Oracle RAC 12C on VirtaulBox 4.3.4 fails

[sivakumarnvn]

Hi

I have installed VirtualBox4.3.4 on my windows 7 Laptop which is intel core i7 with 12G DDR3 RAM.
Setup of two VMs with linux 64bit and runcluvfy.sh is successfull. During grid installation , installer install software on first VM and when starts remote installation on 2nd VM, Memory consumption more than 9G and finally 2nd VM errors out with low memory and hangs

Can you please let me know whether virtualbox4.3.4 is tested for oracle grid 12c ?
Kindly let me know if there any workarround or patches for this VM version

Thanks
siva

[noteirak]

I think you got the requirements order wrong. The question you should ask is : Does Oracle GRID 12C supports to be installed in a VM, Virtualbox in particular? AFAIK it is not.
You would need to take this with the Oracle DB support, not with the Virtualbox one.

[sivakumarnvn]

ok let me put in the other way

I have installed Vbox 4.3.4 and my PC and created two VM with linux V6.1 (64bit) each having 4.2G memory allocated ( my phiscal RAM size is 12G)
After i started installation either ORacle RAC or Oracle weblogic by keeping both VMs runing, 2nd VM hangs with GURU_MEDITATION and finally VM hangs

I have also tried with Vbox 4.2.18, even with this version 2nd VM hangs when the memory consumption goes up more than 9G , even though phyiscal memory is 12G

Do i need to change any cache sizes in windows 7 inorder to take full memory usage by Vbox

I hope i put my problem in right way now

[Ramshankar]

If you get a guru meditation please upload the corresponding VBox.log when it happened.

[sivakumarnvn]

If you get a guru meditation please upload the corresponding VBox.log when it happened.

Please find the VBOX.log file attached ..

[Ramshankar]

Although, I'm not the Windows expert, I remember we have/had problems with low-memory errors on Windows

The error is quite plain: "Unable to allocate and lock memory. The virtual machine will be paused. Please close applications to free up memory or close the VM".

Are you running several VMs in parallel all with high RAM assigned to it or do you get this even while you run a single VM with 4 GB? In any case, does reducing the memory assigned to the VM help?

[sivakumarnvn]

I have physical RAM of 12G and each VM i have allocated 4G ( 2 VMs created 4+4 = GB allocated ) and still there is 4G available for Host OS
even i tried to increase the VM memory to 3.5G but during the oracle installation , 2nd VM is hanging with low memory as soon as memory consumption crossed 9GB on host level ( saw this taskbar memory monitor )

[sivakumarnvn]

BTW .. I am runing both VMs together

[Ramshankar]

You could try pre-allocating the entire guest memory upfront (when the VM starts) and see if we're fighting for memory with your host. You start out with only 9 GB free, so can't be entirely sure if other things you may have running on your host may take up memory and push VirtualBox into out of memory situations.

You'll need to configure both your VMs with:

Code: Select all

VBoxManage setextradata <vmname> VBoxInternal/RamPreAlloc 1 

(Later if you wish to remove RamPreAlloc, run the same command without the " 1").

This will take a while to start up a VM as it will allocate all 4GB up-front rather than doing it on an 'on-demand' basis.

[sivakumarnvn]

Preallocating didnt worked at all..
Again 2nd VM crashed with GURU Mediation even though host has still 3+ G RAM free

Please let me know if there is any setting need to be changed for VBox to utilize complete memory

Note : I have opened only VBOX sessions there were no other sessions not even Chrome , i have dedicated complete 8G for 2 VMs and rest 4GB for host inorder to enable swap if needed

[Ramshankar]

Preallocating didnt worked at all..
Again 2nd VM crashed with GURU Mediation even though host has still 3+ G RAM free

Please let me know if there is any setting need to be changed for VBox to utilize complete memory

Note : I have opened only VBOX sessions there were no other sessions not even Chrome , i have dedicated complete 8G for 2 VMs and rest 4GB for host inorder to enable swap if needed

Could you please upload a log file with PreAlloc enabled?

[sivakumarnvn]

i lot the logs for that test..

Yesterday i did test by allocating 3.5G RAM for each VM ( 2x3.5G allocated ) and for physical host 5G available.
During the middle of installation , when i see task manager -> Memory monitor, i could see usage is 8G and available is 4G ( cache 2G and available 2G and Free 100M).
At this point of time , 2nd VM simply hangs some time and throughs out GURU MEDITATION error ( with low host memory ) , even though available memory is still 4G

During my tests, i always VBox is checking the FREE memory instead of available and cache memory on host and crashing ..
(and Example depiction of memory usage is attached ..=

Please let me know why VBox is checking Free memory instead of Avaialble & Cache memory ?
Is this bug with VBOx 4.3.4 ?
I even had same problem when i tried with VBox4.2.18 as well...

[michaln]

Please let me know why VBox is checking Free memory instead of Avaialble & Cache memory ?

Free/available/cache memory reports are ultimately all irrelevant, because the amount can change at any moment. What matters is that VirtualBox asks the host OS for memory and doesn't get it. At that point, it doesn't matter who reports how much "free" memory. If the memory can't be allocated, it's not there and nothing else matters.

I even had same problem when i tried with VBox4.2.18 as well...

That certainly sounds like your system just doesn't have enough available memory.

[Ramshankar]

Remember there is a bit of overhead besides just the allocated RAM for a VM process. It's not like if you assign 3.5 GB RAM to a guest that the VM process is hard limited to *exactly* that amount. I can't tell you what exactly the overhead is and can be slightly different between headless and GUI VMs too.

[sivakumarnvn]

Please let me know why VBox is checking Free memory instead of Avaialble & Cache memory ?

Free/available/cache memory reports are ultimately all irrelevant, because the amount can change at any moment. What matters is that VirtualBox asks the host OS for memory and doesn't get it. At that point, it doesn't matter who reports how much "free" memory. If the memory can't be allocated, it's not there and nothing else matters.

I even had same problem when i tried with VBox4.2.18 as well...

That certainly sounds like your system just doesn't have enough available memory.

Sorry as i wrote , my system has physical 12G memory ..
I am sure free/cache memory are relevant here, my quetion is not answered here .
Why VBox is crashing when already available memory 4g it shows in Task manager ?