I met a weird issue when I tried to search some logs during emulator booting.
When I create an emulator, the adb device started with "offline" first, then I type
adb logcat -v time | tee log1.txt
and adb will keep "wait-for-device" until the adb became online.
Then when the emulator boots up, I type adb logcat -v time | tee log2.txt again except the destination of the log file.
Now, I use vimdiff log1.txt log2.txt to compare these two logs and found log1 missed many logs as Log_Diff
I have no idea why some logs in log1.txt will missed.
Any ideas?
P.S. I am using Android 5.1-64bit Emulator in sdk.
After some research, finally I found the root cause in Android log daemon.
The main problem is the LogBufferElement is using a CLOCK_MONOTONIC timestamp as the sorting index.
When the timestamp of the multiple LogBufferElement are the same, LogReader may only dump the last entry. That's why some logs seem being lost.
AOSP Android 5.1 still had this issue, but Android 6.0 had fixed it.
You can refer to this patch.
Btw, I also did some modification for this patch.
The main reason is Android 6.0 supports the C++ 11 atomic std libs, but Android 5.1 is not yet. Some the atomic APIs need to roll back. (e.g. atomic_fetch_add_explicit())
Related
Suddenly my "adb pull" command will stuck in the middle of the process.
I'm not sure what cause it, after install some application or driver.
Happens for Pull one files or multiple files.
Does anyone encounter the same issue before? thanks.
Example:
U:\batch>adb pull /sdcard/xxxlog/mobilelog .\xxxlog\
[ 94%] /sdcard/xxxlog/mobilelog/APLog_xxx/main_log_1__xxx: 87%
Here a screenshot from my console
for my specific answer, and provide a possible answer to who encounter similar problem.
after I reinstall the whole os, testing different adb version,
the issue still remains.
during testing adb version,
I found the issue will not happens if i use Local Disk...
where issue happens when using Network Drive..
So a possible solution, is don't use Network drive
I encountered similar problem on adb server (v 1.0.40) started on Windows 7 machine. When tried to pull files from device on other machine running Linux in same local network (I used: "adb -H pull ...") the adb was freezing occasionally.
The solution was to not use Windows for ADB server.
This problem was NOT visible, when adb server was running on Linux VM (Ubuntu 16.4/ VirtualBox). Hope that this helps.
BR,
Ziggy
Every time I encounter this, it ends up being a max path length issue. Open a shell on the device using adb and review the file names within the directories that you are pulling. If any have exceedingly long names, they will silently fail and adb will hang
The thing that really throws you for a loop is that it usually fails after giving a percentage complete which makes you think it's a faulty connection or some other issue.
I haven't found a good way to recursively list out file names in shell and test their name length prior to doing the pull in order to know that the issue is going to happen, but when I have the same issue and rename long files, it ends up working on the next attempt.
I encountered the same problem when trying to transfer a large amount of data from an Android phone to a Raspberry Pi 3B+, and the logcat output seemed to reveal that adb was silently failing due to an issue with USB buffer reads (unfortunately, I don't have the exact message with me).
After the initial failure, it was possible to get another few files individually by unplugging the phone, running adb kill-server and adb start-server, and plugging it back in between each one, but the only longer-term fix I could find was restarting the Raspberry Pi. This solution, however, is not permanent, and must be repeated occasionally.
I was not able to replicate this issue on Windows or on a traditional Ubuntu system.
I encountered this problem while copying files from My Ubuntu machine to my Pixel 7.
A workaround based on this bug report, is to run
adb shell exit
in another terminal whenever it gets stuck until all files are copied. You can also run
watch -n 30 adb shell exit
to run the command every 30 seconds so you don't have to keep watching the process. I hope this helps someone.
I understand that this question has been asked 1000 times but every answer I can find on Stackoverflow and other websites are all the same: Either (1) The user is using Genymotion, (2) the user is using HTC Sync in Windows.
I am doing neither. I am currently running in OS/X (10.11.6) and am using a Moto X (2nd gen) phone running Android 6.0.
Many times (not every time) when I run "adb logcat", I get
adb server is out of date. killing...
* daemon started successfully *
This is a problem because I am trying to run some automated tests using gradlew (since using "adb shell am instrument" doesn't produce the JUnit style report I need) and collect logs... but every time I start "adb logcat", something in gradlew (apparently) tries to startup adb, which then kills all running instances of adb.
Has anyone seen this problem without using Genymotion/HTCSync/Windows and knows a solution?
Thanks!
The root cause of the server is out of date issue is still the same regardless the OS and/or other software used - you have multiple copies of adb binary in your system. And the solution is also the same:
kill all running adb processes
make sure you have the only copy of adb (remove the duplicates)
update it to the latest version
reconfigure all your software packages to use that copy
Just check that every tool you use is using the same adb version. For example, delete all versions except the latest.
Please check all your environmental paths which ADB has.
Your system may have several ADB.exe files so that mismatches makes the issue.
On Android Kitkat, the SELinux audit log can be found here:
/data/misc/audit/audit.log
However, I cannot find this file on Android 5.0 (Nexus 5). Any idea where I can get the audit log?
Either kmsg or logcat; auditd was never officially merged (oem specific).
adb shell dmesg
or
adb logcat
Note that the logcat version is not formated in a way understandable by audit2allow but the dmesg output is.
The auditd code for Android (I am the author of) was never merged onto AOSP and thus mainline Android, it was rejected here:
https://android-review.googlesource.com/#/c/51651/
Some OEMs picked the change back from either there or here:
https://bitbucket.org/seandroid/system-core/commits/branch/seandroid-4.3
See commits:
11389
e2cfa
The current implementation that routes the logs into logcat is under Change-Id: I421bcf33e7e670d596628b1b5c7c25536ce2d3fe (I could not post more than 2 links, so google for Android-Review and copy the change id starting with the capital I into the Gerrit search box)
This worked for me.
dmesg | grep 'avc: '
I've been experiencing a great deal of instability on my Verizon Galaxy S III, and I believe it's related to the WiFi driver, or at least something in the networking stack. I get daily full system crashes that cause soft reboots of the OS.
In order to trace to the root of the issue, I'd like to see historical crash data for the Android OS. Please note that I am NOT developing an app, and I do not want instruction on how to use LogCat to trace issues within an in-development app. I want to see the Android system crash logs, but I'm not sure where to look for them.
After ANR happens, you would find call stack of related process at /data/anr/traces.txt
After application crashes, you might find call stack of crashed application under /data/tombstones directory.
See Android: How to get kernel logs after kernel panic?
It looks like /data/dontpanic/ should contain some "apanic" files, but only if the kernel's apanic support is enabled, and it worked. (I haven't seen anything there in my case, but maybe you'll be luckier than I ...)
crash report can be found at default path: /data/anr/
some manufacture place in custom path like: /data/system/ckerror
use cmd: adb pull /data/anr "dest path"
example:
in windows cmd prompt:
adb pull /data/anr c:\trace
The document states that
Android stores trace information when it experiences an ANR. On older OS releases, there's >a single /data/anr/traces.txt file on the device.
On newer OS releases, there are multiple >/data/anr/anr_* files. You can access ANR traces from a device or emulator by using >Android Debug Bridge (adb) as root:
adb root
adb shell ls /data/anr
adb pull /data/anr/<filename>
Usually the every crash is stored in traces.txt file under /data/anr/ folder of internal storage. Try checking this file.
I found a file call crash.txt inside the directory /data/Logging which seems to contain brief stack-traces from the last several crashes that occurred on the device.
I know that the boot up log can be obtained by pulling out contents of kmsg or dmesg through ADB.
But I'm not aware of how to retrieve the shutdown logs in Android as there's no /var folder in Android (place where most desktop linux distros generally store their shutdown logs).
So how can I obtain the shutdown logs in Android?
Look in some locations such as these:
/proc/last_kmsg
/data/tombstones/
/data/dontpanic/
/data/system/dropbox/
(This list isn't strictly kernel logs, including framework and application logs too, which are also sometimes of interest)
One work around I found for collecting shutdown logs in Android is to run adb pull /proc/kmsg C:\Logs.txt on the host PC and then switch off the device. You will get the logs till the USB communication between the host and the device snaps! I know this is only one case out of the numerous shutdown scenarios but I haven't found satisfactory answers for other cases!
TL;DR:
Run command through adb that copies logcat and proc/kmsg to a file and keep it running even when adb disconnects with nohup, disown or setsid. Probably needs busybox, needs root and adb root, too.
setsid cat proc/kmsg > /sdcard/kmsg.txt &
and
logcat -v long -f /sdcard/logcat.txt (somehow only works without setsid)
Or add normal copy commands to some startup script.
/TL;DR
You can constantly copy proc/kmsg and logcat to a file on your android device or a microSD card to get the logs even after adb disconnects.
You need root access and adb root access for this to work. For the latter, use the setting in the developer options if you have a custom rom or the adbd insecure app.
After using adb shell to get your android shell, type su to get superuser access.
Then you not only need to put an ampersand (&) after the command but also make sure that the command keeps running after adb disconnects. That is done by nohup, disown or setsid (see here for usage).
If it doesn't work because you don't have these commands, you need to install busybox.
See my question here.
See here for how to get logcat and kernel logs and print it to some file or merge it.
See developer.android.com/tools/help/logcat.html for parameters for the logcat command.
In the end you could have a command like setsid cat proc/kmsg > /sdcard/kmsg.txt & for the kernel messages.
For logcat you could have one of the following commands: logcat -v long -f /sdcard/logcat.txt or logcat -v long > /sdcard/logcat.txt
I don't know why, but sometimes it didn't work with setsid and just didn't copy continuously but stopped shortly after executing the command. In these situations, it also showed up when entering jobs, which it didn't otherwise. Then it just worked without setsid, it stayed alive after disconnecting and reconnecting. I guess you must just try when the file does keep getting larger. If someone figured out why it is behaving like it is... let me know and I'll edit the answer.
Probably adding the commands to a startup script could be a solution for some, too.
Hope this helps.
fightcookie
Newer phones do NOT use any of these locations so if you're reading this article then as of now
The kernel crash logs are now in /sys/fs/pstore instead of /proc/last_kmsg
I was looking for the same thing, and finally, I found the answer!
In android 8 all logs are located in \data\log\android_logs\... including apps and kernel logs. Kernel logs are called kmsgcat-log_timestamp_.gz
edit: Although this is a very old thread, I think the answer might be helpful.