﻿id	summary	reporter	owner	description	type	status	component	version	resolution	keywords	cc	guest	host
6242	VT-x causes massive DPC latency	maqr		"I am running Windows 7 x64 on a q6600 with virtualization enabled in the bios.  Whenever my guest (x64 or x86) is under any kind of load (even just booting the Ubuntu installer), I get big DPC latency spikes.  This is obviously a problem because it causes choppy audio, video, and generally degrades performance.  Once inside the guest OS, this is can be easily reproduced with a simple bash script: {{{ while true; do """"; done }}}

I have reproduced this on an i7 920 with the same problem.

Attached is a dpclat screenshot and a dump from xperf.  If the ETL would be beneficial in debugging, I could produce one.

The ""fix"" for me was to install a 32-bit guest and disable VT-x in the vbox options."	defect	closed	VMM	VirtualBox 3.1.4	fixed	DPC, VT-x		Linux	Windows
