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There she goes, squirreling into the corner of your carry-on.  Ready for another adventure.  Tucked between a fun floppy hat and the flourescent sun-block, of which she uses plenty, pale creature that she is, Monique is situated to prove to you that a seasoned traveller knows best.  Dressed in a curly mohair (so as not to show the wrinkles that betray one new to the jet set) and sporting a pale chiffon scarf – to double as a disquise in those cities where she is already known for her somewhat silly escapades – she seems to wink at you and beckon you along.  Forget your cares, but by no means your playing cards, and step lightly into whatever dreams your next voyage should hold for you:  let Monique be your guide.  

Her very presence alleviates all the maladies brought on by the jostling of trains, the dipping of ships, the swerving of buses and even by the simple fact that you are far from home.  For she has discovered the secret to successful travel; with the exception of the luscious few minutes in the X-ray machine, where she delights in making funny faces at the operators searching for more dangerous contents.  Monique never looks back.

Charleen Kinser Designs

(With thanks to Carol Dacko for bringing along an interesting dinner companion for my own cuddly friends. Somehow I doubt they’ll ever be the same – she’s terribly sophisticated for my lot!)

Hotsos 2010 – Day 4

First up was Cary Millsap’s – Lessons Learned, Version 2010.03 As Cary pointed out, they always try to put the best speakers in the toughest slots – 8:30 in the morning post-party. I think local guys are slightly more reliable too because they might have actually gone home the night before! He started with a quick Hangover Survey (me – check!) and then pressed on talking about how we test system performance.

He showed a video of Boeing stress-testing the wing of the 787 and, as he pointed out, aircraft manufacturers really know how to stress-test! (Of course whether that reassures you as it does me, or makes you wish no-one would talk about wings disintegrating, as it probably would Mads, is personal.) They showed Boeing test equpiment which is complicated, expensive and non-revenue generating. Those tests are expensive but when people’s lives are on the line, what choice is there? Boeing knows that it has to test the analytic models used in the design. He spent a lot of time talking about good test design. A few thoughts that stood out to me …

- Some stress tests are a waste of time. Will the Boeing 787 land on the moon? If this test fails, what has it proven? If it passes, then it’s awesome but it would be a very expensive way to prove it can cope with commercial flights in Earth’s atmosphere.

- Why test for more than you will see in Production? Because you don’t really know for sure what you’ll see in Production.

- At some point, but I can’t remember the context, he used a Scottish phrase that he’d heard Billy Connolly shout (although the Big Yin was only fully credited later in the day) …

    "There’s no such thing as bad weather, just the wrong clothes"

… looked over at me and said – "I’d love to hear you say that, with the proper accent". I declined politely.

- Most people try to prove only that their systems will work.

- Most tests of systems that are destined to fail never proved it in advance.

- Test to destruction

    a) Test
    b) Until the system melts
    c) Decide whether your real requirements are likely to be lower or higher than melting point.

There was a small amount of time for questions and once it looked like they were done, I granted Cary’s wish (never thought I’d say that), stuck my hand up and repeated The Big Yin’s words. It was only after the laughter had stopped that I realised I might have ruined his big closing, but I think he was ok about it

Next was Tanel Poder talking about LGWR, log file sync waits and COMMIT performance and shock, horror, I was actually going to say that this was one of the least rewarding sessions of the week for me. What?!? Tanel? But he’s, like, an Oracle God! LOL But there were reasons

- I realise that I know a *lot* about how log file sync and log file parallel write work, how they relate to each other and some of the problems they might help you identify. Because it’s a subject I’m *so* familiar with, I didn’t learn much.

- His main demo didn’t quite show what he wanted it to because it didn’t run multiple sessions but, frankly, I’m in no position to talk about demos this week!

By the end, the presentation turned out ok, not least because there was another unexpected appearance from Bob Sneed to talk about the I/O components involved in  redo log management including a suggestion that LGWR be put into a higher scheduling class (but not Real Time!) I’ll try to find a link to his slides and let you take a look yourself.

I loved Tanel’s Big Log File Sync Tuning Secret, though …

    COMMIT LESS!

It was particularly relevant to me because I had a Big Log File Sync Tuning Secret as the closing moment of my own presentation. The problem was I couldn’t use it after the demos went wrong!

    USE ASYNCHRONOUS COMMITS

But, in my case, that was supposed to be funny, too.

I ran off to try and use the free breakfast voucher that Marco had given me but I was just too late. No food again, then Well, I had a couple of slices of cold meat at lunchtime, but mainly to catch up with Alex G before he had to present and then head back to Ottawa. I managed to skip one session at this stage but, after a quick call home, I decided to go along to Alex’s RAC Connection Management presentation after all (a little late). Although I have seen some of this stuff before, I always enjoy watching Alex’s demos and was particularly impressed by the fact that he’d managed to write his own RAC connection load balancer! I was waiting for the applause in the room but either people didn’t quite get it or there was just a lack of energy post-lunch on the last day. I suspect the latter.

Of course, once I’d said goodbye to Alex properly (don’t see him nearly enough), I was a little late for whichever session was going to be my final one of the conference and I was hopelessly torn between Kyle Hailey’s modern SQL performance tools presentation (Kyle’s done a lot of cool work in the area of Oracle Performance Visualisation) and Chris Antognini’s Diagnosing Parallel Executions Performance. In the end I plumped for the latter because I thought it was going to be like something I’d unsuccessfully attempted a couple of years ago and I wanted to see if Chris had a different angle on it and had been more successful. In the end, I probably made the wrong choice because although Chris’ presentation was great, it was really all stuff I already knew. Definitely my bad call, though. Hopefully I’ll get a chance to catch up with Kyle’s presentation at some point in the future too!

After that there was just the usual short farewell and thanks from Gary Goodman of Hotsos. Although the thanks were appreciated, I’m glad they were spread around everybody because the attendees are one of the things that make this conference great and Becky and Rhonda did their usual sterling job of organising everything.

Then it was time for some Fajitas with a few friends (actually, a whopping great number of friends who practically filled the Mexican restaurant!) and a few very sedate beers. (We are old men (and women) now and the night before had a big one!) While we were waiting to go to the Mexican, I had one great surprise left – Alex’s flights weren’t going to get him home, so he came back from the airport and had to check in overnight! At least I got a chance to talk to him properly when I wasn’t hopelessly drunk and didn’t try to seduce him this time.

Now I need to stop blogging and get back to listening to Tanel’s Training Day (good stuff, too, but more about that later)

In the end my work call fell through so I had the unexpected opportunity to see Marco Gralike’s XML presentation. Despite the fact that he was scheduled opposite Tanel Poder talking about performance fundamentals, which impacted the number of attendees, I thought it was terrific. I had my own brief flirtation with XML around 10 years ago but, contrary to my expectations, there was lots for me to learn here and it was interesting to see how much more mature Oracle’s offering is these days. I suppose 10 years is a long time, but a lot has happened while my back was turned.

The slides were excellent, the pace was good (although he did run over a little) and I could actually understand what he was saying for a change I walked away very impressed and when I was talking to a couple of his attendees at the bar later, it seems I wasn’t the only one.

Another unexpected bonus was that Henry Poras had to cancel for personal reasons and although I was extremely disappointed by that because we share interests, replacements don’t come much better than former Sun luminary Bob Sneed, who is now an independent consultant, available for hire.

His presentation was about one of his favourite topics, CPU Quality of Service. Rather than just measuring how much CPU is available or being used, we need to drill down into how it is being used. Even a 100% busy system does have available CPU really when you think about it, because if we could make our application more efficient, that would release CPU or perhaps we’re exceeding our SLAs and could reduce CPU consumption and still reach our SLA targets?

But, most of all, it’s about the quality of the resource delivered to applications that need it. He walked through a number of case studies of 4x to 16x system performance improvements, some as simple as changing scheduling strategies and some down to bug fixes or application architecture tweaks to improve Cycles Per Instruction (CPI) figures. Chip architectures seem complex these days so although the O/S thinks the CPU is busy, who knows what it’s busy doing?

My final presentation of the day was Kerry Osborne’s Scripts. I enjoyed his presentation as much as I enjoy his blog posts. He’s a very down-to-earth and modest guy but clearly has shed-loads of practical experience and a great way of communicating it. He was bothered a little by a slightly slow network connection but, frankly, I don’t know what he was whining about. That man has no idea what a demo problem is! I really liked his attitude towards his scripts, too – take them, use and abuse them, knock yourself out! Well, his scripts have helped me many times over the past year. A good guy.

After that, I was just about ready for a beer so adjourned to the bar with Marco hoping to catch up with Kerry and buy him a beer I’d promised him. It was 4:30 at this stage and I lazily decided to skip the last session. The usual daily tiredness was starting to kick in which wasn’t helping but, in retrospect, curing it with alcohol probably wasn’t the smartest strategy! Carol Dacko and Kevin Closson showed up and it was good to get another chat with them because I don’t get to see either of them often. Kerry turned up eventually and, although I may have bought him that promised drink, I’d have to admit that he did all the leg-work by going to the bar and bringing a large round of drinks back. Saved me a trip

Slowly it began to dawn on me that my planned trip back to my room to freshen up and change before the party was in jeapordy as the clock ticked around until 7:30 and I noticed Kyle Hailey’s other half unbuttoning his shirt to the navel in preparation for Disco Night.  (Check the start time above – 3 hours drinking *before* the party and,
as usual, no food.) It’s little wonder that I was quite as drunk as I was, unusually so, believe me. Although I think I just about managed to behave myself, it was a close-run thing. As I pointed out to Alex and Marco, you always know when a Scotsman is truly drunk because he starts declaring  his undying love for all and sundry. I think at one point I was actually trying to seduce Alex, but he was having none of it! Oh, my god, I think I was dancing for a few minutes!

Time to draw a discrete veil over the day, I reckon.