RocketChat
bug: excessive cold startup time on each fresh app launch
Describe the Bug
A fresh (cold) start of the app takes an excessive amount of time to proceed. The app hangs on the splash screen for multiple seconds (best case ~8 seconds, worst case ~20 seconds).
Steps to Reproduce
- Ensure that the app is not running in the background. (Either kill it from the task manager or force stop via app's settings).
- Start the app.
Expected Behavior
The app should not hang for multiple seconds on the splash screen after a fresh start.
Actual Behavior
The app hangs for multiple seconds on the splash screen (after a fresh start).
Rocket.Chat Server Version
(not related to any server)
Rocket.Chat App Version
4.59.0
Device Name
Pixel 6
OS Version
Android 15
Additional Context
The issue already happens after a fresh install without even being logged into a server.
I attached two log files, in both cases the app hangs on the following log line:
<MMKV.cpp:207::initializeMMKV> root dir: /data/user/0/chat.rocket.android/files/mmkv.
The app stops hanging after the line which happens in the best case after 8 seconds, but sometimes it takes even 20 seconds to proceed:
<MemoryFile.cpp:97::open> open fd[0xb9], /data/user/0/chat.rocket.android/files/mmkv/default
rocketchat_startup_8seconds.log rocketchat_startup_20seconds.log
I observed the same behavior on other device models and android versions as well, such as:
- Samsung Galaxy A16 5G, Android 14
- Pixel 6a, Android 15
However, the following devices aren't affected by the very long startup time:
- Pixel 3a, Android 12: rocketchat_startup_pixel3a.log
- Pixel 4a, Android 13: rocketchat_startup_pixel4a.log
We are migrating to another mmkv library and expecting it to improve the startup time.
Will remind you once https://github.com/RocketChat/Rocket.Chat.ReactNative/pull/6744 get merged :)
We are migrating to another mmkv library and expecting it to improve the startup time.
Will remind you once #6744 get merged :)
It merged @matejbart are you facing issue now? I checked and didn't face any delay
It is merged but release is pending...
I checked locally didn't get any delay
We are migrating to another mmkv library and expecting it to improve the startup time. Will remind you once #6744 get merged :)
It merged @matejbart are you facing issue now? I checked and didn't face any delay
If you can provide a preview/test APK, I’m happy to test it for you.
You can download the apk from https://github.com/RocketChat/Rocket.Chat.ReactNative/pull/6846#issuecomment-3657738674
Thx, I tested the experimental version 4.68.0.107856 with all affected android devices and there is no longer any long delay at the app's startup.
Just for documentation purposes:
I also tested with the current live version 4.67.1.107769 which now only affects my two devices Pixel 6 and Pixel 6a (with the most recent Nov 2025 OS update).
Thx, I tested the experimental version
4.68.0.107856with all affected android devices and there is no longer any long delay at the app's startup.Just for documentation purposes: I also tested with the current live version
4.67.1.107769which now only affects my two devicesPixel 6andPixel 6a(with the most recent Nov 2025 OS update).
I too checked on pixel 6.. but on emulator. can you please share the video if possible so that I can try to reproduce and work on it further...
Sure, I made a video with my Pixel 6 device for both versions:
v4.67.1.107769
https://github.com/user-attachments/assets/0ffe152e-27ee-4a28-b6a9-a74aae24846c
v4.68.0.107856
https://github.com/user-attachments/assets/370da9a2-4234-40ae-82c5-d9ee7ebe9a97
It seems the issue is fixed but I will keep the issue open until we make 4.68.0 store release and you test the same on it :)