Could root be a cause of some app "hang" issues? (would appreciate devs looking)

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So, after being really fed up with the fact that since the latest update the Fox News app very often will get into a state where it's stuck using ~50% CPU (likewise for Facebook App), and receiving no word back after emailing the devs, I decided to try and delve a bit deeper. Finally got strace running on my phone tonight and was able to discover this output the next time it got into the "hung" state (note, the app is still completely usable, it's just the CPU becomes pegged at 50% for the app... also, there's never any obvious messages in logcat, hence my attempts with strace):

app_101@android:/data # strace -p 1552
Process 1552 attached - interrupt to quit
futex(0x409b7f78, FUTEX_WAIT_PRIVATE, -2460, NULL) = 0
futex(0x409b7f74, FUTEX_WAIT_PRIVATE, 2, NULL) = 0
futex(0x409b7f74, FUTEX_WAKE_PRIVATE, 1) = 0
clock_gettime(CLOCK_MONOTONIC, {41871, 859736583}) = 0
epoll_wait(0x23, 0xbef4f450, 0x10, 0xffffffff

) = 1
read(33, "W"..., 16)                    = 1
clock_gettime(CLOCK_MONOTONIC, {41938, 717839115}) = 0
getpid()                                = 1552
gettid()                                = 1552
clock_gettime(CLOCK_MONOTONIC, {41938, 726950073}) = 0
ioctl(9, 0xc0186201, 0xbef4e430)        = 0
clock_gettime(CLOCK_MONOTONIC, {41938, 727448031}) = 0
getpid()                                = 1552
getuid32()                              = 10057
epoll_wait(0x23, 0xbef4f450, 0x10, 0)   = 0
clock_gettime(CLOCK_MONOTONIC, {41938, 728984198}) = 0
epoll_wait(0x23, 0xbef4f450, 0x10, 0xffffffff) = -1 EINTR (Interrupted system call)
clock_gettime(CLOCK_MONOTONIC, {41940, 224115698}) = 0
getpid()                                = 1552
getuid32()                              = 10057
epoll_wait(0x23, 0xbef4f450, 0x10, 0)   = 1
read(33, "W"..., 16)                    = 1
clock_gettime(CLOCK_MONOTONIC, {41940, 226861031}) = 0
epoll_wait(0x23, 0xbef4f450, 0x10, 0xffffffff) = 1
read(33, "W"..., 16)                    = 1
clock_gettime(CLOCK_MONOTONIC, {41953, 401456621}) = 0
getpid()                                = 1552
gettid()                                = 1552
clock_gettime(CLOCK_MONOTONIC, {41953, 402554246}) = 0
ioctl(9, 0xc0186201, 0xbef4e430)        = 0
clock_gettime(CLOCK_MONOTONIC, {41953, 402836288}) = 0
getpid()                                = 1552
getuid32()                              = 10057
epoll_wait(0x23, 0xbef4f450, 0x10, 0)   = 0
clock_gettime(CLOCK_MONOTONIC, {41953, 406251955}) = 0
epoll_wait(0x23, 0xbef4f450, 0x10, 0xffffffff) = 1
read(33, "W"..., 16)                    = 1
clock_gettime(CLOCK_MONOTONIC, {41953, 587922288}) = 0
getpid()                                = 1552
gettid()                                = 1552
clock_gettime(CLOCK_MONOTONIC, {41953, 598259204}) = 0
ioctl(9, 0xc0186201, 0xbef4e430)        = 0
ioctl(9, 0xc0186201, 0xbef4e430)        = 0
clock_gettime(CLOCK_MONOTONIC, {41953, 627380080}) = 0
futex(0x409b816c, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b8164, FUTEX_WAKE_PRIVATE, 1) = 1
mprotect(0x51d88000, 108, PROT_READ|PROT_WRITE|PROT_EXEC) = 0
cacheflush(0x51d88068, 0x51d8806c, 0, 0xfff, 0x409b8130) = 0
mprotect(0x51d88000, 108, PROT_READ|PROT_EXEC) = 0
futex(0x409b816c, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b8164, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b816c, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b8164, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b816c, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b8164, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b816c, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b8164, FUTEX_WAKE_PRIVATE, 1) = 1
mprotect(0x51d88000, 216, PROT_READ|PROT_WRITE|PROT_EXEC) = 0
cacheflush(0x51d880d4, 0x51d880d8, 0, 0xfff, 0x409b8130) = 0
mprotect(0x51d88000, 216, PROT_READ|PROT_EXEC) = 0
getpid()                                = 1552
getuid32()                              = 10057
epoll_wait(0x23, 0xbef4f450, 0x10, 0)   = 0
clock_gettime(CLOCK_MONOTONIC, {41953, 645792663}) = 0
ioctl(9, 0xc0186201, 0xbef4f590)        = 0
epoll_wait(0x23, 0xbef4f450, 0x10, 0xffffffff) = -1 EINTR (Interrupted system call)
clock_gettime(CLOCK_MONOTONIC, {41954, 869117871}) = 0
epoll_wait(0x23, 0xbef4f450, 0x10, 0xffffffff) = 1
read(33, "W"..., 16)                    = 1
clock_gettime(CLOCK_MONOTONIC, {41955, 55892538}) = 0
getpid()                                = 1552
getuid32()                              = 10057
epoll_wait(0x23, 0xbef4f450, 0x10, 0)   = 0
clock_gettime(CLOCK_MONOTONIC, {41955, 95623955}) = 0
epoll_wait(0x23, 0xbef4f450, 0x10, 0xffffffff) = 1
read(33, "W"..., 16)                    = 1
clock_gettime(CLOCK_MONOTONIC, {41960, 829853457}) = 0
getpid()                                = 1552
gettid()                                = 1552
clock_gettime(CLOCK_MONOTONIC, {41960, 830388416}) = 0
ioctl(9, 0xc0186201, 0xbef4e430)        = 0
ioctl(9, 0xc0186201, 0xbef4e430)        = 0
clock_gettime(CLOCK_MONOTONIC, {41960, 883238124}) = 0
futex(0x409b816c, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b8164, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b816c, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b8164, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b816c, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b8164, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b816c, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b8164, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b816c, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x409b8164, FUTEX_WAKE_PRIVATE, 1) = 1

During this, the screen slept twice, so there was two unlocks in there (and the subsequent returns to the terminal app). Other than that, it's just the strace output. Mainly the futex lines though are what looked suspicious. It's obviously waiting for SOMETHING... that's just never firing. A quick search came across this (hence the reason for my post):

http://lkml.indiana.edu/hypermail/li...3.0/02451.html

I know that just because the phone is rooted, apps aren't by default running as root... just trying to figure out what could be causing this odd behavior, since the devs are no f'ing help thus far.... and I'm bored waiting for the OTA

Thanks.

Its probably something wrong with the faux news app and nothing to do with root. Why don't you just use Google news or ap mobile? If fox is the only news app you trust, your problems are a lot bigger than battery drain.

Sent from my SPH-D710 using Tapatalk 2

Originally Posted by tmeader

I know that just because the phone is rooted, apps aren't by default running as root... just trying to figure out what could be causing this odd behavior, since the devs are no f'ing help thus far.... and I'm bored waiting for the OTA

It is highly doubtful root has anything to do with this. Root is essentially dormant unless you ask to use it. The first time an app asks to use it, you get a prompt on the screen. After that you permission to use root is stored.

Start the superuser app and see if fox news has any entries, if not, it isn't using root.

The futex_wake() are for 2 different addresses. I didn't see a futex_wait() for either of them in your strace.

The getuid() all say 10057. At least if you saw some stuff that said uid (or effective uid) being 0 that might point to root being involved.

If you still feel it is root, rename /system/xbin/su to /system/xbin/su-new

If the app still is problematic, clearly it isn't using root.

Originally Posted by sfhub

It is highly doubtful root has anything to do with this. Root is essentially dormant unless you ask to use it. The first time an app asks to use it, you get a prompt on the screen. After that you permission to use root is stored.

Start the superuser app and see if fox news has any entries, if not, it isn't using root.

The futex_wake() are for 2 different addresses. I didn't see a futex_wait() for either of them in your strace.

The getuid() all say 10057. At least if you saw some stuff that said uid (or effective uid) being 0 that might point to root being involved.

If you still feel it is root, rename /system/xbin/su to /system/xbin/su-new

If the app still is problematic, clearly it isn't using root.

Thanks. Doubted it could have anything to do with it, since there was no request for root on app launch. But since I finally tracked down a copy of strace, figured I'd give the output a shot. Either way, nice to at least find that I'm not crazy, and that the app IS doing something, despite not logging a damn thing.

Originally Posted by Atticuspoint6

Its probably something wrong with the faux news app and nothing to do with root. Why don't you just use Google news or ap mobile? If fox is the only news app you trust, your problems are a lot bigger than battery drain.

Sent from my SPH-D710 using Tapatalk 2

Actually, I wanted to use the Google News and Weather App that I originally used with my LG Optimus S (I don't want to just use Google News via the browser). But evidently Samsung didn't see fit to include that, and I can't seem to find the apk for that anywhere readily. Previous I'd tried the others: CNN, ABC, USA Today. Those were all worse. Much much too "heavy" for a mobile app.

AP Mobile actually looks pretty great though. Might just go with this (unless you know where I can get a copy of Google News and Weather?)

Thanks for the suggestions (indirect or not ).