Re: CBC Latch contention in 10g
- From: "Jonathan Lewis" <jonathan@xxxxxxxxxxxxxxxxxx>
- To: "'Oracle-L (E-mail)'" <oracle-l@xxxxxxxxxxxxx>
- Date: Thu, 21 Oct 2004 14:00:51 +0100
It's CPU dependent. The older CPU's did not
have an atomic CAS (compare and swap)
instruction. In some cases this left Oracle using
exclusive latches, in others Oracle worked around
the problem by using a latch to emulate CAS...
the 'cas latch' - which was subsequently joined
by the 'rm cas latch'. You'd have to have a 3 or 4
year old CPU for this to be a problem though.
Regards
Jonathan Lewis
http://www.jlcomp.demon.co.uk/faq/ind_faq.html
The Co-operative Oracle Users' FAQ
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----- Original Message -----
From: "Cary Millsap" <cary.millsap@xxxxxxxxxx>
To: "'Oracle-L (E-mail)'" <oracle-l@xxxxxxxxxxxxx>
Sent: Tuesday, October 19, 2004 9:41 PM
Subject: RE: CBC Latch contention in 10g
I believe Steve Adams once told me that the shareable latch feature is =
not
implemented on HP-UX.
Cary Millsap
Hotsos Enterprises, Ltd.
http://www.hotsos.com
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