Maximum CPU sockets

[stuartthebruce]

What are the prospects for increasing the maximum number of processor sockets for PVE VM from 4 to 8 or 16?

I have found that I can get more network performance out of Linux guests on hypervisors with 400G NICs by increasing the number of VM processor sockets from 1 to 2 to 4, and would like to try scaling further.

I am also interested in enabling hotplug memory but am currently limited by the initial VM boot with a hardcoded value of 1GB/socket so I might be able to enable hntplug memory on more guests if I can increase the number of sockets.

 

[alexskysilk]

I have found that I can get more network performance out of Linux guests on hypervisors with 400G NICs by increasing the number of VM processor sockets from 1 to 2 to 4, and would like to try scaling further.

Please share benchmarks. Until then, I am guessing that you eventually got the vm to address the socket housing the PCI link to the NIC. generally speaking, adding sockets does no harm AT BEST- and usually slows down the machine by introducing 100s to 1000s of unnecessary cycles for DMA handoffs.

So why have them at all? two reasons. For non VM use, its to allow more pci/ram lanes to a single namespace. in a VM, SIMULATE the behavior for development.