Tuesday, December 22, 2009

The “Do What You Love” Mirage

I am inspired by having read an article called “Do what you love mirage” by Denis Basaric. It begins...
“Do what you love” is advice I hear exclusively from financially secure people. And it rings hollow to me. When you need money to survive, you do any work that is available, love does not play into that choice. Desperation does.
Please read it before you go on.

Welcome back.

This article puts a very important cycle within my life into words. I believe, as Denis says, that a lot of times, we get the cause-effect relationship mixed up when we think about loving what we do.

I love what I do. Well, a lot of it. But Denis is right: I didn’t choose what I do out of love. I chose what I love out of doing. Some examples:
  • I love mathematics. But I most assuredly did not always love it. I learned to love it through working hard at it.
  • It’s the same thing with writing. I love it, but I didn’t always. At first, writing was unrewarding drudgery, which is how most people I meet seem to feel about it.
  • I love public speaking, but I sure didn’t love it when my speech class made me sick to my stomach three mornings a week for a whole semester my freshman year.
  • I love being an Oracle performance specialist, but I sure didn’t love being airlifted into crisis after crisis throughout the early 1990s.
I could go on. The point is, my life would be unrecognizably different if not for several really painful situations that I decided to endure with the resolve to get really good at what I hated. Until I loved it.

In retrospect, I seem to have been very lucky in many important situations. Of course, I have. But you make your own luck. Although I believe deeply in the idea of, “The harder I work, the luckier I get,” that is not what I’m talking about here. I’m talking about the power that you have to define for yourself whether something that happened was lucky for you or not. Your situations do not define your life. You create your life based on how you regard your situations.

I could have rebelled against Jimmy Harkey and hated math for the rest of my life. Lots of kids did. I could have rebelled against Lewis Parkhill and never become a writer. I could have refused Craig Newberger’s advice to take his second speech course and never become comfortable in front of an audience. I could have left Oracle in 1991 and found a job where they had more mature products....

One of the most important questions that I ever asked my wife before our engagement was this:
If you were forced to wash cars for 12 hours a day, just to make a living, could you enjoy it?
This is a “soulmate” kind of question for me. My wife’s attitude about it is, for our children and me, possibly the most valuable gift in our lives.

Loving what you do can be difficult. I think Denis hits the nail on the head by suggesting that,
By doing good work, you just might find out that what you are doing, is what you are supposed to do. And if you don’t, quality work will get you to where you want to be.
I hope you will find love in what you do today. Do it well, and it’ll definitely improve your odds.

Monday, December 21, 2009

My Whole System Is Slow. Now What?

At CMG'09 a couple of weeks ago, I presented "Measuring Response Times of Code on Oracle Systems." The paper for this presentation was a subset of "For Developers: Making Friends with the Oracle Database." In the presentation, I spent a few minutes talking about why to measure response times in Oracle, and then I spent a lot of minutes talking about how. As usual, I focused heavily on the importance of measuring response times of individual business tasks executed by individual end users.

At the end of the talk, a group of people came to the podium to ask questions (always a good sign). The first question was the question that a lot of people ask. It was:
My whole system is slow. That's all my users will tell me. So then, how do I begin to do what you're describing?
Here's the answer:
Ask your users to show you what they're doing. Just go look at it.
The results of this simple advice are routinely spectacular. Just go look at it: I'm surprised whenever someone doesn't think of doing that, but I shouldn't be. That's because I didn't do it either, for the longest time. I had to learn to. And that's the story I want to tell you here.

In the early 1990s, I was a consultant with Oracle Corporation visiting clients with performance problems at a pace of more than 30 per year. Back then, I did Oracle performance work the old fashioned way: I checked everything I knew how to check, and then I fixed everything I knew how to fix. All billable by the hour. (Note: When I was doing it this way, I had not yet been taught by Dave Ensor, who changed me forever.)

On weeks when I was lucky, I'd be finished checking and fixing by sometime Wednesday, leaving a couple of days to find out what people thought of my work. If I were lucky again (that's two "lucky"s now), everyone would be thrilled with the results. I'd get my hug (so to speak), and I'd catch my flight.

But I wasn't always lucky. Some weeks, I wouldn't find anything suspicious in my checking and fixing. Some weeks, I'd find plenty, but still not everyone would be thrilled with the work. Having people be less than thrilled with my work caused pain for me, which motivated me to figure out how to take more control of my consulting engagements, to drive luck out of the equation.

The most important thing I figured out was...
People knew before I came on-site how they were going to measure on Thursday whether they liked the results of my work.
And...
They were willing to tell me on Monday.
All I had to do was be honest, like this:
On the day I'm done working here, I'd imagine you're going to want to run something that will demonstrate whether I accomplished what you were hoping for while I was here. Would you mind telling me about that now? Maybe even showing me?
I could ask that on Monday, and people were glad to tell me. I'd watch the things run and record how long they ran, and then I'd know how to prioritize my time on site. I'd record how long they ran so at the end of my engagement, I'd be able to show very clearly what improvements I had made.

Sometimes, there would be thirty different things that people would expect to measure on Thursday. If I might not have time to fix them all, then I needed to make sure that I knew the priority of the things I was being asked to fix.

That one step alone—knowing on Monday that prioritized list of what tasks needed to be fast by Thursday—drastically reduced my reliance on luck as a success factor in my job at these sites. Knowing that list on Monday is just like when your teacher in school tells you exactly what's going to be on your next test. It allows you to focus your attention on exactly what you need to do to optimize your reward for the week. (Note to fellow education enthusiasts: Please don't interpret this paragraph as my advocating the idea that GPA should be a student's sole—or even dominant—optimization constraint.)

So, what I learned is that the very first step of any good performance optimization method is necessarily this:
1. Identify the task that's the most important to you.
When I say "task," think "program" or "click" or "batch job" if you want to. What I mean is "a useful unit of work that makes sense to the business." ...Something that a business user would show you if you just went and watched her work for a few minutes.

Then comes step two:
2. Measure its response time (R). In detail.
Why is response time so important? Because that's what's important to the person who'll be watching it run on Thursday, assessing whether she thinks you've done a good job or not. That person's going to click and then wait. Happiness will be inversely proportional to how long the wait is. That's it. That's what "performance" means at 99% of sites I've ever visited.

(If you're interested in the other 1% of sites I've visited, they're interested in throughput, which I've written about in another blog post.)

Measuring response time is vital. You must be able to measure response time if you're going to nail that test on Thursday.

The key is to understand that the term response time doesn't even have a definition except in the context of a task. You can't measure response time if you don't first decide what task you're going to measure. In other words, you cannot do step 2 before you do step 1. With Oracle, for example, you can collect ASH data (if you're licensed to use it) or even trace data for a whole bunch of Oracle processes, but you won't have a single response time until you define which tasks buried within that data are the ones you want to extract and pay attention to.

You get that by visiting a user and watching what she does.

There are lots of excuses for not watching your users. Like these...
  • "I don't know my users." I know. But you should. You'd do your job better if you did. And your users would, too.
  • "My users aren't here." I know. They're on the web. They're in Chicago and Singapore and Istanbul, buying plane tickets or baseball caps or stock shares. But if you can't watch at least a simulation of the things those users actually do with the system you help manage, then I can't imagine how you would possibly succeed at providing good performance to them.
  • "I'm supposed to be able to manage performance with my dashboard." I know. I was supposed to have a hover car by the year 2000.
The longer you stay mired in excuses like these, the longer it's going to be before you can get the benefit of my point here. Your users are running something, and whatever that is that they're running is your version of my Thursday test. You can check and fix all you want, but unless you get lucky and fix the exact tooth that's hurting, your efforts aren't going to be perceived as "helpful." Checking and fixing everything you can think of is far less efficient and effective than targeting exactly what your user needs you to target.

Lots of performance analysts (DBAs, developers, architects, sysadmins, and so on) assume that when someone says, "The whole system is slow," it means there must be a single parameter somewhere in the bowels of the system that needs adjustment, and if you can just make that adjustment, everything is going to be ok. It might mean that, but in my experience, the overwhelming majority of cases are not that way. (Pages 25–29 of Optimizing Oracle Performance has more information about this.)

The great thing about measuring response time is that no matter what the problem is, you'll see it. If the program you're watching is poorly written, you'll see it. If some other program is hogging too much of a resource that your program needs, you'll see it. If you have a bad disk controller, you'll see it. If some parameter needs adjusting, you'll see it.

Realize that when a business user says "system," she doesn't mean what you would mean if you said "system." She means that the thing she runs is slow. Look at that thing. Maybe there are seventeen of them. And sure, maybe all seventeen suffer from the same root cause. If that's the case, then fantastic, because fixing the first problem will magically fix the other sixteen, too. If it's not, then fantastic anyway, because now all of them are on your prioritized list of tasks to optimize, and you'll probably surprise yourself how quickly you'll be able to pick them all off when you focus on one task at a time.

Monday, December 7, 2009

C. J. Date: All Systems Go

Enrollment is open for the course taught by Christopher J. Date that we'll host 26–28 January in the Dallas/Fort Worth area. For many of us, this will be a once-in-a-lifetime opportunity to sit in a classroom for three days with one of the pioneers who created the field we live in each day.

I'm looking forward to this course myself. It is so easy to use Oracle in non-relational ways. But not understanding how to use SQL relationally leads to countless troubles and unnecessary complexities. Chris's focus in this course will be the discipline to use Oracle in a truly relational way, the mastery of which will make your applications faster, easier to prove, and more fun to write, maintain, and ehnance.

I'm particularly looking forward to his section about missing values—the ages-old debate about NULL—which is not covered in Chris's book upon which the course is based.

Thursday, December 3, 2009

The Thing (I Don't Like) About Video

Video is awesome. I like high-bandwidth communication. Even on the cheapest, most un-produced videos, I can see facial expressions and body language that I'd never be able to pick up from text. I can see candidness that's not going to come through in a document, even a blog that's written pretty much off the cuff. And videos with high production value, ...well of course it's awesome to watch a great short movie right at the tips of your fingers.

But...

But when you send me a 7:48 video, I have to budget 7:48 to watch it. (Well, more actually, because of the latency required to buffer it up.) When you send me a 13-page document, I can "read" it in 10 seconds if I want to. I can skim the first and final paragraphs really quickly and look for pictures or sidebars or quotes, and it takes practically no time for me to do it.

With a video, it's just more difficult to do that. I can watch the first 10 seconds and usually know whether I want to watch the remainder. But skimming through the whole video—like skipping to the end—is more difficult, because I have to sit there un-utilized while the whole video buffers up. Then I have to sit there while words come at me aurally, which is annoyingly sequential compared to reading buckets of text in one eyeful.

So, the bottom line is that the first 10 seconds of your video need to convince me to watch the remainder.

Or I won't.

Is it just me?

What's out there to make video browsing a better, more time-efficient, and more fulfilling experience?