Re: Performance Question

Is the query definitely taking the same access path, and using exactly the same amount of logical I/O, and is the latching identical ?

Is this is an otherwise silent system so that no other concurrent processes could be having an undue effect on the query ?

For benchmarking purposes, there is a script on my web site under Miscellanrous -> Myths which generates a huge amount of logical I/O against one buffer block using simple acces mechanisms. I have usually found that Windows systems operate at about half the effective CPU of UNIX systems, so your result is a little surprising. You might like to download the script and see what happens on your two systems. (You might like to download the 'performance snapshot' package - or use statspack - to find out if there is any significantly different latch activity between the two versions, particularly on the cache buffers chains latch). Note that there is a bug which I think arrived in 8.1.7 and is fixed in 8.1.7.3 that increases the latch activity on root blocks of indexes - the nature of the bug is such that it could be sufficient to cause the effect you are seeing.

--
Jonathan Lewis
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gdas wrote in message <7a4ed455.0203301819.45eadc67_at_posting.google.com>...


>Hi,

>

>I recently moved a database running Oracle 8.1.6 from Windows 2000 to

>Oracle 8.1.7 on Solaris 8.  This was part of a hardware upgrade that

>was intended to improve performance and scaleability.  I'm currently

>running both systems for performance comparisions right now.

>