I have had difficulty with Disk I/O performance with a Windows 2008 SR2 guest on a linux server.
My question is, is this a known issue (I'm guessing with I/O APIC)?
Here are the details of guest and host...
I've been testing Windows 2008 SR2 guest with the following:
* VirtualBox 4.1.2
* 200 gig VDI fixed size disk image
* 16gig of RAM
* 12 x CPU cores
The host machine is a Debian server with 2 x Xeon E5620 CPU, SSD disks.
* Debian lenny
* 2 x Xeon E5620 (effectively 16 cores)
* 24gig ram
* 4 x 120gig SSD's running in a RAID5 configuration.
My problem is that it seems the more Cores I enable on the Guest the slower the disk performance is.
Here is the disk performance on the guest running with 10 cores enabled using a dumb little disk tool called CrystalDiskMark.
Here is it running with 6 cores enabled.
Here it is with 2 cores enabled.
And for reference here is a small Windows XP guest machine on the same Host server with a single core.
Here is the Virutalbox Windows 2008 SR2 Guest config with 12 CPU Core's enabled.
Code: Select all
Name: cssp
Guest OS: Windows 2008 (64 bit)
UUID: 2c4d6076-0600-409f-b0d7-107db135b4e0
Config file: /home/sysadmin/.VirtualBox/Machines/cssp/cssp.xml
Snapshot folder: /home/sysadmin/.VirtualBox/Machines/cssp/Snapshots
Log folder: /home/sysadmin/.VirtualBox/Machines/cssp/Logs
Hardware UUID: 2c4d6076-0600-409f-b0d7-107db135b4e0
Memory size: 16384MB
Page Fusion: off
VRAM size: 16MB
CPU exec cap: 100%
HPET: off
Chipset: piix3
Firmware: BIOS
Number of CPUs: 12
Synthetic Cpu: off
CPUID overrides: None
Boot menu mode: message and menu
Boot Device (1): Floppy
Boot Device (2): DVD
Boot Device (3): HardDisk
Boot Device (4): Not Assigned
ACPI: on
IOAPIC: on
PAE: off
Time offset: 0 ms
RTC: local time
Hardw. virt.ext: on
Hardw. virt.ext exclusive: on
Nested Paging: off
Large Pages: off
VT-x VPID: on
State: powered off (since 2011-09-13T10:10:57.655000000)
Monitor count: 1
3D Acceleration: off
2D Video Acceleration: off
Teleporter Enabled: off
Teleporter Port: 0
Teleporter Address:
Teleporter Password:
Storage Controller Name (0): IDE Controller
Storage Controller Type (0): PIIX4
Storage Controller Instance Number (0): 0
Storage Controller Max Port Count (0): 2
Storage Controller Port Count (0): 2
Storage Controller Bootable (0): on
Storage Controller Name (1): Floppy Controller
Storage Controller Type (1): I82078
Storage Controller Instance Number (1): 0
Storage Controller Max Port Count (1): 1
Storage Controller Port Count (1): 1
Storage Controller Bootable (1): on
Storage Controller Name (2): SATA Controller
Storage Controller Type (2): IntelAhci
Storage Controller Instance Number (2): 0
Storage Controller Max Port Count (2): 30
Storage Controller Port Count (2): 3
Storage Controller Bootable (2): on
IDE Controller (1, 0): /usr/share/virtualbox/VBoxGuestAdditions.iso (UUID: 10efa78a-1f35-4431-a8bf-12c8130c0bd0)
SATA Controller (0, 0): /home/sysadmin/.VirtualBox/HardDisks/cssp.vdi (UUID: 3d445880-5a1d-413d-a676-7593c1c34425)
SATA Controller (2, 0): /home/sysadmin/.VirtualBox/HardDisks-nas/cssp-backup.vdi (UUID: b02a4236-0b56-4694-911f-ac2aad129332)
NIC 1: MAC: 08002760E77C, Attachment: Bridged Interface 'eth0', Cable connected: on, Trace: off (file: none), Type: 82540EM, Reported speed: 0 Mbps, Boot priority: 0, Promisc Policy: deny
NIC 2: disabled
NIC 3: disabled
NIC 4: disabled
NIC 5: disabled
NIC 6: disabled
NIC 7: disabled
NIC 8: disabled
Pointing Device: PS/2 Mouse
Keyboard Device: PS/2 Keyboard
UART 1: I/O base: 0x03f8, IRQ: 4, attached to device '/dev/ttyS0'
UART 2: disabled
Audio: enabled (Driver: Null, Controller: HDA)
Clipboard Mode: Bidirectional
VRDE: disabled
USB: disabled
USB Device Filters:
Index: 0
Active: yes
Name: Agere Systems Agere USB2.0 V.92 SoftModem [0200]
VendorId: 047e
ProductId: 2892
Revision: 0200
Manufacturer: Agere Systems
Product: Agere USB2.0 V.92 SoftModem
Remote: 0
Serial Number:
Available remote USB devices:
<none>
Currently Attached USB Devices:
<none>
Shared folders: <none>
VRDE Connection: not active
Clients so far: 0
Guest:
Configured memory balloon size: 0 MB
OS type: Windows2008_64
Additions run level: 0
Guest Facilities:
No active facilities.