Oracle VM Consulting
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Do you like to watch TV? Watch Enkitec.TV from now on! :-)

I’m happy to announce Enkitec TV which is a video channel/aggregator of some of the coolest stuff we do here at Enkitec.

Future Appearances 2012

Here’s the list of public events where I’ll be speaking this year:

Enkitec’s Extreme Exadata Expo in Dallas, TX (13-14. August 2012):

Additionally I’m going to be around to participate at Q&A sessions, panels, random Exadata hacking and just for fun! :)

 

The limitations of CURSOR_SHARING = FORCE and FORCE_MATCHING_SIGNATURE for SQL plan stability

It’s a well known fact that the cursor_sharing parameter can be set to FORCE for making Oracle replace any literals with system-generated bind variable placeholders and then calculating the SQL hash value for looking up an existing cursor in library cache. This should reduce the amount of hard parsing and shared pool garbage.

Enkitec Extreme Exadata Expo (E4)

Enkitec recently completed its 80th Exadata implementation, so this is a good time to announce that we are organizing the first Enkitec Extreme Exadata Expo (E4) on 13-14.

MOATS-like sqlplus “top” utility for RAC

 

So, you think MOATS was cool?! Check this out by Jagjeet Singh :)

 
 
 

Oradebug hanganalyze with a prelim connection and “ERROR: Can not perform hang analysis dump without a process state object and a session state object.”

Back in the (really) old days, systemstate dumps had to be used for diagnosing hangs and finding blockers of hung databases. Basically you just identified which resource your waiting sessions were waiting for and then scanned through the rest of the system state dump to see which session held that particular resource (note that over time the instrumentation and systemstate dumps have evolved to resolve and dump the blocker information right at the waiting session section in the dump).

Advanced Oracle Troubleshooting Guide – Part 10: Index unique scan doing multiblock reads?!

When you troubleshoot an Oracle (performance) problem you usually want to find out what are the problem sessions doing (wrong) and then why are they doing it.

The “what” question is usually answered using some wait interface based method – like ASH or SQL*Trace, which both add plenty of extra details to the plain wait event data.

My normal session troubleshooting data collection sequence consists of only three steps:

Broken links fixed :-)

Ok, it took only a year or so, but I’ve fixed most of the broken links (to my scripts etc) in my blog :-)

Please let me know if you hit any more broken links from now on….

Where is LOB data stored?

There was a question in Oracle-L about where is the LOB data actually stored (in the row or the LOB segments) and what are the exact conditions when a switch from one to another may happen.

Asynchronous I/O for people

Ok, I’ve wanted to write this blog entry for a long time – and now it’s time!

Most of my blog readers (thank you!) are performance-minded computer enthusiasts, who care about efficiency and optimization. You’ve been tuning SQL execution plans, instance and OS configuration so that your sessions would achieve the same results with less work and also with less waiting!

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