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>> What's good for one user may be bad for another I bought 3 "identical" old Dell T3610 workstations off eBay for a home lab project. They have "identical" st

>> What's good for one user may be bad for another I bought 3 "identical" old Dell T3610 workstations off eBay for a home lab project. They have "identical" striped HDDs in them. Kicking off a Fedora Core OS install on all 3 simultaneously (which i've had to do a few times as i learned how ignition works) results in the same ordering of the hosts finishing their rebuilds - Machine 2 always finishes first by around 3 minutes of a 14 min wipe & reinstall process. Machine 3 finishes ahead of machine 1 by around 45 seconds or so usually. Almost 5 minutes in a <20 mins process, that's huge! I still don't actually know the root cause. Benchmarking disk I/O has them within a few percent of each other. It's not that they're contending to remotely load the OS installer - that gets cached in memory at the start. There's a few seconds difference in the UEFI bios startup timings but none of them are particularly consistent which is weird, i would have thought UEFI init time would be the same on a given host each boot, but there's a few seconds in it each time.

userbinator 5y ago
There's a few seconds difference in the UEFI bios startup timings Could that be anything to do with the Intel ME or similar "management" spyware/etc. trying to phone home or do something? You may have to reflash the BIOS to "clean" that completely. The other thing I can think of is that the CPU heatsinks aren't clogged with the same amount of dust and causing one machine to thermally throttle more than the others.
- xen2xen1 5y ago
  Thermals are probably the right answer.
bentcorner 5y ago
That's interesting. If you're curious, swapping disks might tell you more. If it's thermals like other commenters have suggested then you won't see a difference. (unless you knock some loose!)
bityard 5y ago
I used to work at a web hosting company and one of my responsibilities was managing all the VPS backups. We had a few racks for "backup servers" which were all identical boxes. We would provision CentOS on them two or three at a time and I observed the exact same thing. Some servers were always just a little faster than others. Never figured out why.

userbinator 5y ago

There's a few seconds difference in the UEFI bios startup timings Could that be anything to do with the Intel ME or similar "management" spyware/etc. trying to phone home or do something? You may have to reflash the BIOS to "clean" that completely. The other thing I can think of is that the CPU heatsinks aren't clogged with the same amount of dust and causing one machine to thermally throttle more than the others.

xen2xen1 5y ago
Thermals are probably the right answer.

bentcorner 5y ago

That's interesting. If you're curious, swapping disks might tell you more. If it's thermals like other commenters have suggested then you won't see a difference. (unless you knock some loose!)

bityard 5y ago

I used to work at a web hosting company and one of my responsibilities was managing all the VPS backups. We had a few racks for "backup servers" which were all identical boxes. We would provision CentOS on them two or three at a time and I observed the exact same thing. Some servers were always just a little faster than others. Never figured out why.