Android 11 file system slowness accessing files on public storage [169259464]

WAI

Bug

[AOSP] assigned

Status Update

No update yet.

Description

mc...@navionics.com

created issue #1

Sep 24, 2020 07:24AM

Using c++ code compiled with ndk to access file system using cstdio standard IO functions, there is a significant performance problem since the file system is extremely slow when the application attempts to open/read/write files in the internal storage.

This issue looks to be introduced with Scoped Storage changes, in fact if the application attempts to access resources in the private application folder (path returned from getFilesDir(), i.e. /data/data/<app-bundle-id>/files) the issue is not present and file system APIs are well performing.

Using instead a path outside the app private storage, i.e. /sdcard/MyFolder it is noticed a significant performance degradation (it appears to be 10-15 times more slow then app private storage).
This issue has been observed by customers after having upgraded the Android OS on their Pixel 3 devices. Our application is a map / navigation app and we normally store data in the public folder and the rendering performances are very poor after the OS upgrade.

It is expected that upgrading the OS on a device, the application performances do not drastically decrease because of platform changes.

Comments

vi...@google.com <vi...@google.com> #2Sep 24, 2020 11:07AM

Assigned to vi...@google.com.

Information redacted by Android Beta Feedback.

vi...@google.com <vi...@google.com> #3Oct 1, 2020 01:02PM

Thank you for reporting this issue. We have shared this with our product and engineering team and will update this issue with more information as it becomes available.

mc...@navionics.com <mc...@navionics.com> #4Oct 1, 2020 04:34PM

Could you please let me know if without Android Auto usage and not using com.njm.njmsafedrivego and com.august.bennu lessen battery drain?

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vi...@google.com <vi...@google.com> #5Oct 5, 2020 12:51PM

Battery drain remain the same.

On Fri, Apr 4, 2025, 09:37 <buganizer-system@google.com> wrote:

- Show quoted text -

mc...@navionics.com <mc...@navionics.com> #6Oct 13, 2020 07:25AM

Could you please capture a bug report and share it here?

vi...@google.com <vi...@google.com> #7Oct 15, 2020 10:01AM

Please provide the requested information to proceed further. Unfortunately the issue will be closed within 7 days if there is no further update.

mc...@navionics.com <mc...@navionics.com> #8Oct 15, 2020 03:05PM

This will require a new app version, a behavioural change for the user and will simply hide the regression introduced with Android 11.

vi...@google.com <vi...@google.com> #9Oct 19, 2020 11:40AM

Some performance penalty is to expected since we intercept all file system operations to implement Scoped Storage, as mentioned here: https://source.android.com/devices/storage/scoped.

Using instead a path outside the app private storage, i.e. /sdcard/MyFolder it is noticed a significant performance degradation (it appears to be 10-15 times more slow then app private storage). This issue has been observed by customers after having upgraded the Android OS on their Pixel 3 devices. Our application is a map / navigation app and we normally store data in the public folder and the rendering performances are very poor after the OS upgrade.

getExternalFilesDir bypasses fuse to support this exact usecase. If the performance is from reading and writing individual files, moving to getExternalFilesDir is the only way to mitigate it for now. If it's scanning directories or bulk file operations, there may be ways to restructure the application code.

From our testing, we have not seen such big regression - so please give us more details.

ci...@gmail.com <ci...@gmail.com> #10Oct 20, 2020 11:46AM

I have provided a test application, if you run on a pixel device with android 11 you can get the evidence that running the same test case (writing and reading from 100 files) it takes 10/15 times more while performing operation on public storage.

[Deleted User] <[Deleted User]> #11Oct 22, 2020 09:52AM

Our applications also suffer from file i/o performance degradation since Android 11. With our test app (attached) we measured up to 35 times slow-down for create/delete operations and a 2-3 times slow-down for exist, get file length and get last modified.
The features of the apps require access to all files on the device so it is not possible to use only getExternalFilesDir location.

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vi...@google.com <vi...@google.com> #12Oct 27, 2020 02:11PM

Re-

Comment#11

, please upload the attachment to google drive folder and share the folder to android-bugreport@google.com, then share the link here. Thanks.

sb...@gmail.com <sb...@gmail.com> #13Oct 29, 2020 08:21AM

Here is the test app on Google drive

https://drive.google.com/file/d/1uG7cxf-yRaNO4LtfCKepkbyOBUPkjV45/view?usp=sharing

ci...@gmail.com <ci...@gmail.com> #14Feb 12, 2021 11:32AM

Any update on this issue?

vi...@google.com <vi...@google.com> #15
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Mar 15, 2021 09:41AM

Status: Won't Fix (Intended Behavior)

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vi...@google.com <vi...@google.com> #16Mar 15, 2021 09:43AM

If the data is not media that is intended to be shared with other apps, please use app-private storage, as suggested earlier. While Android currently allows you to read/write all over the /sdcard, once your app starts targeting API 30, it will no longer be allowed to.
If you do need this data to be shared, and it is media (eg images, videos), you can access this data through the MediaStore APIs (eg ContentResolver.openFileDescriptor(); the file descriptor returned from that APIs will also work directly on the lower filesystem, and should be fast

pa...@tomtom.com <pa...@tomtom.com> #17Mar 15, 2021 09:53AM

This is issue about external removable private storage as one can check in benchmark tests. Looks like FUSE mitigation is not applied correctly. Anyway I raised this issue also on Samsung support they supposedly looking into it but it takes them forever.

pa...@tomtom.com <pa...@tomtom.com> #18Mar 15, 2021 09:56AM

Sorry thought I was responding to https://issuetracker.google.com/u/3/issues/179412245

pl...@gmail.com <pl...@gmail.com> #19Mar 19, 2021 02:21PM

Play store does not install anything anymore. WTF people. Constantly pending, and I can't fix it without a degree in stupidity, because any smart company would make it possible to undo the last update.

fa...@gmail.com <fa...@gmail.com> #20Mar 25, 2022 10:14AM

2022 and this problem is still on

st...@planetcoops.com <st...@planetcoops.com> #21Apr 6, 2022 10:46AM

Re-Comment#20, apparently the awful performance degradation is intended behavior and won't be fixed. End users are upgrading their android devices to the "latest and greatest" and experiencing worse app performance than they had pre-Android 11 depending on their apps' use of scoped storage, for an example see https://somegadgetguy.com/2022/02/16/android-12-broke-all-my-benchmarks-scoped-storage-rant/

tl...@gmail.com <tl...@gmail.com> #22Apr 16, 2022 06:16PM

the issue prevent me from buying another android phone in the future

ke...@gmail.com <ke...@gmail.com> #23Aug 23, 2023 07:11PM

Any updates Google? Here I am on a brand new ultra-fast ROG Phone 7 and shared storage is performing like a floppy disk. It's not "Some performance penalty." It is totally unusable, totally broken slow.

I see you keep closing tickets about SAF preventing applications from working. Between this and Chrome Topics, you're making an excellent argument for nobody to ever touch the Google ecosystem again.