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Re: GamepadObserver (ie. MutationObserver + Gamepad)

From: Olli Pettay <Olli.Pettay@helsinki.fi>
Date: Tue, 07 Aug 2012 12:31:53 +0300
Message-ID: <5020E089.1050207@helsinki.fi>
To: Glenn Maynard <glenn@zewt.org>
CC: Florian Bösch <pyalot@gmail.com>, Scott Graham <scottmg@chromium.org>, Rick Waldron <waldron.rick@gmail.com>, Webapps WG <public-webapps@w3.org>, Ted Mielczarek <ted@mielczarek.org>
On 08/07/2012 03:29 AM, Glenn Maynard wrote:
> On Sat, Aug 4, 2012 at 4:24 AM, Olli Pettay <Olli.Pettay@helsinki.fi <mailto:Olli.Pettay@helsinki.fi>> wrote:
>
>     5ms is quite low when the aim is 60Hz updates... but with incremental/generational GCs 5ms sounds very much possible.
>
>
> 5ms is an *eternity* when you're aiming for 60 FPS, where you only have 16.6ms per frame to play with.  That's 30% of your CPU budget just for memory
> management.  It doesn't matter if it's 5ms every 100 frames, since it's the worst case you have to optimize for.  (I've spent a lot of time optimizing
> non-web games to stay at 60 FPS, and it's a battle of microseconds, optimizing away .1ms here and .2ms there, so calling 5ms "quite low" is a bit
> troubling.)

It is quite different if you need to assume that GC takes 180-250ms or if it takes only 5ms.
But sure, getting anything major done in <16.6ms, and even so that things work ok on slower machines too can be tricky.
Received on Tuesday, 7 August 2012 09:32:29 GMT

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