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    <blockquote> <p>Autorelease is not normally the wrong thing to do... I thought it's really memory intensive, so it should naturally be the wrong thing to do.</p> </blockquote> <p>It's not "memory intensive" at all. If you allocate and autorelease a very large number of objects, such as in a loop, or a smaller number of large objects, you could run into problems. But autorelease just delays the release of objects that you're creating anyway, and which may or may not even be deallocated when the release does happen (the autoreleased objects may also be retained by other objects).</p> <p>If you can release an object immediately, do that. If you need to autorelease, then do that and don't worry about the memory. If you're creating lots of objects in each iteration of a loop, you might want to consider either using your own autorelease pool or creating said objects with alloc/init so that you can release them immediately.</p> <blockquote> <p>But as for the last sentence, I'm afraid I don't get it.</p> </blockquote> <p>If a method had to release every object that it created before returning, there'd be no way to return an object without requiring the caller to release the returned object. Autorelease allows a method to create an object and release it, but to defer that release until the caller has had a chance to use and possibly retain the returned object.</p>
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    1. COThanks. But now I am entirely confused about the memory usage of autorelease as other people have told me the exact opposite: ONLY USE IT IF YOU REALLY REALLY HAVE TO... perhaps its best to talk about hard figures. An iPhone has how much memory? 256MB? How much of that is usually used for the iOS? How much is there for my App? How much does, for example, a simple string need in terms of memory? 256 bytes? How many strings would I need to create to run into serious memory problems so that it crashes my app? ... Sorry, but I'm thoroughly confused about all of this.
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    2. CO@n.evermind you should be fine using `autorelease` unless you can *prove* that its 1) causing a *measurable* slowdown in your app or 2) causing memory to build up unnecessarily. You'll never be able to prove 1), and if 2) is a problem, you're always welcome to make your own autorelease pools.
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    3. COPerhaps you should ask the people you've given you this "only if you really have to" advice why they say that. Sounds more like superstition than good advice to me. Looking at TheElements in Instruments, I see 1017 live strings consuming about 28K of data. If you keep to that average, you'd have to create 37,000+ autoreleased strings to consume just one megabyte, and they'd all be released as soon as the autorelease pool is drained, which happens when control returns to the run loop (or when you drain your own pool).
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