Re:The Sad Reality of Post-Mature Optimization
by joe_the_user on Saturday August 13, 2011 @11:00PM
(#2882654)
...In an established code base that is reasonably well designed and well written, the performance is rarely dominated by a small number of very expensive bottlenecks that are ripe for local optimisation. Such things have usually been worked out a long time ago and there is no low hanging fruit left to pick.
Uh yeah. But I think this discussion is about creating a code and when to optimize it. It is kind of a tautology that when the code has been optimized and low-hanging fruit have been picked, they are, uh, gone.
Re:The Sad Reality of Post-Mature Optimization
by Silhouette on Sunday August 14, 2011 @02:56AM
(#2882993)
Sure, but if you get to "just before shipping" then hopefully you are already well past that point. As the article said, you typically can't just retrofit more performance at that stage without some serious rewriting.
Unfortunately, I don't think that is usually what happens. In an established code base that is reasonably well designed and well written, the performance is rarely dominated by a small number of very expensive bottlenecks that are ripe for local optimisation. Such things have usually been worked out a long time ago and there is no low hanging fruit left to pick.
At that point, if you've got five layers of architecture and each is only running at 75% efficiency because of all the little details, that might take your overall performance down to perhaps 25% of what it could be. If your software is I/O bound anyway or runs in half a second, you might not care. If that is the difference between taking a week to complete your research calculations and taking a month, or it represents a 5x increase in your hardware budget, then you probably care very much.