Re: Oracle on Windows vs Solaris or Linux ?

From: Michael Austin <>
Date: Mon, 10 Mar 2008 01:56:06 GMT
Message-ID: <Wy0Bj.22571$>

Yong Huang wrote:
> On Mar 9, 4:45 pm, Michael Austin <> wrote:

>> Do not enable HYPER-THREADING on the Windows box.  I have had more than
>> one db performance increase significantly by DISABLING it - Oracle does
>> not HT very well on Windows.  On one app, the db functions went from
>> 400ms to 10ms by disabling HT.

> Hi Michael,
> Do you happen to know exactly what had caused the problem? Is there an
> Oracle or Microsoft bug? Did you try explicitly setting cpu_count=1
> without disabling hyperthreading at OS level? If that works, you can
> unset it and try other parameters to narrow down,
> _kgl_latch_count=0, ..., any parameter that changed value when you set
> cpu_count=1. By no means am I saying these are better workarounds. But
> if you follow this process, you *might* find the real cause.
> Yong Huang

I am no longer at that site (almost 2 yrs ago...) The system was a single-processor - single core or dual core (tried both) with HT turned on that we noticed having the issue. Received on Sun Mar 09 2008 - 20:56:06 CDT

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