Disk writing speed under KVM

[f33dm3bits]

# lsmod| grep kvm
kvm_intel 217088 8
kvm 598016 1 kvm_intel
irqbypass 16384 5 kvm

Yes than you are running in fullsystem emulation mode, if you hadn't gotten anything back you would have been running in user emulation mode. Now just for the sake of testing, what happens when you shutoff the running vm's and start the installation of the one you are currently trying to install that's taking days to complete?

 

[dos2unix]

To dos2unix.
"Generally you don't have more VMs than you do cores." - I'm absolutely sure that your opinion is full wrong. Now I have a lot of workable servers with dozens VM working on 4 or 8 cores CPU. Even 100 VM can be start on 2 core CPU and it will be working fine. Do you want to see screenshot from my another servers?

I didn't say it was impossible, I said it's not a good practice. I stand by that.
In my career I have managed literally thousands of VMs for large corporations,
While all of them "oversell" the CPU cores at one time or another, none of them
make a practice of running a production environment this way.

 

[AlexEv1337]

To dos2unix

I have opposite experience. I'm now administer of a couple of servers, see attachment for one of them please. This is server with 8 core and it working fine with 37 VM (98 days uptime). And I have now at least 3 servers working fine with uptime a YEARS, with the same relation VM/ProcessorCore > 10. And my opinion the best practice 10-20 Vm for one core processor, up to 50 VM for one core processor. This is a sense of virtualization, this is a best practice (for my opinion). Because that servers working fine, however my current server not working fine even with 2 VM. At common economic reason to rent this server (256 GB memory) start from 100-150 VM.

 

[AlexEv1337]

I have deleted all VM and reformat all disk and try again - created raw disk
with raw format working faster, but not enough
I see only 7 minutes but wait 20 and not see any progress

 

[AlexEv1337]

heh... and for each files time growing and growing

 

[AlexEv1337]

I want to summarize this topic andmy issue. I have googled about half of day similar issues and found about 70.000 pages with description similar to https://serverfault.com/questions/407842/incredibly-low-kvm-disk-performance-qcow2-disk-files-virtio - for that gay disk with speed 120 mb/c KVM reduced to 0.5 mb/c, in 240 times. In my case relation is even more. So, KVM soltion with qcow2 defined on existing file system is no more than scam and fraud.