Grid Control Accessibility

I work at a site that has Diagnostic and Tuning Pack licenses (yippee!) so, before we started deploying Grid Control, I tried to encourage the installation of Database Control in the mean-time so that people could get used to the Performance Pages that I find incredibly useful.

I was fascinated to see how my blind colleague Richard would get along with the pretty pictures because the big benefit to me is the at-a-glance view of things which helps me determine whether a database looks like it has a serious performance problem. (Yes, I'm aware of the heresy implicit in that statement when compared to building a response time profile for an individual session a la Method R or YAPP, but sue me - I'm still identifying performance problems successfully without that approach. Not all categories of problem, for sure, but it's useful for most things.) Then I can drill down through the data to the sessions or SQL statements of interest. However, the start of the process has become a very visual one for me.

Anyway, without wishing to speak for Richard (hint - there's a comment box below), the initial results were surprisingly good. We had previously used Quest's Foglight for monitoring which, because it is based on images, is completely useless to anyone blind. They can't see a thing. The same is true for the Oracle Universal Installer and it's time Oracle addressed that. I suspect it drives Richard slightly nuts that he can breeze through most DBA tasks with equal or greater competency than others and then has to ask people to help clicking a few buttons. 

I was worried that the Top Activity screen would be similarly useless but, because it's based on all the usual HTML stuff, it can be navigated and read using Richard's standard but still impressive approach of a blur of keyboard shortcuts and intense listening to his speech software. In fact the tables are turned, because I often can't see where the hell he is on the screen when we're going through something for the first time, so he has to tell me. I'm metaphorically blind at those moments. I'll stick to the metaphorical version if you don't mind, though. It's a deeply unsettling experience for the few moments I experience it although it can be quite funny, too. I have to ask him to maximise the browser window frequently because I can't see everything! In fact, we need to go through the whole business of getting the monitor switched on and off each time, too. At first I couldn't work out why Richard *had* a monitor, seeing that it's never switched on, but it becomes fairly essential if we *both* want to look at a problem!

So Richard can jump around that Top Activity chart and hear the time period that's higlighted, the wait classes and the proportion of activity in each of the classes. I was amazed he could do that and it's a damn site better than Foglight from Richard's perspective, but it all still seemed difficult to me. I suppose Richard has a life-time of overcoming these challenges.

However, I was still pleased when I noticed an Accessibility section of the Grid Control documentation, which contains two configuration items. The first is about switching off optimisations which might confuse speech software, but I wanted to focus on the second one here - "Providing Textual Descriptions of Enterprise Manager Charts". There are full instructions in that documentation link, so I won't repeat them here, but I will show you the example image from the documentation for those who can see it.



In fact, let me copy another welcome feature that Oracle have implemented in the documentation and paste their text description of this image for those who can't see it.

"The illustration OEM_text_link.gif shows a screen capture of a typical Enterprise Manager chart. A callout in the lower right corner of the illustration identifies the icon you can click to display a textual representation of the data in the chart. This icon appears next to all charts when textual descriptions are enabled using the procedure documented in this section of the guide."

By navigating to that little link and selecting it, it pops up a new page with a text table containing the numbers behind the chart. Much easier to read. However, one criticism I would make is that the Top Activity chart is displayed from the oldest information to the most recent. There's a certain logic to that - display the numbers as they appear on the chart from left to right, but that means that what's happened most recently is at the bottom of the table and I'm not sure that's a convenient way to read things. That's my personal view, but I'm sure others will disagree.

So, well done Oracle for thinking about this and including it.

I'd been thinking about this blog post for quite a while, but what finally prompted me to get off my back-side and write it was when one of my other colleagues, Dave, did something during the week that I hadn't thought of while we were both looking at a server performance problem. I was wondering about the sample interval of a specific chart, at which point he clicked the text table link.

[Sound of penny dropping from 10,000 feet and clanging off the top of my head.]

Of course, what an idiot I'd been. Maybe it's a very useful feature for all of us because, pretty though the pictures are, maybe I'd like to check the underlying numbers sometimes! In fact, because this is possible in Database Control, I'm going to configure it for future use when I'm teaching.

Good stuff all round and long may Oracle continue thinking about accessibility issues.

Now, about that installer ....