Re: Excessive Logical IOs against which Table/Index
From: Mladen Gogala <gogala.mladen_at_gmail.com>
Date: Tue, 26 Apr 2016 07:51:53 -0400
Message-ID: <571F5659.3010807_at_gmail.com>
On 04/25/2016 01:44 PM, Stefan Koehler wrote:
> 1) SQL Monitoring Report (needs additional license)
> 2) DTrace for Solaris:https://alexanderanokhin.wordpress.com/2011/11/13/dynamic-tracing-of-oracle-logical-io/
> 3) SystemTap for Linux:https://db-blog.web.cern.ch/blog/luca-canali/2014-12-life-oracle-io-tracing-logical-and-physical-io-systemtap
Whoa! DTrace and systemtap? What has happened to the good old 10046 trace? I can wholeheartedly recommend an ancient book called "Optimizing Oracle for Performance" by Cary Millsap and Jeff Holt. That book describes the tuning methodology, in detail. I find systemtap information less than useful. The OS tracing tools intercept system calls and can summarize what types of calls were made and what were the arguments, as well as which routine has made the call. Unless there is a very good knowledge of Oracle source and naming scheme, the result is pretty much meaningless.
I am still sticking to the method developed by Cary and Jeff, as it is a still unsurpassed tuning methodology. Admittedly, their book is a bit old, written for the version 8i, but still equally as relevant as it was on the day it was released.
Date: Tue, 26 Apr 2016 07:51:53 -0400
Message-ID: <571F5659.3010807_at_gmail.com>
On 04/25/2016 01:44 PM, Stefan Koehler wrote:
> 1) SQL Monitoring Report (needs additional license)
> 2) DTrace for Solaris:https://alexanderanokhin.wordpress.com/2011/11/13/dynamic-tracing-of-oracle-logical-io/
> 3) SystemTap for Linux:https://db-blog.web.cern.ch/blog/luca-canali/2014-12-life-oracle-io-tracing-logical-and-physical-io-systemtap
Whoa! DTrace and systemtap? What has happened to the good old 10046 trace? I can wholeheartedly recommend an ancient book called "Optimizing Oracle for Performance" by Cary Millsap and Jeff Holt. That book describes the tuning methodology, in detail. I find systemtap information less than useful. The OS tracing tools intercept system calls and can summarize what types of calls were made and what were the arguments, as well as which routine has made the call. Unless there is a very good knowledge of Oracle source and naming scheme, the result is pretty much meaningless.
I am still sticking to the method developed by Cary and Jeff, as it is a still unsurpassed tuning methodology. Admittedly, their book is a bit old, written for the version 8i, but still equally as relevant as it was on the day it was released.
-- Mladen Gogala Oracle DBA http://mgogala.freehostia.com -- http://www.freelists.org/webpage/oracle-lReceived on Tue Apr 26 2016 - 13:51:53 CEST