Re: Oracle RAC on Win vs. Oracle on Linux

From: Niall Litchfield <>
Date: Tue, 23 Feb 2010 09:11:30 +0000
Message-ID: <>

Hi Dick,

First of all let me say that none of what follows is intended as a slight on either the decision you describe below which is perfectly fair and reasonable, nor the skills and competence of your wider team about which I know nothing. I'm really just using your post as a jumping off point to remake some of my argument in the new Oak Table press book and to comment on more general practice in the industry.

The points you make (apart from the "blue screen of death") apply to 32bit Oracle on Windows. Strictly of course they also apply to 64bit Oracle on 64bit windows and when 8Tb of memory becomes a limiting factor for our databases then the same problems will apply there as well, this day is a way off - I'm hoping past my retirement but I doubt it, I expect to be seeing 128bit computing (and 64bit shops busy windowing into a 128bit address space in a mad attempt to avoid just using the right hardware and software in the first place then). 32bit windows is limited by the architecture to a relatively few number of concurrent sessions ( low hundreds typically) and to relatively low memory requirements as you describe -- and because each new connection uses 1mb of memory by default whether it's doing anything or not these two restrictions have become rather limiting <rant> especially as web developers can't close connections reliable when not needed</rant>.

The proper solution here is not necessarily to jump ship to *nix, though that might be a perfectly reasonable decision for other reasons, but simply to move to 64bit computing of whatever flavour. After all it's extremely likely that your server and os have been running on 64bit hardware for some years now. What I do see often that really annoys me, though again I'm not suggesting this is your specific suggestion, is that *nix 64bit - especially Linux x86-64 - is superior to win32 because of the process and memory limits of the latter. Well doh! It is true that *in a limited environment* because of the process vs thread architecture Linux x86 is superior to win32 but then I'd be amazed if people were installing 32bit Linux either for much of the same reasons. It really isn't the 90s any more.

If you really mean that you have an actual blue screen of death that frequently, it really ought to be resolvable and certainly shouldn't have anything to do with Oracle itself since this is caused (primarily) by kernel address space bugs in drivers or other kernel mode software (so I guess crs could cause a BSOD). Your expectation should be that a BSOD should never be seen on a server running windows 2003 or later and rarely on windows 2000 and that any such occurrence should result in a support ticket with either or both of the hardware vendor and/or microsoft themselves.

Robert's original question was about RAC. I'd go back here to the comments in the other thread about RAC beng more complex and prone to human error than vanilla Oracle, and add that because of the clusterware and internetworking requirements it presents much more of an o/s management challenge than a vanilla o/s install, for that reason primarily I'd agree with the other posters who have commented upon where the skills of the system administration staff lie. Windows RAC in the hands of a Solaris SA is likely to be a disaster as is the reverse case.

On Tue, Feb 23, 2010 at 2:02 AM, Goulet, Richard <
> wrote:

> Rafiq,
> As I'm working in one of the premier (top 10) trials companies to the
> pharma community we are moving all our databases/applications off of Windows
> for Unix based operating systems. These are validated, no problem. Windows
> has two basic problems, memory and processes. Without a start up switch
> your limited to 3GB total memory for Oracle, with the switch you can have
> another gb, but it uses memory context switches which are a performance
> killer. The second is that Oracle on Windows is multithreaded within a
> single executable where as Unix based systems have multiple processes again
> limiting capacity. Our windows based databases are a real pain in the
> shorts, they are constantly hitting that "blue screen of death" at least
> once a week. As it is after 1 June we will no longer support or validate a
> Windows database.
> *Dick Goulet***
> Senior Oracle DBA/NA Team Lead
> PAREXEL International
> ------------------------------
> *From:* [mailto:
>] *On Behalf Of *Mohammad Rafiq
> *Sent:* Monday, February 22, 2010 8:50 PM
> *To:* Robert Freeman; oracle list
> *Subject:* RE: Oracle RAC on Win vs. Oracle on Linux
> Robert,
> I don't agree that Window is evil. I seen problems with Windows NT (mostly
> memory leak related) but after handling Oracle databases on Windows 2000 or
> newer version, it is quite stable. However it depends on SA of Windows
> server how competent they are to configure and handle Windows server.
> I am mostly supporting Oracle databases of various versions on HP, RedHat
> Linux and Windows and did not find serious issues with Windows 2000+
> servers. Although it is not a preferred environment but due vendor
> requirements for their application (specially for pharmceutical industry
> which needs validated application/databases) we need to put Oracle databases
> on Windows 2000/2003 servers.
> Regards
> Rafiq
> ------------------------------
> Date: Mon, 22 Feb 2010 15:05:10 -0800
> From:
> Subject: Oracle RAC on Win vs. Oracle on Linux
> To:
> Anyone want to jump in on their preferred platform for RAC? Personally I
> tend to lean towards Linux for stability purposes, but I'd like your
> thoughts on why you prefer either platform for RAC. Specifically why would
> you avoid windows (other than the fact that it's evil), or would you?
> RF
> Robert G. Freeman
> Master Principle Consultant, Oracle Corporation
> Oracle ACE
> Author:
> Oracle Database 11g RMAN Backup and Recovery (Oracle Press) - ON ITS WAY
> OCP: Oracle Database 11g Administrator Certified Professional Study Guide
> (Sybex)
> Oracle Database 11g New Features (Oracle Press)
> Oracle Database 10g New Features (Oracle Press)
> Other various titles
> Blog:
> ------------------------------
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Niall Litchfield
Oracle DBA

Received on Tue Feb 23 2010 - 03:11:30 CST

Original text of this message