Dianne, Assume what you will, but your assumptions may not reflect the facts. I posted my closing down statement hours before you sent your slightly insulting email. As you've raised a couple of new issues I'd like to point out a couple of inaccuracies in what you've said; 1) Most windows games go to the highest priority level when they take up the whole screen because they are the foreground app and most windows configurations give that process priority. When you find games that will run in a window you should compare their windowed performance to their full screen performance on a single core machine (like the G1 effectively is), you'll see a noticeable difference. Even if you are running a windows game full screen it can still judder and slow down if you're on a single core machine (try doing an Antivirus scan at the same time as running a game on a single core machine to get a roughly equivalent experience to what can happen on a single core G1). A lot of the improvements in performance have come from more RAM for caching, being able to offload work onto a GPU, and/or spreading workload over multiple cores. Very little has come from improvements to the core OS. 2) The posting of that link wasn't snide. You talked about implementing a scheduling category system, the link was to a doc showing that the facility already exists in Linux. Nothing snide, nothing unpleasant, you showed a lack of understanding of the details of Linux scheduler (which you've now admitted to) so I posted a link to help you understand the area you were commenting on. If you chose to interpret my email that way then that's you're choice. Al.
_____ From: [email protected] [mailto:[email protected]] On Behalf Of Dianne Hackborn Sent: 27 March 2009 16:40 To: [email protected] Subject: [android-developers] Re: Anything on Android that can do smooth scrolling? Okay I have to assume at this point that you two are actually trolling. First, NOBODY has said that it isn't important to be able to do well performing games. The only discussion here is about how to achieve that. (And Al, I don't need some snide little link to a doc on Linux kernel scheduling; I am generally aware of how scheduling in the kernel works, but not deeply involved in the details, because we have other kernel engineers who are and spend extensive amounts of time in the code of the scheduler getting it to work well in our system, and looking at how to modify it to help with the background app situation.) Second, I find it faintly surreal to see these repeated claims that the only way to possibly allow for decent games is to have some "only my app can run" option, when people have been doing well performing games on Windows for years. Ages ago this was because they could be the only one running, but that hasn't been the case for years. This is basically a well known problem and there are well known solutions. (And now, the "prefer foreground apps" option is NOT the same; that should be the normal default behavior on Android.) Third, "oh just let the foreground app be the only one running" opens up a huge can of worms, as has already been pointed out. Clearly it's not the -only- thing running, because you still want to receive phone calls, so the phone app is special... gee for the people complaining about that, I guess we should be glad we don't allow third party apps to replace it! :} Or if we did, or we wanted -anything- else to happen while this game is going, then apps have some facility to declare that they get to override the override, and it just escalates from that. Again, there are well known ways to deal with these issues, and a special "this is the only app running (wink wink)" mode is not it. On Fri, Mar 27, 2009 at 4:11 AM, Al Sutton <[email protected]> wrote: What I'm advocating is the "Building on the shoulders of giants" principal. To start with we get to where everyone else is by using commonly accepted techniques (i.e. limiting background tasks), then we improve on it. Yes I am looking at one case, but in terms of revenue it's the big one, and that means it'll draw in developers and provide a base which can sustain companies focused on Android. and as yet there still seems to be no focus on who Android should appeal to which runs the risk of it becoming a jack of all trades but master of none. Al. -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Romain Guy Sent: 27 March 2009 10:17 To: [email protected] Subject: [android-developers] Re: Anything on Android that can do smooth scrolling? You are looking at *ONE* use case. Android is trying to provide an efficient system to the users that also allows background apps. I'm not saying it's an easy problem to solve, I'm saying that the comparison with some other devices out there is moot when they're not trying to reach the same goals. We would all very much like to see this issue disappear and what we need is hard data and discussions on how to solve this issue. But discarding background apps is not the appropriate solution, it's just one easy solution. On Fri, Mar 27, 2009 at 3:06 AM, Al Sutton <[email protected]> wrote: > > I guess it comes down to the choice of do we want high performance > games on Android or not. > > At the moment it seems clear that due to the ability of background > tasks to continue running it is next to impossible to provide > predictable performance for resource demanding games on all users > devices and thus games can not make the most out of the hardware > without risking 1* ratings and being called laggy by those running a number of background apps. > > Maybe this is where Android is trying to be different. Maybe games are > not best suited to an Android based platform because of this. I guess > time and users will be the judge of whether this is the right way to go. > > Personally I don't think it is, but hey, I'm only one voice. > > Al. > > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Romain Guy > Sent: 27 March 2009 09:47 > To: [email protected] > Subject: [android-developers] Re: Anything on Android that can do > smooth scrolling? > > > No, I was not pointing back to this idea. > > And the PS3 does that because it's a *video game console.* On which > you usually do *one thing at a time.* > > On Fri, Mar 27, 2009 at 2:44 AM, Al Sutton <[email protected]> wrote: >> >> And once again we get pointed back to the idea of pausing most (if >> not >> all) background apps to achieve a good user experience. >> >> Even the PS3 which has far better hardware than the G1 goes down this >> route as it pauses the game just to bring up an in-game menu. The >> only thing it ever tries to run in the background is the PlayTV >> system and that comes with a big warning about affecting game performance. >> >> Al. >> >> -----Original Message----- >> From: [email protected] >> [mailto:[email protected]] On Behalf Of Romain Guy >> Sent: 27 March 2009 09:38 >> To: [email protected] >> Subject: [android-developers] Re: Anything on Android that can do >> smooth scrolling? >> >> >> Yeah... none of them have background apps. >> >> On Fri, Mar 27, 2009 at 2:33 AM, Al Sutton <[email protected]> wrote: >>> >>> Ahh so that's how the PSP, DS, and iPhone do it.... Hold up, that >>> doesn't sound right... :). >>> >>> Al. >>> >>> -----Original Message----- >>> From: [email protected] >>> [mailto:[email protected]] On Behalf Of Romain Guy >>> Sent: 26 March 2009 22:12 >>> To: [email protected] >>> Subject: [android-developers] Re: Anything on Android that can do >>> smooth scrolling? >>> >>> >>> Have multiple cores :) >>> >>> On Thu, Mar 26, 2009 at 3:10 PM, Stoyan Damov >>> <[email protected]> >>> wrote: >>>> >>>> On Thu, Mar 26, 2009 at 11:53 PM, Romain Guy <[email protected]> >> wrote: >>>>> >>>>> Once again it has NOTHING to do with GC, it's just another app >>>>> using the CPU. It could be for any reason, not just GC. >>>>> >>>>> I hope you get it now. >>>>> >>>> >>>> Aaaaaaaah, @#$ me. I GET it now! >>>> >>>> Thanks Romain, and thanks again for patiently explaining this >>>> several >>> times! >>>> >>>> So, we're back then to square 1 - how do we make Android *appear* >>>> that it runs an application exclusively. >>>> That is, what's the best way to ensure great user experience for >>>> demanding apps, such as games, without pausing all other processes. >>>> >>>> Any ideas besides the permission thing, anyone? >>>> >>>> Cheers >>>> >>>> > >>>> >>> >>> >>> >>> -- >>> Romain Guy >>> Android framework engineer >>> [email protected] >>> >>> Note: please don't send private questions to me, as I don't have >>> time to provide private support. All such questions should be >>> posted on public forums, where I and others can see and answer them >>> >>> >>> >>> >>> > >>> >> >> >> >> -- >> Romain Guy >> Android framework engineer >> [email protected] >> >> Note: please don't send private questions to me, as I don't have time >> to provide private support. All such questions should be posted on >> public forums, where I and others can see and answer them >> >> >> >> >> > >> > > > > -- > Romain Guy > Android framework engineer > [email protected] > > Note: please don't send private questions to me, as I don't have time > to provide private support. All such questions should be posted on > public forums, where I and others can see and answer them > > > > > > > -- Romain Guy Android framework engineer [email protected] Note: please don't send private questions to me, as I don't have time to provide private support. All such questions should be posted on public forums, where I and others can see and answer them -- Dianne Hackborn Android framework engineer [email protected] Note: please don't send private questions to me, as I don't have time to provide private support. 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