Whats the difference between machines performance-x tiers and appsv1 dedicated-x tiers? Are they the same with different naming or are the cores no longer dedicated in machines?
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The cores aren’t dedicated, but they’ll perform better than the dedicated Nomad VMs do. Machines are much better are finding idle cores for an app.
Dedicated cores didn’t work the way we wanted. People will occasionally hit issues when hosts are under extreme load, and I think calling them dedicated made that a nasty surprise.
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Are you able to provide any insight as to how the performance machine cores perform better than the dedicated nomad cores? Is there some scheduling magic going on? Or is it that they just better utilize idle cores?
Yeah we pinned dedicated VM CPUs to specific hardware threads. performance machines can move the virtual CPUs to any available hardware thread on the host. Our new hosts have up to 256 hardware threads, so there’s a lot of room to let the hypervisor do magic.
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Awesome! In the case of heavy workloads needing to use a full core, will the full core be available to machines with performance cores? Or will they still share the core with other machines?
I am giving you cagey answers here because there are a bunch of edge cases. But yes, you will almost always get the full hardware capability.
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Interesting.
Within a NUMA node, or freely across all processors? Or, you mean to say Machines may move across processors between stop / start cycles?
From what I understand, it is still a vCPU (hardware thread), not a “core”.