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Running Oracle VM Virtualbox as 64-bit guest OS in 32-bit host OS

SadockDec 15 2011 — edited Dec 16 2011
Dear all

I get this error *'long mode not supported, rebooting Press any key to reboot'* when trying installing Solaris 11 from Oracle Solaris 11 11/11 Live Media for x86 on my 32-bit laptop. When i find solutions on Internet (oracle forums) i get siggestions that Oracle Solaris 11 is only supported on 64-bits

But also i get another suggestion that say 'Another clarification: what is mandatory for Solaris 11 on the top of Virtual Box is defining the former as a 64-bit guest, the host can stay 32 bit"

For me i interpreted this suggestion as is possible to run Oracle VM Virtualbox as 64-bit guest OS in 32-bit host OS. Community is it really possible? if possible how?

Regards

Sadock

Comments

Dude!
Answer

Yes. Each database will require its own SGA segment and additional databases will add too the total size required. POSIX or /dev/shm shared memory is similar to a RAM disk, which maps memory to virtual files to be shared among processes. By default, the maximum size of /dev/shm is 50 % of the physical or installed RAM. It does however not reserve or allocate RAM other than what is actually being used.

Keep in mind that Oracle database AMM and /dev/shm are not recommended for large memory configurations. As I recall, if your SGA is greater than 2 GB, you should use kernel hugepages instead. Kernel hugepages are more efficient due to larger memory pages, which requires far less resources for memory management and results in much better performance.

An Oracle database instance can use SYS V shared memory, which is either kernel hugepages or conventional 4k memory pages, but cannot use POSIX /dev/shm for SGA and SYS V at the same time. You can however use different shared memory concepts for different Oracle database instances on the same server. For example, running an +ASM instance using AMM and another Oracle database using kernel hugepages and ASMM.

Speaking of shared memory, the SHMMAX kernel parameter applies to SYS V shared memory only. It's a safeguard parameter to limit how much shared memory a process can possibly use and needs to be large enough to fit the largest SGA of any of your Oracle databases. SHMMAX for a server that runs Oracle database is typically set to 4 TB or whatever the platform being x86 or x64 theoretically supports. SHMMAX does not apply to POSIX /dev/shm and Oracle AMM.

For more info, see the following:

https://docs.oracle.com/cd/E11882_01/server.112/e10839/appi_vlm.htm#UNXAR385

Btw, if you have to use OS release 5, use 5.11 at least. There is no reason to run 5.6, which is obsolete.

Marked as Answer by Jhil · Sep 27 2020
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Locked on Jan 13 2012
Added on Dec 15 2011
#oracle-virtualization, #oracle-vm-server-for-x86
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