Operating System - HP-UX
1748060 Members
5612 Online
108758 Solutions
New Discussion юеВ

Re: How much 32bit Oracle 8i is slower then 64bit one ?

 

How much 32bit Oracle 8i is slower then 64bit one ?

Hi All !
We're going to use 32bit Oracle 8i EE on HP-UX 11i platform (rp7410 system). This is because our software developers haven't tested their products on 64bit version of DBMS. My understanding, using 32bit version of DBMS on 64bit OS is wasting of processors' resources.
Does anybody know any official HP or Oracle's document which the differeces between 32bit and 64bit systems is described ?
Thanks in advance.
8 REPLIES 8
Steven E. Protter
Exalted Contributor

Re: How much 32bit Oracle 8i is slower then 64bit one ?

32 Bit Oracle may actually be faster.

64 bit programs can address larger memory addrsss spaces, but each instruction is larger than 32 bit Oracle.

For very large databases, there is probably a significan advantage to using the 64 bit version of Oracle. Properly tuned, howeve the 32 bit version will work just fine.

The place for the oracle docs is:

http://otn.oracle.com

If you have an id
http://metalink.oracle.com

We're running on L class boxes with the 64 bit database and the 32 bit version of Oracle's ias. We are getting acceptable performance.

Good Luck, hope this helps.

SEP

Steven E Protter
Owner of ISN Corporation
http://isnamerica.com
http://hpuxconsulting.com
Sponsor: http://hpux.ws
Twitter: http://twitter.com/hpuxlinux
Founder http://newdatacloud.com
twang
Honored Contributor

Re: How much 32bit Oracle 8i is slower then 64bit one ?

I have installed both 32-bit and 64-bit oracle database server on hppux 11.11, in my own experience, running 64-bit oracle on hpux 11i is actually slower than 32-bit. 64-bit oracle doesn't really improve its performance.
Indira Aramandla
Honored Contributor

Re: How much 32bit Oracle 8i is slower then 64bit one ?

Hi,
HP-UX (64-bit): Oracle 32-bit vs 4-bit?
-------------------------------------------------

If we do not need 64-bit features for performance we should stay with 32-bit application code. The most obvious reason is better fitting processor's cache due to smaller pointers, etc. According to HP documentation, the performance degradation of a 64-bit application from the corresponding 32-bit application is the expected behaviour. The most preferred and advisable configuration is HP-UX 64-bit as a platform for running 32-bit code application/Oracle RDBMS.

A good reason for running 64-bit Oracle on HP-UX is the real need for large SGA beyond 1.75 GB. That is the limitation of addressing of shared memory in 32-bit architecture by executable with EXEC_MAGIC flag.

NOTE: While running 32-bit code on HP-UX 11.x (64-bit) we should remember that separate kernel parameters may affect limits for 32-bit and 64-bit executables. Particularly it means limits of segment sizes: text, data, stack and shared memory. All 64-bit related limits have _64bit postfix.

I hope this gives some idea.
Never give up, Keep Trying
Yogeeraj_1
Honored Contributor

Re: How much 32bit Oracle 8i is slower then 64bit one ?

hi,

Apart from the issue of larger SGA, there are a lot more Advantages offered by Oracle 64 bit or 64 bit Systems. You may find this article on Metalink very helpful. Attached: Note 107201.1 (ORACLE 64-bit ADVANTAGES).

Also note that, starting with Oracle 9i 32-bit support has stopped!

hope this helps!
Regards
Yogeeraj
No person was ever honoured for what he received. Honour has been the reward for what he gave (clavin coolidge)
Khalid A. Al-Tayaran
Valued Contributor

Re: How much 32bit Oracle 8i is slower then 64bit one ?


Hi,

You don't need to worry about Oracle on a 64-bit env. The performance is good. You have to search in Oracle's site for specific information. 32-bit applications may or may not run better in a 64-bit env.
Bill Hassell
Honored Contributor

Re: How much 32bit Oracle 8i is slower then 64bit one ?

Given a small SGA (less than 1GB) for both versions of Oracle, there is very little difference. However, 32bit Oracle (like all 32bit programs) cannot utilize large shared memory areas and iwth a good DBA, the SGA might be set to 4 to 12 Gb and 64bit Oracle will very much faster than 32bit Oracle! This is because the 32bit programs cannot use such large areas and may need to perform row insertions, temp sorts and other large data operations on disk rather than in RAM.

I would be very concerned for vendors and developers that do not support 64bit versions of their code with HP-UX! Nov 1997 (the date 64bit HP-UX was released) is a very long time ago.


Bill Hassell, sysadmin
Hein van den Heuvel
Honored Contributor

Re: How much 32bit Oracle 8i is slower then 64bit one ?

Whether Oracle is using 32-bit or 64 bit on the server side should be, and will be, entirely transparent to the application, shielded by SQL*net.

Using 64 bit will allow for large(r) SGAs. More pool to cache parsed cursors in ('cursor_space_for_time'), more sessions, more buffers to cache data in. ('alter table cache' for extreme cases.)
For a quick indication as to whether a large(r) db_block_buffer will help your applicaiton review the Read IO rate for your tablespaces.
Rita C Workman
Honored Contributor

Re: How much 32bit Oracle 8i is slower then 64bit one ?

We are running here on our 11i/64bit O/S all our Oracle database at 32bit.

One of our biggest databases finally got upgraded from 7.3.4 to 8.1.7 (still 32bit Oracle), and we found that we noted improvement overall, especially on our big batch jobs.

Rgrds,
Rita