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Improving Perceived Performance

Ah yes, perceived performance: it can be such an underrated thing. I thought Regex Hero was still loading a little slow for a ~50KB application.

In fact I looked at this a couple months ago and found that my initialization code was preventing the Regex Hero UI from appearing until it was done. As such, you'd actually be looking at a blank screen a little longer than you should.

When talking about perceived performance, a blank screen like this is just about the worst user experience possible because in the back of the user's mind they might be thinking, "Did this application just hang?" Even if they don't think that, any kind of prolonged stillness can be perceived as slowness and that's the last thing I want. So at the time I tried a few things to correct this but couldn't find a good solution that worked well and didn't cause any other problems.

Today I took another crack at it and finally solved the problem. You'll notice now that when it loads you'll briefly see the default Silverlight loading animation as you always have. And then where you'd normally see a blank screen, you'll instead see this loading box on top of the Regex Hero app for about half a second.

To be sure I actually made some progress with this I made some crude measurements. I measured the load time until you actually see the Regex Hero UI with the old method vs the time until you see the new loading box in the new method. After multiple tests and averaging the results here's what I came up with:

Before: 1.6 seconds
1.1 seconds

(Note that this test was done with a cached copy to take bandwidth variances out of the equation.)

All that work for half a second of improved "perceived" performance may seem like a waste of time. After all, the time it takes before you're able to actually use Regex Hero hasn't changed. It's still going to be around 2 or 3 seconds on the first load and about 1.6 seconds once it's cached (actual mileage may vary).

But in my mind, seeing a glimpse of the Regex Hero UI half a second sooner is huge. I think when you work with applications that load quickly and respond immediately to your input, people tend to take notice. And from the beginning this app was intended to save time when working with regular expressions so performance will always be a priority for me.

You can see the speed now by checking out the Regex Hero Tester. Don't blink. ;)


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