[Bug]: Android 12 Phantom Processes Killed "[Process completed (signal 9) - press Enter]"

[V-no-A]

Edit: Check this comment for solution.

---

Problem description

I get a message saying [Process completed (signal 9) - press Enter] at, seemingly, random intervals. Once I press Enter, Termux closes. This may happen while I am running a Python script or simply under the "Welcome to Termux!" text after leaving Termux idle for a while (leaving the app/turning off the screen) and not having run any commands.

Steps to reproduce the behavior.

I upgraded my Pixel 3a phone to Android 12 and downloaded Termux from F-Droid as well as Termux:API. I did the termux-setup-storage command and gave the app unrestricted battery usage under the Android Apps settings. Lastly, I installed Python using pkg install python.

What is the expected behavior?

Previously, on Android 11, I had installed Termux from the Google Play Store. Not once did I ever get that [Process completed (signal 9) - press Enter] message. I was able to leave Termux running in the background indefinitely.

System information

• Termux application version:
  0.117
• Android OS version:
  12
• Device model:
  PIxel 3a

[Grimler91]

Do you get anymessages in an adb logcat when termux is killed?

[V-no-A]

adb logcat

I'm looking at the logcat.txt file right now but I do not know exactly what I should be looking for since this is my introduction to them.

What should I show you? Everything around the time that I hit Enter? Or everything since I open up Termux up to when I get the "[Process completed (signal 9) - press Enter]" message?

[Grimler91]

Something like all messages from when termux is killed and 15 s before and after should be interesting (you could also share the entire log if you are confident it does not contain sensitive information).

What I am curious about is if there is any messages from "android"/"system"/"low memory killer" or something else that indicates that termux is killed, and in that case why.

I don't think any maintainer has a device with android 12 yet, so might be specific for recent android versions

[V-no-A]

Something like all messages from when termux is killed and 15 s before and after should be interesting (you could also share the entire log if you are confident it does not contain sensitive information).

I'll do the 15 seconds before and after since I'm not confident the entire log won't contain anything I wouldn't want public. I'll show more if needed. Though it'll have to be in 12 hours or so.

I don't think any maintainer has a device with android 12 yet, so might be specific for recent android versions

I'm leaning on it being Android 12 related. Reason I reinstalled Termux was because I got an error on it (cannot recall if it was this same one) right after I updated the phone. I was looking for a reason to change to the F-Droid version from the Google Store and did it immediately without thinking much about the message I got.

[V-no-A]

Sorry, I was having a hard time getting the error message again.

Since I did not exactly know what to include from the logcat, I created and ran a Python script that writes the time to a txt file. The last written time was "2021-10-29 16:25:52.242" before being interrupted by [Process completed (signal 9) - press Enter] once again. Here are a few messages at and around that time:

10-29 16:25:50.345  3942  4103 D SharedPreferencesImpl: Time required to fsync /data/user/0/com.weather.Weather/shared_prefs/ALCrashTracker.xml: [<1: 5, <2: 62, <4: 104, <8: 767, <16: 78, <32: 2, <64: 4, <128: 1, <256: 1, <512: 0, <1024: 0, <2048: 0, <4096: 0, <8192: 0, <16384: 0, >=16384: 0]
10-29 16:25:52.246  1664  1834 I ActivityManager: Killing PhantomProcessRecord {4cb7847 6789:17247:python/u0a383}: Trimming phantom processes
10-29 16:25:52.247  1664  1834 I ActivityManager: Killing PhantomProcessRecord {7320874 6756:17247:bash/u0a383}: Trimming phantom processes
10-29 16:25:52.256  1664  1848 I libprocessgroup: Successfully killed process cgroup uid 10383 pid 6789 in 0ms
10-29 16:25:52.257  1664  1848 I ActivityManager: Process PhantomProcessRecord {7320874 6756:17247:bash/u0a383} died
10-29 16:25:52.257  1664  1848 I ActivityManager: Process PhantomProcessRecord {4cb7847 6789:17247:python/u0a383} died
10-29 16:25:52.257  1664  1848 I libprocessgroup: Successfully killed process cgroup uid 10383 pid 6756 in 0ms
10-29 16:26:06.077  3750  4042 I WorkerManager: dispose()
10-29 16:26:13.233   968  1224 I CHRE    : @ 9785.504: [ImuCal] [NanoSensorCal:GYRO_RPS] Offset | Temperature [C]: 0.000231, -0.000705, -0.001613 | 38.16

I should've probably mentioned, although wakelock was on, I have gotten the message with it turned off.
And, even though this happened while running the Python script, this has happened (like mentioned before) while just having Termux idle:

@V-no-A You should use logcat within ADB and not under Termux, as the latter will hide information about system activity.

P.S. On Pixel 5 with Android 12 it doesn't get suddenly killed.

[V-no-A]

@xeffyr I thought I used logcat within ADB. I ran adb logcat > logcat.txt on Windows and copied and pasted those several lines from the txt file. Can you point me to tutorial of how I am supposed to being doing this?

I ran adb logcat > logcat.txt on Windows

Then ok. But log is still too short, try capturing about 30 lines.

---

Btw, I'm running now overnight test for this issue, leaving Termux just opened with no utilities running except shell. Screen off, no wakelock, recent apps list cleared.

[agnostic-apollo]

Android 12 via 15755084 and updated via 5706277f has added a mechanism to monitor forked child processes started by apps and kills them if they consume too much CPU if app is in background.

Track the child processes that are forked by app processes

Apps could use Runtime.exec() to spawn child process and framework
will have no idea about its lifecycle. Now track those processes
whenever we find them - currently during the cpu stats sampling
they could be spotted. If it's consuming too much CPU while its
parent app process are also in the background, kill it.

By default we allow up to 32 such processes; the process with the
worst oom adj score of their parents will be killed if there are
too many of them.

Check PhantomProcessList commit history here. The Trimming phantom processes log entry is from here.

Basically, not a Termux issue and users upgrading to android 12 should expect killing of background processes even from AOSP, like OEM crazy killing wasn't enough.

When you detect the killing, you can run adb logcat -d > logcat.txt to dump the entire logcat buffer instead of starting realtime monitoring. And are you sure you are not starting some other processes, like a sshd daemon, etc or something else, check ps -ef.

[V-no-A]

Then ok. But log is still too short, try capturing about 30 lines.

Will do.

Btw, I'm running now overnight test for this issue, leaving Termux just opened with no utilities running except shell. Screen off, no wakelock, recent apps list cleared.

I think I always had at least 2 other apps in my recent list.

When you detect the killing, you can run adb logcat -d > logcat.txt to dump the entire logcat buffer instead of starting realtime monitoring.

Thanks for that. Is it advisable to share the whole logcat or should I actually spend several minutes going through and remove lines that might contain sensitive information?

And are you sure you are not starting some other processes, like a sshd demon, etc or something else, check ps -ef.

All I use Termux for is to run Python scripts inside my downloads directory. Here is that message after running ps -ef and while having 7 other apps opened in the background with the screen turned off (several minutes passed between running ps -ef and receiving that message):

[agnostic-apollo]

I haven't looked much at the code, but it seems that 32 process limit may be for phantom processes of all apps combined, so termux processes may get killed even if other apps have background processes running. But even if the limit were to be per app, then even then, termux would still be limited to max 32 processes, which may get killed anytime android decides.

Post output of following to see if there are other phantom processes running. What are your other apps doing?

adb shell "/system/bin/dumpsys activity settings | grep max_phantom_processes"
adb shell "/system/bin/dumpsys activity processes -a"

Or if you want to run from inside termux, first grant one time permissions over adb. You will require github actions debug build, or wait till v0.118 is released. PACKAGE_USAGE_STATS was recently requested via 865f29d, DUMP was available in v0.109.

adb shell pm grant com.termux android.permission.PACKAGE_USAGE_STATS
adb shell pm grant com.termux android.permission.DUMP

then run

/system/bin/dumpsys activity settings | grep max_phantom_processes
/system/bin/dumpsys activity processes -a

The -a flag minimizes the output. The ActivityManagerService dumps phantom processes list and it should show entries for All Active App Child Processes and All Zombie App Child Processes.

$ adb shell "/system/bin/dumpsys activity settings | grep max_phantom_processes"
  max_phantom_processes=32

$ adb shell "/system/bin/dumpsys activity processes -a"
...
All Active App Child Processes:
    proc #0: PhantomProcessRecord {747692e 7216:6914:bash/u0a147}
      user #0 uid=10147 pid=7216 ppid=6914 knownSince=-29m34s22ms killed=false
      lastCpuTime=20 timeUsed=+30ms oom adj=0 seq=16

I can reproduce the issue by running following. Sometimes termux gets killed as soon as I run the loop while its still in foreground, sometimes when I switch to another app and come back, and sometimes takes a few minutes. The frequency of sampling for the processes usage is likely the cause, considering that All Active App Child Processes does not get updated quickly.

for i in $(seq 40); do
sha256sum /dev/zero &
done

You can monitor cpu usage with top command and run killall sha256sum to kill the processes started.

Basically, unless this is somehow fixed or exempted, this would be like the end of termux (and tasker) or at least will be very unreliable. This should be reported to google since this is just crazy, possibly crazier than OEM killing.

Edit: It also happens with battery optimizations disabled for termux, don't see any related code either. Adaptive battery disabled too.

dumpsys activity processes log

  All Active App Child Processes:
    proc #0: PhantomProcessRecord {304e913 12355:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12355 ppid=6914 knownSince=-12s230ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #1: PhantomProcessRecord {fcd3750 12356:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12356 ppid=6914 knownSince=-12s230ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #2: PhantomProcessRecord {91b1d49 12357:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12357 ppid=6914 knownSince=-12s229ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #3: PhantomProcessRecord {2ede64e 12358:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12358 ppid=6914 knownSince=-12s229ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #4: PhantomProcessRecord {9cb036f 12359:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12359 ppid=6914 knownSince=-12s229ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #5: PhantomProcessRecord {d56787c 12360:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12360 ppid=6914 knownSince=-12s229ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #6: PhantomProcessRecord {26f4505 12361:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12361 ppid=6914 knownSince=-12s229ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #7: PhantomProcessRecord {746195a 12362:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12362 ppid=6914 knownSince=-12s229ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #8: PhantomProcessRecord {a2e678b 12363:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12363 ppid=6914 knownSince=-12s229ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #9: PhantomProcessRecord {9d0a068 12364:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12364 ppid=6914 knownSince=-12s229ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #10: PhantomProcessRecord {7242c81 12365:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12365 ppid=6914 knownSince=-12s229ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #11: PhantomProcessRecord {cbc7126 12366:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12366 ppid=6914 knownSince=-12s229ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #12: PhantomProcessRecord {19f167 12367:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12367 ppid=6914 knownSince=-12s229ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #13: PhantomProcessRecord {f435b14 12368:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12368 ppid=6914 knownSince=-12s228ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #14: PhantomProcessRecord {ae60fbd 12369:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12369 ppid=6914 knownSince=-12s228ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #15: PhantomProcessRecord {5ee79b2 12370:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12370 ppid=6914 knownSince=-12s228ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #16: PhantomProcessRecord {14a3d03 12371:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12371 ppid=6914 knownSince=-12s228ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #17: PhantomProcessRecord {e851480 12372:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12372 ppid=6914 knownSince=-12s228ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #18: PhantomProcessRecord {5e8eab9 12373:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12373 ppid=6914 knownSince=-12s228ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #19: PhantomProcessRecord {fc67efe 12374:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12374 ppid=6914 knownSince=-12s228ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #20: PhantomProcessRecord {8a9a65f 12375:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12375 ppid=6914 knownSince=-12s228ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #21: PhantomProcessRecord {d66f8ac 12376:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12376 ppid=6914 knownSince=-12s228ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #22: PhantomProcessRecord {5a47975 12377:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12377 ppid=6914 knownSince=-12s228ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #23: PhantomProcessRecord {9878d0a 12378:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12378 ppid=6914 knownSince=-12s228ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #24: PhantomProcessRecord {b6c497b 12379:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12379 ppid=6914 knownSince=-12s228ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #25: PhantomProcessRecord {ba0f398 12380:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12380 ppid=6914 knownSince=-12s227ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #26: PhantomProcessRecord {d5037f1 12381:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12381 ppid=6914 knownSince=-12s227ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #27: PhantomProcessRecord {1996fd6 12382:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12382 ppid=6914 knownSince=-12s227ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #28: PhantomProcessRecord {3ec0257 12383:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12383 ppid=6914 knownSince=-12s227ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #29: PhantomProcessRecord {a7db144 12384:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12384 ppid=6914 knownSince=-12s227ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #30: PhantomProcessRecord {21f622d 12385:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12385 ppid=6914 knownSince=-12s227ms killed=false
      lastCpuTime=0 oom adj=0 seq=48
    proc #31: PhantomProcessRecord {314b362 12386:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=12386 ppid=6914 knownSince=-12s227ms killed=false
      lastCpuTime=0 oom adj=0 seq=48

  All Zombie App Child Processes:
    proc #0: PhantomProcessRecord {244efbb 11686:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=11686 ppid=6914 knownSince=-10m12s335ms killed=true
      lastCpuTime=0 oom adj=0 seq=45
    proc #1: PhantomProcessRecord {98b26d3 11827:6914:sha256sum/u0a147}
      user #0 uid=10147 pid=11827 ppid=69

Is it advisable to share the whole logcat or should I actually spend several minutes going through and remove lines that might contain sensitive information?

Well that is the question. Its advisable to review it first, but one may not always know what's sensitive.

[agnostic-apollo]

So based on device_config shell command for the activity_manager namespace and max_phantom_processes key, which when updated, triggers PhantomProcessList.trimPhantomProcessesIfNecessary(), you can change the behaviour and it might be possible to disable it entirely based on the for loop in source code by setting max_phantom_processes to Integer.MAX_VALUE (2147483647). The setting seemed to survive on reboot but after a while got set back to default 32 and termux bash got killed, but maybe it normally resets after reboot, so I set it again. I haven't tested much if it actually works, but seems to be working, but needs more testing, someone should do it on a real device. If it keeps resetting, then that may be a problem. Not sure what (harm) adb shell "/system/bin/device_config set_sync_disabled_for_tests persistent" would do, it disables syncing, as per modes and used by tests and prevents setting all configs, added in ad3d45a. State can be checked with adb shell "/system/bin/device_config is_sync_disabled_for_tests".

# set value
adb shell "/system/bin/device_config put activity_manager max_phantom_processes 2147483647"

# get value
adb shell "/system/bin/dumpsys activity settings | grep max_phantom_processes"
# or (will be null initially)
adb shell "/system/bin/device_config get activity_manager max_phantom_processes"

Edit: As per below comment, this will only help prevent trimming, processes using excessive CPU will still get killed.

Btw, I'm running now overnight test for this issue, leaving Termux just opened with no utilities running except shell.

Everything went ok, Termux is not killed (expected).

Device info:

Application version:
0.117-gda6174e
Packages CPU architecture:
aarch64
Subscribed repositories:
# sources.list
deb https://termux.astra.in.ua/apt/termux-main stable main
Updatable packages:
pcre2/stable 10.39 aarch64 [upgradable from: 10.38]
Android version:
12
Kernel build information:
Linux localhost 4.19.191-gc2161d44afae-ab7624114 #1 SMP PREEMPT Mon Aug 9 09:02:05 UTC 2021 aarch64 Android
Device manufacturer:
Google
Device model:
Pixel 5

[agnostic-apollo]

Don't see any additional changes in android12-release branch and I'm using latest avd image sdk_gphone64_x86_64-userdebug 12 SE1A.211012.001 7818354 dev-keys, which has Nov 5, 2021 patch. Official releases build tags are here.

For more proof its happening, posting detailed info below.

Note that bash was started with pid 5683 and logcat logs the killing.

I ActivityManager: Killing PhantomProcessRecord {9ccd0ab 5683:5641:bash/u0a147}: Trimming phantom processes
I libprocessgroup: Successfully killed process cgroup uid 10147 pid 5683 in 0ms
I ActivityManager: Process PhantomProcessRecord {9ccd0ab 5683:5641:bash/u0a147} died

Transcript to start 1 bash process + 40 sha256sum processes

~ $ ps -ef
UID        PID  PPID  C STIME TTY          TIME CMD
u0_a147   5641   340  5  1970 ?        00:00:02 com.termux
u0_a147   5683  5641  0  1970 pts/0    00:00:00 /data/data/com.termux/files/usr/bin/bash
u0_a147   5728  5683  1  1970 pts/0    00:00:00 ps -ef
~ $ for i in $(seq 40); do sha256sum /dev/zero & done
[1] 5731
[2] 5732
[3] 5733
[4] 5734
[5] 5735
[6] 5736
[7] 5737
[8] 5738
[9] 5739
[10] 5740
[11] 5741
[12] 5742
[13] 5743
[14] 5744
[15] 5745
[16] 5746
[17] 5747
[18] 5748
[19] 5749
[20] 5750
[21] 5751
[22] 5752
[23] 5753
[24] 5754
[25] 5755
[26] 5756
[27] 5757
[28] 5758
[29] 5759
[30] 5760
[31] 5761
[32] 5762
[33] 5763
[34] 5764
[35] 5765
[36] 5766
[37] 5767
[38] 5768
[39] 5769
[40] 5770
~ $
[Process completed (signal 9) - press Enter]

Logcat showing 9 phantom processes trimmed

I ActivityManager: Killing PhantomProcessRecord {9ccd0ab 5683:5641:bash/u0a147}: Trimming phantom processes
I ActivityManager: Killing PhantomProcessRecord {30b2308 5731:5641:sha256sum/u0a147}: Trimming phantom processes
I ActivityManager: Killing PhantomProcessRecord {9a8aa1 5732:5641:sha256sum/u0a147}: Trimming phantom processes
I libprocessgroup: Successfully killed process cgroup uid 10147 pid 5683 in 0ms
I ActivityManager: Killing PhantomProcessRecord {19044c6 5733:5641:sha256sum/u0a147}: Trimming phantom processes
I ActivityManager: Killing PhantomProcessRecord {685cc87 5734:5641:sha256sum/u0a147}: Trimming phantom processes
I libprocessgroup: Successfully killed process cgroup uid 10147 pid 5731 in 0ms
I ActivityManager: Killing PhantomProcessRecord {2b367b4 5735:5641:sha256sum/u0a147}: Trimming phantom processes
I libprocessgroup: Successfully killed process cgroup uid 10147 pid 5732 in 0ms
I ActivityManager: Killing PhantomProcessRecord {9342fdd 5736:5641:sha256sum/u0a147}: Trimming phantom processes
I libprocessgroup: Successfully killed process cgroup uid 10147 pid 5733 in 0ms
I ActivityManager: Killing PhantomProcessRecord {3bbe752 5737:5641:sha256sum/u0a147}: Trimming phantom processes
I libprocessgroup: Successfully killed process cgroup uid 10147 pid 5734 in 0ms
I ActivityManager: Killing PhantomProcessRecord {2e8aa23 5738:5641:sha256sum/u0a147}: Trimming phantom processes
I libprocessgroup: Successfully killed process cgroup uid 10147 pid 5735 in 0ms
I libprocessgroup: Successfully killed process cgroup uid 10147 pid 5736 in 0ms
I libprocessgroup: Successfully killed process cgroup uid 10147 pid 5737 in 0ms
I libprocessgroup: Successfully killed process cgroup uid 10147 pid 5738 in 0ms
I ActivityManager: Process PhantomProcessRecord {9ccd0ab 5683:5641:bash/u0a147} died
I ActivityManager: Process PhantomProcessRecord {2e8aa23 5738:5641:sha256sum/u0a147} died
I init    : Untracked pid 5738 received signal 9
I ActivityManager: Process PhantomProcessRecord {9342fdd 5736:5641:sha256sum/u0a147} died
I ActivityManager: Process PhantomProcessRecord {685cc87 5734:5641:sha256sum/u0a147} died
I ActivityManager: Process PhantomProcessRecord {19044c6 5733:5641:sha256sum/u0a147} died
I init    : Untracked pid 5734 received signal 9
I init    : Untracked pid 5736 received signal 9
I init    : Untracked pid 5733 received signal 9
I ActivityManager: Process PhantomProcessRecord {30b2308 5731:5641:sha256sum/u0a147} died
I init    : Untracked pid 5731 received signal 9
I ActivityManager: Process PhantomProcessRecord {9a8aa1 5732:5641:sha256sum/u0a147} died
I ActivityManager: Process PhantomProcessRecord {2b367b4 5735:5641:sha256sum/u0a147} died
I ActivityManager: Process PhantomProcessRecord {3bbe752 5737:5641:sha256sum/u0a147} died
I init    : Untracked pid 5732 received signal 9
I init    : Untracked pid 5735 received signal 9
I init    : Untracked pid 5737 received signal 9

Remaining 32 tracked phantom processes

  All Active App Child Processes:
    proc #0: PhantomProcessRecord {c1b29f4 5739:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5739 ppid=5641 knownSince=-56s278ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #1: PhantomProcessRecord {511651d 5740:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5740 ppid=5641 knownSince=-56s278ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #2: PhantomProcessRecord {6a51392 5741:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5741 ppid=5641 knownSince=-56s278ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #3: PhantomProcessRecord {52c0163 5742:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5742 ppid=5641 knownSince=-56s277ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #4: PhantomProcessRecord {1baf160 5743:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5743 ppid=5641 knownSince=-56s277ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #5: PhantomProcessRecord {2643619 5744:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5744 ppid=5641 knownSince=-56s277ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #6: PhantomProcessRecord {d7cd6de 5745:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5745 ppid=5641 knownSince=-56s277ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #7: PhantomProcessRecord {55350bf 5746:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5746 ppid=5641 knownSince=-56s277ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #8: PhantomProcessRecord {9cdc38c 5747:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5747 ppid=5641 knownSince=-56s277ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #9: PhantomProcessRecord {8791ad5 5748:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5748 ppid=5641 knownSince=-56s277ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #10: PhantomProcessRecord {77b82ea 5749:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5749 ppid=5641 knownSince=-56s277ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #11: PhantomProcessRecord {c7639db 5750:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5750 ppid=5641 knownSince=-56s277ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #12: PhantomProcessRecord {e598c78 5751:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5751 ppid=5641 knownSince=-56s277ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #13: PhantomProcessRecord {1bd8f51 5752:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5752 ppid=5641 knownSince=-56s277ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #14: PhantomProcessRecord {906e3b6 5753:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5753 ppid=5641 knownSince=-56s277ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #15: PhantomProcessRecord {61498b7 5754:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5754 ppid=5641 knownSince=-56s276ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #16: PhantomProcessRecord {1d6f824 5755:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5755 ppid=5641 knownSince=-56s276ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #17: PhantomProcessRecord {7facf8d 5756:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5756 ppid=5641 knownSince=-56s276ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #18: PhantomProcessRecord {5158542 5757:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5757 ppid=5641 knownSince=-56s276ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #19: PhantomProcessRecord {bd00953 5758:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5758 ppid=5641 knownSince=-56s276ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #20: PhantomProcessRecord {39d7290 5759:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5759 ppid=5641 knownSince=-56s276ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #21: PhantomProcessRecord {e51d789 5760:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5760 ppid=5641 knownSince=-56s276ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #22: PhantomProcessRecord {57ab38e 5761:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5761 ppid=5641 knownSince=-56s276ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #23: PhantomProcessRecord {5c7e7af 5762:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5762 ppid=5641 knownSince=-56s276ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #24: PhantomProcessRecord {f0f27bc 5763:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5763 ppid=5641 knownSince=-56s276ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #25: PhantomProcessRecord {ef76345 5764:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5764 ppid=5641 knownSince=-56s276ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #26: PhantomProcessRecord {bf27a9a 5765:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5765 ppid=5641 knownSince=-56s276ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #27: PhantomProcessRecord {4b54fcb 5766:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5766 ppid=5641 knownSince=-56s275ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #28: PhantomProcessRecord {18503a8 5767:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5767 ppid=5641 knownSince=-56s275ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #29: PhantomProcessRecord {8afeec1 5768:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5768 ppid=5641 knownSince=-56s275ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #30: PhantomProcessRecord {7eda666 5769:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5769 ppid=5641 knownSince=-56s275ms killed=false
      lastCpuTime=0 oom adj=0 seq=13
    proc #31: PhantomProcessRecord {1c71da7 5770:5641:sha256sum/u0a147}
      user #0 uid=10147 pid=5770 ppid=5641 knownSince=-56s275ms killed=false
      lastCpuTime=0 oom adj=0 seq=13

App and Device Info

Termux App Info

APP_NAME: Termux
PACKAGE_NAME: com.termux
VERSION_NAME: 0.117
VERSION_CODE: 117
UID: 10147
TARGET_SDK: 28
IS_DEBUGGABLE_BUILD: true
APK_RELEASE: Github
SIGNING_CERTIFICATE_SHA256_DIGEST: B6DA01480EEFD5FBF2CD3771B8D1021EC791304BDD6C4BF41D3FAABAD48EE5E1

Device Info

Software

OS_VERSION: 5.10.43-android12-9-00031-g02d62d5cece1-ab7792588
SDK_INT: 31
RELEASE: 12
ID: SE1A.211012.001
DISPLAY: sdk_gphone64_x86_64-userdebug 12 SE1A.211012.001 7818354 dev-keys
INCREMENTAL: 7818354
SECURITY_PATCH: 2021-11-05
IS_DEBUGGABLE: 1
IS_EMULATOR: 1
IS_TREBLE_ENABLED: true
TYPE: userdebug
TAGS: dev-keys

Hardware

MANUFACTURER: Google
BRAND: google
MODEL: sdk_gphone64_x86_64
PRODUCT: sdk_gphone64_x86_64
BOARD: goldfish_x86_64
HARDWARE: ranchu
DEVICE: emulator64_x86_64_arm64
SUPPORTED_ABIS: x86_64, arm64-v8a

Everything went ok, Termux is not killed (expected).

What's the output for adb shell "/system/bin/dumpsys activity settings | grep max_phantom_processes" and your build tag. Maybe changes were made for pixel device releases. Moreover, revision branches don't exist in aosp repo.