Comments on: Making sense of ASH TIME_WAITED Units

By: MVE

MVE — Tue, 02 Feb 2010 19:17:38 +0000

@Roger,

I think it’s just the way the author represented the test case in this document, it wasn’t meant as the UOM definition:

By: Roger Baker

Roger Baker — Tue, 02 Feb 2010 17:00:11 +0000

You mention at the top of the article that it is believed TIME_WAITED is presented in microseconds. However the Graham Wood article that you reference, http://www.oracle.com/technology/products/manageability/database/pdf/twp03/PPT_active_session_history.pdf indicates on page 35 that the units are “ms” which is milliseconds. I realize whatever it is, it is an approximation, but why cant Oracle just tell us what it is in their documentation?

By: Blogroll Report 31/07/2009 – 07/08/2009 « Coskan’s Approach to Oracle

Blogroll Report 31/07/2009 – 07/08/2009 « Coskan’s Approach to Oracle — Wed, 12 Aug 2009 14:32:31 +0000

[...] Vitaliy Mogilevskiy- Making sense of ASH TIME_WAITED Units [...]

By: MVE

MVE — Tue, 11 Aug 2009 02:43:48 +0000

Thanks Karl! I am going through the PPPs and the AAS (Average Active Sessions) approach to looking at system overload makes sense to me — good stuff

By: Karl Arao

Karl Arao — Thu, 06 Aug 2009 11:47:47 +0000

Yes I agree
ASH data is a statistical approximation.. Not exact, but close enough to be used.. that’s why we do count(*) because each sample is 1second. You can know more from the seminar slides of Kyle Hailey. The first 9 slides tackled more on ASH..

http://www.perfvision.com/ftp/emea/

- Karl Arao