A quick collation – and warning – for 11.2
- MOS (Metalink): Bug 9842771 – Wrong SREADTIM and MREADTIM statistics in AUX_STATS$ [ID 9842771.8] (needs MOS account)
- Comment from Sokrates in a Charles Hooper blog
- Blog item by Christian Antognini
- Blog item by Randolf Geist
Bottom line – be careful about what you do with system stats on 11.2
Footnote: the MOS link is a search string producing a list of references. I set it up like that because one of the articles referencing the bug is called “Things to consider before upgrade to 11.2.0.2” and it’s worth reading.
Addendum: one of the people on the two-day course I’ve just run in Berlin sent me a link for a quick note on how to set your own values for the system stats if you hit this bug. It’s actually quite a reasonable thing to do whether or not you hit the bug given the way that gathering the stats can produce unsuitable figures anyway: setting system stats. (I’ve also added their company blog to the links on the right, they have a number interesting items and post fairly regularly.)
Thanks Jonathan! I was writing about this on CDOS recently, as a matter of fact, the debate was about the bug mentioned in your post.
Comment by Mladen Gogala — September 12, 2011 @ 10:35 pm BST Sep 12,2011 |
Mladen,
It was your post that prompted me to collate a few notes I’d seen on the topic.
I’ve just added a link to another note that points out that you can always fake the system stats anyway – which I prefer to do rather than gathering them anyway.
Comment by Jonathan Lewis — September 16, 2011 @ 8:33 am BST Sep 16,2011 |