Do Small Memory Leaks Matter Anymore?

Question

With RAM typically in the Gigabytes on all PC\'s now, should I be spending time hunting down all the small (non-growing) memory leaks that may be in my program? I\'m talking abo

Answer 1

A memory leak really depends on several things:

• How often the leak happens
• How much memory is lost each time
• How long is the program going to run

For example, if you lose 40 bytes every time a task happens, and that task happens when the program starts, then nobody cares. If you lose 40Mb every time the program starts, then it should be investigated. If you lose 40 bytes every frame in your video or game engine, then you should look into that, because you'll lose 1.2kB each second, and after an hour you would have lost almost 4Mb.

It also depends on how long the program is going to stick around for. For example, I have a small calculator app, that I open, run a calculation in, and then close again. If that app loses 4Mb in it's run, then it doesn't really matter, because the OS will reclaim that lost memory once I close it. If the hypothetical video/game engine mentioned earlier lost 4Mb an hour, and it ran a demo unit, for several hours a day at a stand at a convention, then I'd look into it.

An example of a famous memory leak is Firefox, which lost a lot of memory in it's earlier versions. If your browser leaked memory 10 years ago, then you probably wouldn't care. You shut down the computer every day, and you while running the browser you only had one page up at a time. Today I just let my laptop go to standby, and I never close Firefox. It is open for weeks at a time, and I have at least 10 tabs open at any given time. If memory leaks every time a tab is closed, then that is going to build up to a larger leak now than it did 10 years ago, and so it is more important.