Bug 845751

Summary: qemu virtualization extremely slow
Product: [Fedora] Fedora Reporter: Rui Mota <rmomota>
Component: qemuAssignee: Fedora Virtualization Maintainers <virt-maint>
Status: CLOSED NOTABUG QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: high Docs Contact:
Priority: unspecified    
Version: 17CC: amit.shah, berrange, cfergeau, dwmw2, itamar, knoel, pbonzini, rjones, scottt.tw, virt-maint
Target Milestone: ---   
Target Release: ---   
Hardware: i686   
OS: Linux   
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2012-08-04 11:07:23 EDT Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: ---

Description Rui Mota 2012-08-04 10:59:29 EDT
qemu is extremely slow when running a CPU that does not support virtualization.
The virtual machine performance makes it impossible to work with.
But when using another product like vmware the virtual machine performs very good.
My laptop is not that old but unfortunately it does not support virtualization.
The command:
egrep '^flags.*(vmx|svm)' /proc/cpuinfo

brings nothing.
It would be very useful for my daily work if qemu works as well as vmware.

How reproducible:
Never worked fine as long as I remember.
I keep switching to vmware every release of qemu I try hoping that some day some one will look at vmware code and implement the same algorithm.

Steps to Reproduce:
1. create a vm in a CPU that doest not support virtualization.

Actual results:
Super slow virtual machine and impossible to work with.

Expected results:
Should work as well as vmware as the system configuration is the same.
Comment 1 Richard W.M. Jones 2012-08-04 11:07:23 EDT
There's no possible way we can solve this in Fedora.

I won't even suggest that you take it up with upstream
qemu unless you have a huge set of patches and/or a
radical new approach.