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Allocating over 4gb of RAM for a vm guest
Posted: 16. Apr 2012, 15:19
by hinto
Hi guys,
I'm running VirtualBox 4.1.12 r77245 on a MacProc with 10 gb of RAM.
It is running the 64 kernel (AFAIK)
System Information shows:
Software->Extensions:
Code: Select all
ACPI_SMC_PlatformPlugin:
Version: 4.7.5
Last Modified: 6/18/11 4:09 PM
Kind: Intel
Architectures: i386, x86_64
64-Bit (Intel): Yes
Location: /System/Library/Extensions/IOPlatformPluginFamily.kext/Contents/PlugIns/ACPI_SMC_PlatformPlugin.kext
Kext Version: 4.7.5d4
Load Address: 0x1671000
Valid: Yes
Authentic: Yes
Dependencies: Satisfied
VirtualBox will not allow me to allocate more than 3584 mb of RAM to any 64-bit enabled guest.
Is there a workaround?
Thanks.
-Hinto
Re: Allocating over 4gb of RAM for a vm guest
Posted: 16. Apr 2012, 15:22
by mpack
Allocate whatever memory VBox will accept, run the VM, then post the VM log file as a zipped attachment.
Re: Allocating over 4gb of RAM for a vm guest
Posted: 16. Apr 2012, 18:28
by hinto
Here's the log file created with the max ram I could allocate for a 64 bit Linux guest for my MacPro host.
-Hinto
Re: Allocating over 4gb of RAM for a vm guest
Posted: 16. Apr 2012, 19:13
by mpack
You posted the VBoxSvc log file, however it was the VM log file that I asked for. The VM log file is called "VBox.log" and can be found in the "Logs" subfolder of the VMs home folder.
Re: Allocating over 4gb of RAM for a vm guest
Posted: 16. Apr 2012, 19:23
by hinto
My fault.
-H
Re: Allocating over 4gb of RAM for a vm guest
Posted: 16. Apr 2012, 19:41
by Perryg
00:00:00.691 Host RAM: 10240MB RAM, available: 1836MB
00:00:00.832 RamSize <integer> = 0x00000000e0000000 (3,758,096,384)
You should shut some things down. You don't have enough available.
Re: Allocating over 4gb of RAM for a vm guest
Posted: 16. Apr 2012, 22:12
by hinto
I have 10 GB of ram... and If I shut everything down, but VirtualBox, I still cannot allocate more ram to the guest.
-Hinto
Re: Allocating over 4gb of RAM for a vm guest
Posted: 16. Apr 2012, 22:37
by Perryg
Doesn't really matter if you have a TB installed in the host, it is how much is available. If you have 1.5GB available and try to assign 4GB it is still not going to work.
Other than that we would need to see an active log where it has refused to allow more (after making sure you have 1.5 times 4GB or 6GB available.
Re: Allocating over 4gb of RAM for a vm guest
Posted: 17. Apr 2012, 11:29
by mpack
This issue seems to arise a lot on Mac OS X hosts. I wonder if Apple has implemented some kind of prefetch-alike feature, the difference being that the effect is visible in the available memory check that VBox uses? It's either that or runaway OS bloat.
@rinto: I assume you haven't configured a big ram disk or anything like that.
Re: Allocating over 4gb of RAM for a vm guest
Posted: 17. Apr 2012, 13:12
by hinto
@Perryg I completely understand the concept. I run a Win7 guest on a Linux host using VMWare.
@mpack no ramdisks.
-Hinto
Re: Allocating over 4gb of RAM for a vm guest
Posted: 17. Apr 2012, 14:48
by hinto
Just re-verified with everything shutdown. I cannot allocate more than 4GB to a vm guest. It looks like there's a 4gb hard limit on the MacPro
ProProcessor 2 x 3 GHz Dual-Core Intel Xeon
Memory 10 GB 667 MHz DDR2 FB-DIMM
Graphics NVIDIA GeForce 7300 GT 256 MB
Software Mac OS X Lion 10.7.3 (11D50d)
It looks like a bug.
-Hinto
Re: Allocating over 4gb of RAM for a vm guest
Posted: 17. Apr 2012, 15:11
by Perryg
AFAIK the only time there is a limit on the amount of RAM that can be allocated is 32-bit host and 64-bit guest.
Try booting the host while holding the 6 & 4 keys down on a Mac and see if that changes anything. Be sure that you have the amount of RAM available that you are trying to assign.
Re: Allocating over 4gb of RAM for a vm guest
Posted: 17. Apr 2012, 15:18
by michaln
hinto wrote:It looks like a bug.
Not really.
You're using the 32-bit kernel. With that, you will not get VMs bigger than 4GB (about 3.6GB is the limit).
Re: Allocating over 4gb of RAM for a vm guest
Posted: 17. Apr 2012, 15:24
by hinto
So Mac Pro isn't by default using the 32 bit kernel?
I thought:
Code: Select all
ACPI_SMC_PlatformPlugin:
Version: 4.7.5
Last Modified: 6/18/11 4:09 PM
Kind: Intel
Architectures: i386, x86_64
64-Bit (Intel): Yes
Location: /System/Library/Extensions/IOPlatformPluginFamily.kext/Contents/PlugIns/ACPI_SMC_PlatformPlugin.kext
Kext Version: 4.7.5d4
Load Address: 0x1671000
Valid: Yes
Authentic: Yes
Dependencies: Satisfied
Showed that I was.
-Hinto
Re: Allocating over 4gb of RAM for a vm guest
Posted: 17. Apr 2012, 15:28
by hinto
Ah... I think I see it. Let me force the 64-bit kernel.
Code: Select all
System Version: Mac OS X 10.7.3 (11D50d)
Kernel Version: Darwin 11.3.0
Boot Volume: Macintosh HD
Boot Mode: Normal
Computer Name: Bryan Boone's Mac
User Name: Bryan Boone (sasbeb)
Secure Virtual Memory: Enabled
64-bit Kernel and Extensions: No
Time since boot: 28 days 22:21
Looks like it's not the default.
-H