KQEMU 1.3.0pre10 released - under the GPL

Posted Feb 7, 2007 12:26 UTC (Wed) by 01101010 (guest, #43187)
In reply to: KQEMU 1.3.0pre10 released - under the GPL by irios
Parent article: KQEMU 1.3.0pre10 released - under the GPL

There will not be a winner, different virtualizers exist for different needs. Do you need complete emulation of an x86-system on any architecture? Only Bochs provides that, because it simulates a PC using C. But it is slow. If your CPU is supported by QEMU, which recompiles some code on the fly, it will not be that slow. Qemu can emulate different CPUs, not only x86. The common case of emulating x86 on x86 can be faster using native code execution when possible. KQemu and virtualbox do that (both extend qemu). Does your CPU support VT? Use KVM, then Qemu just has to emulate the hardware around the CPU. Dont want a full OS on top of the emulated machines? Xen provides that, also using VT and Qemu. Can still be faster if your guest os can be ported to the virtualizer, so you don't have to emulate complete hardware. Xen can do that. lguest uses a usual linux kernel as the hypervisor instead of Xen, but is slower and does not have all the interesting features Xen has (SMP, live migration). User mode linux is a port running as a userspace process, but cannot reach the speed of Xen. Sometimes you don't even want seperate kernels, just isolated userspace environments. That saves ram and is easier to manage. OpenVZ provides that.

So I think Qemu, either Qemu+KQemu or Virtualbox, Qemu+KVM, Xen, Xen+VT+Qemu, OpenVZ and something like lguest will stay alive for a long time, because each has a different approach. But that seems to be a full panorama.