RE: EM12c false alarms for blocking locks

From: Peter Sharman <>
Date: Fri, 31 Aug 2012 21:48:25 -0700 (PDT)
Message-ID: <78a6c9d8-fde0-4510-bac4-ad59021ed54a_at_default>

Hey Rich, sorry for the delay in responding, Kellyn's been keeping me busy writing the architecture chapter for our book. ;)

Are you still having issues with the blocking locks and CPU wait spikes you've mentioned on the list in the past week or two? I might have a minute or two to look into it before life gets crazy again, this time with my eldest daughter's 21st!


Pete Sharman
Principal Product Manager
Enterprise Manager Product Suite
33 Benson Crescent CALWELL ACT 2905 AUSTRALIA Phone: +61262924095 | | Fax: +61262925183 | | Mobile: +61414443449 

"Controlling developers is like herding cats."
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Bruce Pihlamae, long term Oracle DBA

-----Original Message-----
From: Rich Jesse [] Sent: Monday, 20 August 2012 11:24 PM
To: Oracle L
Subject: EM12c false alarms for blocking locks

Hey all,

Lately EM12c has been alarming me with false alarms on the Blocking Session Count metric. It's collecting the metric every minute and even though I keep cranking up the "Number of Occurrences" value from 1, 2, 3, and 5, it still keeps alarming a few times per day (and night!).

The target DB has never had a locking issue. And when I investigate the new block, it's gone. The offending processes are everything from LGWR, PQs, and regular user sessions. It seems like it's alarming for some "benign" lock (e.g. shared) and ignoring the number of occurrences. It's also only started since I installed the BP1 EM12c patch, although not immediately after the install. I just upgraded the target DB from to (yay!), and there's no change in the pattern.

Anyone else seeing this? I've got too many SRs open already... :)

TIA! Rich


Received on Fri Aug 31 2012 - 23:48:25 CDT

Original text of this message