Opened 15 years ago
Last modified 11 years ago
#6242 closed defect
VT-x causes massive DPC latency — at Initial Version
Reported by: | maqr | Owned by: | |
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Component: | VMM | Version: | VirtualBox 3.1.4 |
Keywords: | DPC, VT-x | Cc: | |
Guest type: | Linux | Host type: | Windows |
Description
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.
DPClat screenshot