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Is there some science going on that tells us lousy developers what users expect from an enterprise desktop-application in terms of application startup time?
My application uses a splashscreen that informs the user of the applications current loading-state; however it still needs roughly 30 seconds (on my dev machine) to 1 minute (on a C2D 4 GB) machine to start up.
What do the users expect?
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The science will tell you to take all the different variables into effect. There are not many variables given in your description.
Is it a critical application? Who is using the application and are they aware of the complexity involved? Is the majority of the group on hardware that supports an optimal use of the application? When the application finally has start up, does it respond well etc? Does it deal with hibernate/sleep modes nicely so it doesn't require to start-up each working day.
My fist thoughts about a slow start of the application is, that much happens on the machine to get things ready (much I/O action etc) and I will have some idea of its complexity and except/accept certain waiting times. If not, I assume it is badly written or it's doing something else then what it suppose to do ("can I trust the software publisher?").
Either way, I am sure there is research what users find acceptable waiting times but is that helping you what you are looking for? Because, if you know that number, can you speed up to process?
You may consider two modes of operation: "lite" and "full". The Lite mode would be all the basic functionality. Consider such situation: I'm leaving the office for business trip, I'm in hurry and I realize I forgot to print one more drawing I should present to my client. So I run the computer (it's some minutes), then I open some CAD editor and I just want to print a single page and then close. This basic (or lite) mode could only give some core functions, let's say opening files that are read-only, so I don't need to wait to open all 3d-libraries, millions of fonts etc.
But I can also, for normal work day, start full mode application.
And by the way, please do not use for "full mode" something like "expert mode", "professional mode" etc. This makes me afraid that I'm not that expert and by touching something I can break it. "Full" mode can also be not applicable if it can be related to a shareware that for full mode you have to pay something. Perhaps "basic" and "normal" would be better.
And heading back to your question: this technique with splash screen showing the progress of running is good, but I always wish the splash screen is not "always on top" and it has minimize button and when the application finishes loading it doesn't receive focus, because during the start-up I may want to type something in a text processor and if I don't look at the screen I may not realize that I'm typing the text to another application.
