On 10/ 6/16 10:03 AM, Matthew Parsons wrote:
Have you installed the VirtIO drivers in windows? (And what version?) For testing I'd try disabling/removing the guest NICs and just see if interrupts die down.
Which version is often an issue! There are so many out there and some work with one version of windows and not another! The ISO I use is named "me-ws2012std-20130712.iso" and I've been using it for a couple of years so its origins are lost in the mists of time.
Also (again for testing) perhaps reduce cores to the amount on a physical CPU socket and assign/restrict to avoid crossing NUMA boundries.
The problem only becomes an issue when the core number gets high, as I said in my original post the load average almost quadruples when going from 16 to 32 cores.
(I trust that whatever workload you're running benefits from that many cores, but typically I'd keep 2 or so for the hypervisor/management/other.)
The workload is compiling a large C and C++ code base, so the more cores the better.
Experimenting on a smaller machine shows the build times to cores ratios reflect those on bare metal, that is if I give the VM the full system picture (using qemu_extra_opts) build times are about 25% faster than giving it the number of physical cores (using vcpus). For example to get optimum performance on a single quad core, use "vcpus": 1, "qemu_extra_opts": "-smp cpus=1,cores=4,threads=2".
Cheers, -- Ian. ------------------------------------------- smartos-discuss Archives: https://www.listbox.com/member/archive/184463/=now RSS Feed: https://www.listbox.com/member/archive/rss/184463/25769125-55cfbc00 Modify Your Subscription: https://www.listbox.com/member/?member_id=25769125&id_secret=25769125-7688e9fb Powered by Listbox: http://www.listbox.com
