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Re: Max sessions With Oracle SE

From: Anton Buijs <>
Date: Thu, 11 Jul 2002 21:25:50 +0200
Message-ID: <agkm1c$l06$>

I don't fully understand what you are trying to say. On OTN choose download, scroll down to the bottom, under Archived products choose 8i.
Oracle 8.1.7 EE 64-bit for HP-UX is available for download, not 32-bit, not SE.

The only reason I can think of why Oracle recommends EE that is "well designed to support high load" is because they get more (much more) license fee and it has some options for scalability and so. Not said that SE could not do the job, but it also depends on if and how your application can use these options.

Do you need 64-bit or do you really need 32-bit? Don't understand what you wrote.
I've read that 64-bit is not always better/faster than 32-bit. It takes more memory because a word is always 64-bit, also where 32-bit would be sufficient. These kind of arguments.....

Maybe the machine is to0 small for 2 databases with so many users. One should be ok.
It also depends on how big the SGA need to be. Java, many stored procedures, triggers etc.. need big java_pool and shared_pool_size. How many db_block_buffers are needed to prevent performance degradation due to heavy I/O?
These 3 parameters determine most of the SGA size. Enough memory must remain for the Operating System and the server processes.

Given the limited amount of memory for 300 concurrent user sessions (as a rule of thumb 1-2 Mb/server?) I would choose for MTS initially, reducing the number of active (shared) server processes to let's say 2 or 4 for every database. Don't start too much shared servers. The only result is they start fighting for the CPU.
I have experienced on a Sun 10K box with 8 CPU's, a V8.0.5 database running MTS and 200-300 concurrent users that it runs better with 12 shared servers than with 20. So shared servers = 1.5 or 2 * #CPU's. It appeared to be more efficient to let dispatchers wait on a free shared server than have more concurrent active shared servers that get kicked of the CPU by the operating system (expensive context switches) every x milliseconds, waisting about 10% of CPU power in system time.
Since you have much less CPU's I don't want to clain this formula scales down to this number, but never the less I think I should share this experience with you.

XAV <> schreef in berichtnieuws 3d2d696d$
| Tx for the feed-back !
| I found both release (32b and 64b) for Oracle 9i on oracle site
| (
| but not for Oracle 8i :
| avaible to download
| --------------------------------------------------------------------------

| Oracle9i Database Release 2 Enterprise/Standard Edition for HP 9000
| Series HP-UX
| Download the Complete Files
| server_9201_hpunix64_disk1.cpio.gz (566,419,019 bytes)
| server_9201_hpunix64_disk2.cpio.gz (648,282,885 bytes)
| server_9201_hpunix64_disk3.cpio.gz (538,652,554 bytes)
| server_9201_hpunix64_disk4.cpio.gz (37,595,939 bytes)
| --------------------------------------------------------------------------

| If I well remind, we were obliged to migrate to Oracle 8.1.6 64 bits
| because we got libraries incompatibility on HP-UX 64 bits ...
| So I'm really afraid to switch to Otacle 32 bits !
| So I really don't know what to do with such big support difference
| between both release.
| And theremore, I planned to host 150 sessions on 2 Databases but on a
| single server, that's mean 300 concurent sessions.
| The server is an HP L3000 / Biproc / 2Gb RAM.
| Xavier
| "Anton Buijs" <> wrote:
| >In Oracle 8i Getting to know Oracle, Chapter 5, there is an extensive
| >overview of options available in Standard Edition, Enterprise Edition and
| >Personal Edition.
| >I tried to find if MTS (Multi Threaded Server) is available in SE, but is
| >not listed. Therefore I guess it is.
| >With 150 users you may have better results using MTS.
| >As far as I have seen there is no 64-bit SE, only EE. But 32-bit also run
| >a 64-bit OS.
| >When you don't need the EE features I think you can run V8.1.7.3 SE
| >if there is enough memory and CPU power.
| >XAV <> schreef in berichtnieuws
| >3d2afb8f$
| >| Hello,
| >|
| >| Oracle told us that the Entreprise Edition (compare to SE) is well
| >| designed to support high load. Is it true ?
| >| I planned to use a Standard Edition ( 64b on HPUX 11.00 64b)
| >| with an Oracle Server hosting 2 databases of 150 concurent sessions
| >| max (for each DB).
| >| Is it realistic ?
| >|
| >| Tx
| >| Xavier
| >|
Received on Thu Jul 11 2002 - 14:25:50 CDT

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