Difference between Oracle 32-bit and Oracle 64-bit

[Sushil Singh_1]

Hi All,
We are moving to Oracle 9.2 and I want to recommend to install 64-bit instead of 32-bit which we were using before. Ofcourse the question arises, what is the difference between Oracle 32-bit and Oracle 64-bit. We have HP-UX 11i 64 bit installed.

[Jeff Schussele · Accepted solution]

Hi Sushil,

Major difference would be more than a terabyte of addressable memory.
32-bit applications can only address 1.75Gb of memory - whereas 64 bit apps can address up into the Terabyte range.

Rgds,
Jeff

[A. Clay Stephenson]

If you have the option, 64-bit Oracle is the way to go. The biggest difference is that SGA's can now be huge -- many GB's --- and 9i really needs large SGA's to perform well. Of course, if your box only has 1GB of memory then you might as well stay in 32-bit land. A common misconception is that 64-bit code executes faster; it doesn't. You should really think of it as a resource enhancer rather than a performance booster. However, because caches and other data structures can be much larger in 64-bit land then the overall performance can increase dramitically over its 32-bit counterpart.

[Michael Steele_2]

Oracle will preloads its SGA with large objects, or, provide a means for loading very large objects. This caching scheme is for better performance.

32 bit has memory limitations that make this large object pre-loading more difficult.

64 bit also allows for much larger shared memory which newer versions of oracle rely upon.

[Sushil Singh_1]

Thank you guys,
I think now I have something to make my case for 64-bit Oracle.

Thanks
Sushil Singh

[Steven E. Protter]

There is a procedure you MUST run on the data to convert word size from 32 bit to 64 bit.


Attaching it.

SEP

[Jean-Luc Oudart]

As far as I know Oracle9i on HPUX is 64bits.
Nevertheless, the client software can be either 32 or 64 bits. You just have to choose the right PATH for the libclntsh.sl



http://forums1.itrc.hp.com/service/forums/parseCurl.do?CURL=%2Fcm%2FQuestionAnswer%2F1%2C%2C0xc835349f786acc4ab21d36da9d59a127%2C00.html&admit=716493758+1066231747046+28353475

Rgds,
Jean-Luc

[Yogeeraj_1]

hi,
-
I would simply add:
A 64bit OS would allow us to address much more memory then a 32bit one. On a 32bit system (a system where pointers are 32bits) we can address 4gig or less of RAM. That limits the size of an SGA. On a 64bit system -- we can address an incredibly large SGA.
-
hth
Yogeeraj