# Sync many files slow ? Android11
**URL:** https://forum.syncthing.net/t/sync-many-files-slow-android11/16397
**Category:** Android
**Created:** [February 24, 2021, 1:00pm UTC](https://forum.syncthing.net/t/sync-many-files-slow-android11/16397 "2021-02-24T13:00:53Z")
**Posts on this page:** 13
**Page:** 1
### Author:  [@banigithub](https://forum.syncthing.net/u/banigithub)
#### Post date: [February 24, 2021, 1:00pm UTC](https://forum.syncthing.net/t/sync-many-files-slow-android11/16397/1 "2021-02-24T13:00:53Z")
So I’ve go seven devices, on a variety of platforms (Win10, MacOS, Ubuntu20LTS, Android 10&11), all syncing a number of folders, one of which has upwards of 30k small files. It’s a Joplin source directory structure, so lots of markdown text files and a bunch of resource files of varying types. All of that works beautifully, apart from the Android 11 device, a Samsung Galaxy S20U 5g. It is running Syncthing-fork (I moved to fork as the stock version had the same issue and I wondered whether fork could resolve) at 1.12.n.
Symptom is that devices other than the Android 11 will sync the lot beautifully in a very normal period (couple of hours?); A11 has been running now for several days and still has ~25k files to sync (~620MiB). I’ve tried to get it working three previous times: stock syncthing 1.12 and 1.13; now with -fork 1.12, all with the same symptoms: the sync starts at ‘normal’ pace, and then gradually slows to effectively a standstill over a couple of few days. The most interesting comparison is of course between the Android 11 Samsung Galaxy S20U and the Samsung Galaxy S10 running Android 10. Both have identical folder structure and config / .stignore etc., but A11 runs as you’d expect. I’ve looked for anyone else apparently experiencing the same issue to no avail; I’ve seen of course the discussions over All File Storage, but this doesn’t appear to be directly related. Does anyone else have an Android 11 device syncing 25+k small files with no problem? If you do, I need to keep looking!
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### Author:  [@imsodin](https://forum.syncthing.net/u/imsodin)
#### Post date: [February 24, 2021, 2:14pm UTC](https://forum.syncthing.net/t/sync-many-files-slow-android11/16397/2 "2021-02-24T14:14:08Z")
Did you check the web UI for any clues/issues? And then in the next step logs?
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### Author:  [@banigithub](https://forum.syncthing.net/u/banigithub)
#### Post date: [February 25, 2021, 5:17am UTC](https://forum.syncthing.net/t/sync-many-files-slow-android11/16397/3 "2021-02-25T05:17:39Z")
Hi Simon, thanks for responding. I’ve been looking at the logs, but can’t see any obvious errors; things are happening, just appears slowly. As I write this, there are now ~17k files left (~455MiB), so maybe 8k files in 16 hours? As I say, there are all pretty small. Do you know which of the WebGUI ‘logging facilities’ would be mostly involved in this apparently extended ‘scanning/syncing’ phase? There’s quite a lot of this action: 15:15:52W/SyncthingNativeCode 2021/02/25 05:15:52 broadcastBeacon: Failed service ‘Service@0x40000485c0 created by broadcastBeacon@0x40001b60f0/writer’ (1.000000 failures of 2.000000), restarting: true, error: route ip+net: netlinkrib: permission denied
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### Author:  [@banigithub](https://forum.syncthing.net/u/banigithub)
#### Post date: [February 25, 2021, 5:38am UTC](https://forum.syncthing.net/t/sync-many-files-slow-android11/16397/4 "2021-02-25T05:38:06Z")
Seems to be going along at about 1 file every 2 seconds currently?
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### Author:  [@mmwelt](https://forum.syncthing.net/u/mmwelt)
#### Post date: [February 25, 2021, 5:44am UTC](https://forum.syncthing.net/t/sync-many-files-slow-android11/16397/5 "2021-02-25T05:44:03Z")
Could this be related to the changes that Samsung seems to have made in Android 11?
> **[Is Samsung aggressively killing backgrounds apps on Android 11?](https://www.sammobile.com/news/samsung-killing-background-apps-android-11-update/)**
>
> Samsung has done a pretty amazing job in rolling out the Android 11-based One UI 3.x update to its smartphones ...
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### Author:  [@banigithub](https://forum.syncthing.net/u/banigithub)
#### Post date: [February 25, 2021, 6:02am UTC](https://forum.syncthing.net/t/sync-many-files-slow-android11/16397/6 "2021-02-25T06:02:44Z")
Good call, but I don’t think so. I’ve certainly double checked that it is ‘Not optimised’.
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### Author:  [@AudriusButkevicius](https://forum.syncthing.net/u/AudriusButkevicius)
#### Post date: [February 25, 2021, 9:42am UTC](https://forum.syncthing.net/t/sync-many-files-slow-android11/16397/7 "2021-02-25T09:42:58Z")
Each file is fsynced after transfer, which might take a few seconds, so that might cause slowness if you have a lot of small files.
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### Author:  [@banigithub](https://forum.syncthing.net/u/banigithub)
#### Post date: [February 25, 2021, 11:02am UTC](https://forum.syncthing.net/t/sync-many-files-slow-android11/16397/8 "2021-02-25T11:02:14Z")
I wonder why there seems to be such a marked difference between the Android 10 Galaxy S10 and the Android 11 Galaxy S20? I should probably wipe the 10 and get a comparison. Anyway - appreciate you taking the time to think about it!
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### Author:  [@hb1547](https://forum.syncthing.net/u/hb1547)
#### Post date: [February 26, 2021, 10:46pm UTC](https://forum.syncthing.net/t/sync-many-files-slow-android11/16397/9 "2021-02-26T22:46:35Z")
I think I’m seeing this issue too on a Samsung Galaxy s10 after upgrading to Android 11. For me, it’s not the file transfer process that’s slow, but the scanning process.
I have a Send Only folder on my PC with ~10k files, 90 GB (MP3s) and a Receive Only folder on my phone’s SD card.
Each time SyncThing goes through the scanning process (which seems to be when starting the app and at the end of the transfer process), it takes around 20+ minutes. It takes longer if the app is in the background or if the device’s screen is off. Before updating, the process was relatively quick: probably 30 seconds or less.
In the logs, I see “Folder […] isn’t making sync progress - retrying in #m#ss”. Not sure where else to look for information.
My SyncThing app is not battery optimized either.
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### Author:  [@hb1547](https://forum.syncthing.net/u/hb1547)
#### Post date: [February 26, 2021, 11:05pm UTC](https://forum.syncthing.net/t/sync-many-files-slow-android11/16397/10 "2021-02-26T23:05:59Z")
I tried using a folder on my phone’s internal storage, and that doesn’t have the same issue as I described. Seems like it’s tied to the SD card storage. I haven’t found much on this, but this [Reddit comment](https://www.reddit.com/r/androiddev/comments/kpn68k/android_11_very_slow_file_access_performance/gizbd8t/) seems like a similar issue.
I’m not sure if I’m having the same issue as the OP.
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### Author:  [@banigithub](https://forum.syncthing.net/u/banigithub)
#### Post date: [February 28, 2021, 10:45pm UTC](https://forum.syncthing.net/t/sync-many-files-slow-android11/16397/11 "2021-02-28T22:45:35Z")
So I’m not using the SD card, but that discussion is really interesting - I’d not read that before. Feels like it could be the new security layer. Update is that the folder is now up to date, after several days; I guess I just have to hope that the files themselves are sufficiently static that keeping up to date is no drama.
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### Author:  [@leder11011](https://forum.syncthing.net/u/leder11011)
#### Post date: [March 5, 2021, 5:00pm UTC](https://forum.syncthing.net/t/sync-many-files-slow-android11/16397/12 "2021-03-05T17:00:44Z")
As you can see in the last comment w/ the screenshot of this post:
> [@Syncthing detects devices, but does not sync folders](https://forum.syncthing.net/t/syncthing-detects-devices-but-does-not-sync-folders/16373):
>
> I have syncthing w/: ubuntu box android smartphone added fw rule syncthing detects devices but does not sync my folders! Any idea? These are the ubuntu logs: I wanted to add my logs here, but the forum prevents me from doing so! [https://www.file-upload.net/download-14488640/syncthing\_syslog.txt.html](https://www.file-upload.net/download-14488640/syncthing_syslog.txt.html)
OP 8pro is my Android 11 smartphone!
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### Author:  [@system](https://forum.syncthing.net/u/system)
#### Post date: [April 4, 2021, 5:00pm UTC](https://forum.syncthing.net/t/sync-many-files-slow-android11/16397/13 "2021-04-04T17:00:57Z")
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