Re: [PATCH v5] ANDROID: binder: change down_write to down_read

[Greg Kroah-Hartman]

On Mon, Apr 16, 2018 at 06:17:48PM +0900, Minchan Kim wrote:
> Hi Ganesh,
> 
> On Tue, Apr 10, 2018 at 04:52:58PM +0800, Ganesh Mahendran wrote:
> 
> < snip >
> > >>             base            patch_v1         patch_v5
> > >> -----------------------------------------------------------
> > >>             91223.4      90560.2           89644.5
> > >>             90520.3      89583.1           89048.2
> > >>             89833.2      90247.6           90091.3
> > >>             90740.2      90276.7           90994.2
> > >>             89703.5      90112.4           89994.6
> > >>             89945.1      89122.8           88937.7
> > >>             89872.8      90357.3           89307.4
> > >>             89913.2      90355.4           89563.8
> > >>             88979         90393.4           90182.8
> > >>             89577.3      90946.8           90441.4
> > >> AVG    90030.8      90195.57          89820.59
> > >
> > > Yes, no regression.
> > >
> > >>
> > >> Before the test, I stop the android framework by:
> > >>     adb shell stop
> > >>
> > >> >
> > >> > Please tell me more detail. What apps are slower compared to old?
> > >> > Every apps are slowed with avg 15%? Then, what's the stddev?
> > >>
> > >> Not all of the apps slowed 15%, The app *avg* launch time slowed 15%.
> > >> And We will re-launch the test tomorrow: base, v1,v5. We will get the
> > >> test result in two days later. Then I will post all the app launch time details.
> > >
> > > I'm also trying to make stable result in my side but it's really hard to
> > > get. Please post stddev of each app as well as avg when you finished testing.
> > > I really appreicate you.
> > 
> > What do you mean by stddev?
> 
> Standard deviation.
> 
> > 
> > We test 80 loops and launch ~40 apps in each loop.
> > Below is the app launch time result:
> > 
> > app base v1 diff percent v5 diff percent
> > ----
> > com.tencent.mobileqq 829 834 5 1% 879 50 6%
> > com.tencent.qqmusic 799 790 -9 -1% 764 -35 -4%
> > com.tencent.mtt 659 655 -4 -1% 979 320 49%
> > com.UCMobile 1149 1144 -5 0% 927 -222 -19%
> > com.qiyi.video 1557 1579 22 1% 1497 -60 -4%
> > com.baidu.BaiduMap 1137 1136 -1 0% 1096 -41 -4%
> > tv.danmaku.bili 3642 3655 13 0% 3538 -104 -3%
> > com.sdu.didi.psnger 4334 4352 18 0% 4224 -110 -3%
> > com.ss.android.ugc.aweme 1958 1970 12 1% 1884 -74 -4%
> > air.tv.douyu.android 3333 3371 38 1% 3251 -82 -2%
> > me.ele 3183 3182 -1 0% 3178 -5 0%
> > com.autonavi.minimap 1920 1922 2 0% 1868 -52 -3%
> > com.duowan.kiwi 1452 1457 5 0% 1349 -103 -7%
> > com.v.study 3549 3558 9 0% 3519 -30 -1%
> > com.qqgame.hlddz 4074 4060 -14 0% 4443 369 9%
> > com.ss.android.article.news 1631 1680 49 3% 1649 18 1%
> > com.jingdong.app.mall 1448 1443 -5 0% 1323 -125 -9%
> > com.tencent.tmgp.pubgmhd 1703 1706 3 0% 1601 -102 -6%
> > com.kugou.android 854 862 8 1% 791 -63 -7%
> > com.kuaikan.comic 1341 1374 33 2% 2118 777 58%
> > com.smile.gifmaker 798 686 -112 -14% 642 -156 -20%
> > com.hunantv.imgo.activity 1560 1616 56 4% 1569 9 1%
> > com.mt.mtxx.mtxx 1746 1838 92 5% 1773 27 2%
> > com.sankuai.meituan 3610 3697 87 2% 3551 -59 -2%
> > com.sankuai.meituan.takeoutnew 3376 3387 11 0% 3325 -51 -2%
> > com.meitu.meiyancamera 1905 2010 105 6% 1870 -35 -2%
> > com.tencent.karaoke 888 906 18 2% 896 8 1%
> > com.taobao.taobao 3344 3406 62 2% 3368 24 1%
> > com.tencent.qqlive 1314 1345 31 2% 1499 185 14%
> > com.tmall.wireless 3746 3735 -11 0% 3699 -47 -1%
> > com.tencent.tmgp.sgame 3250 3513 263 8% 3707 457 14%
> > com.netease.cloudmusic 2550 2570 20 1% 2546 -4 0%
> > com.sina.weibo 2201 2240 39 2% 2191 -10 0%
> > com.tencent.mm 638 645 7 1% 690 52 8%
> > com.immomo.momo 1536 1554 18 1% 1563 27 2%
> > com.xiaomi.hm.health 915 926 11 1% 888 -27 -3%
> > com.youku.phone 1881 1820 -61 -3% 1880 -1 0%
> > com.eg.android.AlipayGphone 1536 1557 21 1% 1624 88 6%
> > com.meituan.qcs.c.android 3140 3533 393 13% 3171 31 1%
> > -----
> > average 2064 2095 31 1.50% 2085 21 1%
> > 
> > 1% is in the fluctuating range of our tool.
> > So no obvious regression found in app launch time.
> 
> Thanks.
> 
> Greg, Ganesh finally confirmed there is no regression.
> Could you pick up the patch?

If there is no regression, and no speed up either, why is it needed?  :)

And is app launch time really the best binder benchmark?  What about the
throughput and latency tests?  Do those show any changes?  I'm kind of
lost as to what is really happening here, sorry, the merge window is not
the time for me to be keeping track of this type of thing...

thanks,

greg k-h