Are there any distributed POSIX filesystems which don’t suck? I think part of the issue is that POSIX compliant filesystem just doesn’t scale, and you are just seeing that?
I think Lustre works fairly well. At the very least, it's used in a lot of HPC centers to handle large filesystems that get hammered by lots of nodes concurrently. It's open source so nominally free although getting a support contract from specialized consulting firm might be pricey.
You're going to have to open the image and then go to the third image. I thought it was interesting that OCI pegs Lustre at 8Gb/s and their high performance FS at much higher than that... 20-80.
Basically, we are building this at Archil (https://archil.com). The reason these things are generally super expensive is that it’s incredibly hard to build.
weka seems to Just Work from our tests so far, even under pretty extreme load with hundreds of mounts on different machines, lots of small files, etc... Unfortunately it's ungodly expensive.