These are results of 'top' running the (unmodified) CameraPreview of the ApiDemos sample on two Nexus S devices, one with Gingerbread, the other one with Ice Cream Sandwich:
1) Nexus S, Gingerbread, Build Target: Android 2.3.3 User 1%, System 6%, IOW 0%, IRQ 0% User 6 + Nice 0 + Sys 21 + Idle 282 + IOW 0 + IRQ 0 + SIRQ 0 = 309 PID TID CPU% S VSS RSS PCY UID Thread Proc 1138 1138 3% R 1092K 528K fg shell top top 75 1142 1% D 32312K 4500K fg media CameraPreviewTh /system/bin/mediaserver 114 125 0% D 192872K 62016K fg system system_server system_server 182 182 0% S 103024K 27104K fg system ndroid.systemui com.android.systemui 114 126 0% S 192872K 62016K fg system SensorService system_server 2) Nexus S, ICS, Build Target: Android 2.3.3 User 28%, System 21%, IOW 0%, IRQ 0% User 90 + Nice 0 + Sys 69 + Idle 157 + IOW 0 + IRQ 0 + SIRQ 1 = 317 PID TID PR CPU% S VSS RSS PCY UID Thread Proc 81 2509 0 17% S 49372K 5100K fg media CameraPreviewTh /system/bin/mediaserver 78 131 0 15% S 39576K 17648K fg system SurfaceFlinger /system/bin/surfaceflinger 162 175 0 4% D 356748K 46212K fg system system_server system_server 2478 2478 0 3% R 1188K 588K fg shell top top 162 177 0 1% S 356748K 46212K fg system er.ServerThread system_server 3) Nexus S, ICS, Build Target: Android 4.0.3 User 44%, System 15%, IOW 0%, IRQ 0% User 140 + Nice 0 + Sys 50 + Idle 128 + IOW 0 + IRQ 0 + SIRQ 0 = 318 PID TID PR CPU% S VSS RSS PCY UID Thread Proc 81 2931 0 38% S 55904K 8412K fg media CameraPreviewTh /system/bin/mediaserver 78 131 0 7% S 45432K 22484K fg system SurfaceFlinger /system/bin/surfaceflinger 2921 2921 0 3% R 1188K 588K fg shell top top 162 175 0 2% D 356860K 47052K fg system system_server system_server 2718 2718 0 1% S 0K 0K fg root kworker/0:1 Indeed, one does not even need to perform any additional (native) processing to find that the mediaserver and surfaceflinger processes are consuming an unhealthy amount of CPU power on Ice Cream Sandwich. Note that the exact behavior even changes with different build targets; ~30% of CPU time are already bad when building against Android 2.3.3, but it gets a lot worse with ~45% when building against Android 4.0.3. Am planning to file a bug report. On Thursday, March 1, 2012 6:53:08 PM UTC+1, Chris Stratton wrote: > > > On Thursday, March 1, 2012 12:08:31 PM UTC-5, Michael wrote: >> >> Good tip! This is a print from top running the test application on a >> Nexus S with Gingerbread: >> >> User 89%, System 3%, IOW 0%, IRQ 0% >> User 282 + Nice 0 + Sys 12 + Idle 22 + IOW 0 + IRQ 0 + SIRQ 0 = 316 >> PID TID CPU% S VSS RSS PCY UID Thread Proc >> 771 771 86% R 104220K 27216K fg app_54 PerformanceTest >> com.ICSPerformanceTest >> > > >> And this is the exact same application on a Nexus S with Ice Cream >> Sandwich: >> >> User 87%, System 9%, IOW 0%, IRQ 0% >> User 287 + Nice 0 + Sys 32 + Idle 9 + IOW 0 + IRQ 0 + SIRQ 0 = 328 >> PID TID PR CPU% S VSS RSS PCY UID Thread Proc >> 2849 2849 0 57% R 278568K 35372K fg app_66 PerformanceTest >> com.ICSPerformanceTest >> 81 2867 0 28% S 56408K 9196K fg media CameraPreviewTh >> /system/bin/mediaserver >> > > >> We still don't know why this is happening, though. It's not an active >> face detection - we double-checked that. A quick look through the Android >> source code didn't give any insight either. Though my suspicion is that >> either something is wrong with the ICS implementation or the camera driver. >> It would be nice to get more info on that, and potential solutions to fix >> the issue. >> > > You could try and see if you can get git to give up a diff of the relevant > files in mediaserver between the two versions of Android, but that may be a > lengthy path to follow. > > It would be interesting if you could reproduce the same difference in > mediaserver CPU usage with someone else's code that doesn't do any (even > dummy) native processing. Could you try the CamerPreview in the ApiDemos > of the sdk samples? If you can reproduce the mediaserver CPU load > reflected by top with that you'd clearly be in a position to file a bug > report. > -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
