JFYI: VirtualBox stable/unstable setteings (3.0.51.r22902)

In a month, I have been tried to investigate FreeBSD system
stable/unstable situations and factors around VirtualBox
bacause frequently my VirtualBox let FreeBSD freeze, panic
and fatal trap.

I guess my report is not strict comprehensive, but it's useful
and helpful for everyone who wants to use VirtualBox on FreeBSD.

   Tested environment:
     host os: FreeBSD 9-current amd64 (among 12/2009)
     virtualbox: virtualbox-3.0.51.r22902_3
     cpu: Intel Core2 Quad Q9550
     mem: 8GB
     video: GeForce 9800 GT

   Kernel settings:
     - Vimage lets FreeBSD freeze within VirtualBox bridge
       networking feature.

   VirtualBox settings:
     -------------------------------------------------------------
     |                         | effects on the host os stability|
     -------------------------------------------------------------
     | ACPI                    | NO                              |
     | IO APIC                 | NO                              |
     | PAE/NX                  | (not checked)                   |
     | Core numbers            | YES (*1)                        |
     | VT-x/AMD-V              | NO                              |
     | nested paging           | (not checked)                   |
     | 3D acceleration         | (not checked)                   |
     | IDE controller type     | NO                              |
     | Additional controller   | NO                              |
     | CD/DVD drive host       | NO                              |
     | CD/DVD drive image file | NO                              |
     | FDD drive host          | (not checked)                   |
     | FDD drive image file    | (not checked)                   |
     | Audio                   | (not checked)                   |
     | Network adapter type    | NO                              |
     | Network NAT             | NO                              |
     | Network bridge          | NO                              |
     | Network inner network   | (not checked)                   |
     | Network host only       | (not checked)                   |
     | Serial port             | (not checked)                   |
     | share folder            | (not checked)                   |
     | Guest OS sort           | NO                              |
     -------------------------------------------------------------

    (*1) Multicore attached virtual environment easily and frequently
        lets FreeBSD freeze.

   Hardware health:
     - Weakened PC power unit or less-power power unit leads PC
       very unstable condition. If you encounter non-reproducible
       error or panic, you should better to check your PC power unit.

     - Unstable memory leads FreeBSD system panic and fatal trap.
       If you encounter "segmentaion fault", "panic" or "fatal trap"
       error, shutdown system and check your PC memory health with
       memtest86+. (Ubuntu install CD has memtest86+ feature.
       Using Ubuntu as memetest86+ checker is reasonable way).
       If you have luck, updating BIOS and set DRAM settings for
       stable resolves this issue.

     - Hard Disk should be health. Check your disk status by
       smartmontools (sysutils/smartmontools).

   Driver:
     - NVIDIA driver (x11/nvidia-driver, nvidia-driver-195.22) leads
       FreeBSD freeze non-reproducibly. If you use both
       NVIDIA driver and VirtualBox along with non-reproducible
       FreeBSD freeze, use nv driver instead.


Recap points:
   - Check your PC health first, especially for Power unit,
     memory and Hard disk.
   - Remove Vimage if you want to use bridge networking feature
     of VirtualBox.
   - Use nv driver instead of nvidia-driver if you have FreeBSD
     non-reproducible freeze problem with nvidia-driver.

-- 
Daichi GOTO
CEO | ONGS Inc.
81-42-316-7945 | daichi_at_ongs.co.jp | http://www.ongs.co.jp
LinkedIn: http://linkedin.com/in/daichigoto