we're doing. When we had database issues, it was the usual stuff: missing indexes, suboptimal config settings etc.

Could you explain what do you mean by "NFS hardware offload"?

Google search points mostly to VMWare-specific "VAAI NAS framework", which doesn't seem to be useful in case of database over NFS.

Some storage appliances have special hardware to accelerate NFS operations. Those may be able to come close to the same performance as a block storage device.

The other option with NFS is running it in software such as a NFS server on Linux configured with /etc/exports and backing the data to a block storage device. This is CPU intensive and would be much slower under load.

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