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November 2013

Drill Down the I/O stack at UKOUG Tech13

It’s just under a week to go before the doors open for the UKOUG Tech13 conference and the adjoining OakTable World UK 2013 sessions, so I thought I would write a very short blog post about what I will be doing there, where I’ll be, and what I’m looking forward to. This year I will … Continue reading "Drill Down the I/O stack at UKOUG Tech13"

Drill Down the I/O stack at UKOUG Tech13

It’s just under a week to go before the doors open for the UKOUG Tech13 conference and the adjoining OakTable World UK 2013 sessions, so I thought I would write a very short blog post about what I will be doing there, where I’ll be, and what I’m looking forward to. This year I will … Continue reading "Drill Down the I/O stack at UKOUG Tech13"

OTNYathra 2014 : India OTN Tour

Just a quick note to say the top-level approval for OTNYathra 2014 – India OTN Tour has been granted. Next, we’ve got to submit our individual travel approvals and see how that goes. If everything goes to plan, I will be representing the Oracle ACE Program on this tour in February, which visits the following locations.

  • Jallandar – 18th February
  • Delhi - 20th February
  • Mumbai - 22nd February
  • Pune - 23rd February
  • Hyderabad - 25th February
  • Bangalore - 27th February
  • Chennai – 1st March

Fingers crossed everything goes to plan. :)

Cheers

Tim…

12c Adaptive Optimization – Part 1

Last week I did a webinar on 12c Adaptive Optimization. The talk was recorded. The slides are here: 12c Adaptive Optimization V2 PDF. The recording can be found here: 12c Adaptive Optimization Recording. There were a number of follow up questions and emails so I thought I’d summarize here. Since there were so many questions, (I guess I must not have done that good of a job of explaining how it works) I will break them up into 2 or 3 posts. So for this first one I will just cut and paste from a couple of email follow ups.

Here’s the first question(s):

Hi Kerry,

When the Oracle wait interface isn’t enough

Oracle has done a great job with the wait interface. It has given us the opportunity to profile the time spend in Oracle processes, by keeping track of CPU time and waits (which is time spend not running on CPU). With every new version Oracle has enhanced the wait interface, by making the waits more detailed. Tuning typically means trying to get rid of waits as much as possible.

Tech13 Agenda

It’s coming up to the time when I have to think about which presentations to go to at UKOUG Tech13 – always difficult to decide whether to see topics I’m familiar with to find out how much I didn’t know, or whether to see topics which I don’t know to get some sort of intelligent briefing. Here’s my starting thought:

Super Sunday:
12:30 Me, on compression (index, basic and OLTP – not HCC)
13:40 Tony Hasler: “Why does the optimizer sometimes get the plan wrong”
15:00 Kyle Hailey: “Oracle transaction locks and analysis”
16:00 Neil Chandler: “10046 trace – powerful, or pointless in the real world”

Once you’ve done your I/O…there’s still more to do !

The world is obsessed with I/O nowadays….

This is understandable – we’re in the middle of a pioneering period for I/O – flash, SSD, MLC, SLC, with ever more sophisticated transport mechanisms – infiniband, and the like.

But don’t forget, that once you get those blocks back to Oracle, you need to “consume” them, ie, get those rows and get that data…

And that’s not free !

For example, lets look at two tables, both 500 megabytes, so the I/O cost to consume them is thereabouts the same.

The first one has ~50byte rows.

Top 100 Books Of All Time (I Can’t Read)

And now for something completely different. David Bowie recently revealed a list of his top 100 books. It was a really interesting list, especially considering that being such a huge David Bowie fan for so many years, I had only actually read 2 of the books on his list (“Nineteen Eighty-Four” by George Orwell and […]

Locked Forums

Just a quick note to say I’ve had to temporarily lock my forums. As happens every so often, the spammers are hitting it pretty hard at the moment. I’m a bit sick of spending every waking minute deleting hundreds of spam posts, so I’m giving myself a break for a while. During previous episodes, after a couple of days of no joy it’s died down, so hopefully it won’t last too long this time either…

Cheers

Tim…

Update: It’s late and I’m tired. I just remembered I can prevent new registrations, so I’ve unlocked the forums, but stopped all new registrations. That way, existing members can carry on as normal… :)

EM12c- Managing Incidents, Stopping the Insanity, Part I

As many folks know, “white noise” or having incident alerts that don’t offer value is something that I just refuse to tolerate.

The metric alert “Listener response to a TNS ping is xxxx msecs” is valuable, as it represents how many milliseconds it takes the listener to respond to a network request, (i.e. ping).