Comments on: Beware of Getters and Setters http://jacksondunstan.com/articles/433 Mastering AS3 Tue, 07 Feb 2012 09:30:08 +0000 hourly 1 http://wordpress.org/?v=3.3.1 By: jackson http://jacksondunstan.com/articles/433/comment-page-1#comment-1283 jackson Wed, 03 Nov 2010 17:25:05 +0000 http://jacksondunstan.com/?p=433#comment-1283 The point of the article is to show that getters and setters are slower than regular field access and are therefore an opportunity for optimization. To the extent that you use getters and setters rather than field access in your application, you'll slow it down. For example, if you have 100,000 particles in your scene and you use <code>Sprite</code>'s <code>get x</code>, <code>get y</code>, <code>set x</code> and <code>set y</code> once per particle, you'll make 400,000 getter/setter calls. At an average slowdown of 0.0000257ms per getter call (on the 2.0 Ghz Intel Core 2 Duo in the article) compared to <code>MySprite</code>, you'd incur a 10.28ms slowdown just in overhead for using getters. If you're trying to maintain 30 FPS, you've spent 30% of your available CPU time just on overhead. At 60 FPS, you've used 60%. If you just use a few hundred getters or setters per frame in your application, you probably don't need to worry about it. The point of the article is to show that getters and setters are slower than regular field access and are therefore an opportunity for optimization. To the extent that you use getters and setters rather than field access in your application, you’ll slow it down.

For example, if you have 100,000 particles in your scene and you use Sprite‘s get x, get y, set x and set y once per particle, you’ll make 400,000 getter/setter calls. At an average slowdown of 0.0000257ms per getter call (on the 2.0 Ghz Intel Core 2 Duo in the article) compared to MySprite, you’d incur a 10.28ms slowdown just in overhead for using getters. If you’re trying to maintain 30 FPS, you’ve spent 30% of your available CPU time just on overhead. At 60 FPS, you’ve used 60%.

If you just use a few hundred getters or setters per frame in your application, you probably don’t need to worry about it.

]]> By: Enrique http://jacksondunstan.com/articles/433/comment-page-1#comment-1279 Enrique Wed, 03 Nov 2010 12:28:35 +0000 http://jacksondunstan.com/?p=433#comment-1279 Are you sure the performance is slower in real applications? You are testing 10 million (!) of calls. And the diference is 60[ms] for MyPoint and MySprite. So calling 1million we are losing only 6ms, calling 100000 less than a 1[ms]... I think is not critical for performance. Is your application accesing 10millions of getters and setters every frame? Are you sure the performance is slower in real applications?
You are testing 10 million (!) of calls.
And the diference is 60[ms] for MyPoint and MySprite.
So calling 1million we are losing only 6ms, calling 100000 less than a 1[ms]… I think is not critical for performance.
Is your application accesing 10millions of getters and setters every frame?

]]> By: （ZZ）Flash Player 10.1 Performance | 傲天翔 の blog http://jacksondunstan.com/articles/433/comment-page-1#comment-903 （ZZ）Flash Player 10.1 Performance | 傲天翔 の blog Sun, 10 Oct 2010 10:17:58 +0000 http://jacksondunstan.com/?p=433#comment-903 [...] Original Article [...] [...] Original Article [...]

]]> By: jackson http://jacksondunstan.com/articles/433/comment-page-1#comment-832 jackson Wed, 15 Sep 2010 21:28:39 +0000 http://jacksondunstan.com/?p=433#comment-832 I agree that getters and setters provide a lot of flexibility. This article was mostly written as a caution that some of these frequently-used properties are getters and setters rather than properties. With that knowledge I wanted to show the performance consequences that implies and provide a simple tactic for improving performance for those who want to blend performance with the flexibility of getters and setters. I agree that getters and setters provide a lot of flexibility. This article was mostly written as a caution that some of these frequently-used properties are getters and setters rather than properties. With that knowledge I wanted to show the performance consequences that implies and provide a simple tactic for improving performance for those who want to blend performance with the flexibility of getters and setters.

]]> By: Henke37 http://jacksondunstan.com/articles/433/comment-page-1#comment-826 Henke37 Wed, 15 Sep 2010 17:29:18 +0000 http://jacksondunstan.com/?p=433#comment-826 There is a possible reason why some of them are setters and getters: real properties can't be overridden. The components in Flash does that as a part of their custom scaling logic. There is a possible reason why some of them are setters and getters: real properties can’t be overridden. The components in Flash does that as a part of their custom scaling logic.

]]> By: Germain LECOURTOIS http://jacksondunstan.com/articles/433/comment-page-1#comment-398 Germain LECOURTOIS Thu, 19 Nov 2009 16:03:25 +0000 http://jacksondunstan.com/?p=433#comment-398 I made a test with 10 000 000 iterations and had a getX() method. On a simple MyPoint class: public var _x:Number; public function getX() : Number { return _x;} public function get x() : Number { return _x;} Results : MyPoint.x: 2185 ms MyPoint.getX: 2444 ms MyPoint._x: 638 ms I made a test with 10 000 000 iterations and had a getX() method.
On a simple MyPoint class:
public var _x:Number;
public function getX() : Number { return _x;}
public function get x() : Number { return _x;}

Results :
MyPoint.x: 2185 ms
MyPoint.getX: 2444 ms
MyPoint._x: 638 ms

]]> By: jackson http://jacksondunstan.com/articles/433/comment-page-1#comment-363 jackson Tue, 10 Nov 2009 05:12:47 +0000 http://jacksondunstan.com/?p=433#comment-363 The <tt>MyPoint</tt> class is the test of getters without using <tt>Sprite</tt>. I added it because of Keith Peters' comment above. I'm not sure what you mean by using <tt>Vector</tt> and <tt>Dictionary</tt> classes here. How could this be faster than accessing a public variable? Could you provide a brief code example to show the technique? I'd be very interested to see any additional technique for solving the same problem other than what I've already discussed in the article. The MyPoint class is the test of getters without using Sprite. I added it because of Keith Peters’ comment above.

I’m not sure what you mean by using Vector and Dictionary classes here. How could this be faster than accessing a public variable? Could you provide a brief code example to show the technique? I’d be very interested to see any additional technique for solving the same problem other than what I’ve already discussed in the article.

]]> By: Elliot Rock http://jacksondunstan.com/articles/433/comment-page-1#comment-362 Elliot Rock Tue, 10 Nov 2009 04:59:38 +0000 http://jacksondunstan.com/?p=433#comment-362 Interesting test, it is a pretty self evident when you consider a getter setter does more but both contained public vars and getter/setters aren't great methods at tracking a large amount of iterations of classes/objects. Both the Vector and dictionary classes are better at retrieving and storing data like you are doing. But that is of course irrelevant to what you where trying to prove here. Good point over all, it would be good to see a raw test without sprites or using the display list. Interesting test, it is a pretty self evident when you consider a getter setter does more but both contained public vars and getter/setters aren’t great methods at tracking a large amount of iterations of classes/objects.

Both the Vector and dictionary classes are better at retrieving and storing data like you are doing.

But that is of course irrelevant to what you where trying to prove here. Good point over all, it would be good to see a raw test without sprites or using the display list.

]]> By: jackson http://jacksondunstan.com/articles/433/comment-page-1#comment-357 jackson Sat, 07 Nov 2009 16:22:24 +0000 http://jacksondunstan.com/?p=433#comment-357 No, <tt>MySprite</tt> already has public properties I directly access. One can assume the speed would be the same regardless of what the class is named. No, MySprite already has public properties I directly access. One can assume the speed would be the same regardless of what the class is named.

]]> By: Derrick Grigg http://jacksondunstan.com/articles/433/comment-page-1#comment-356 Derrick Grigg Sat, 07 Nov 2009 12:37:54 +0000 http://jacksondunstan.com/?p=433#comment-356 Did you run a test comparing the access of the getter/setter on the MyPoint class vs setting the __x and __y as public and accessing them directly? That would give you a true apples to apples comparison. Did you run a test comparing the access of the getter/setter on the MyPoint class vs setting the __x and __y as public and accessing them directly? That would give you a true apples to apples comparison.

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