Caching and uploads
CloudMount never keeps a full copy of a drive on your device. It fetches what apps ask for and keeps some of it close by. How it does that is the main difference between the two platforms.
Android: a cache in front of the drive
Section titled “Android: a cache in front of the drive”On Android, rclone’s VFS layer sits between the Files app and the drive. CloudMount runs it in rclone’s full cache mode:
- Reading a file fetches the parts an app reads and keeps them in the cache, so seeking in a video or reopening a document doesn’t download it again.
- Saving a file writes it to the cache at local speed, then uploads it in the background. The cache holds it until the upload finishes, even if that takes days because of your upload rules.
- Validating: CloudMount checks cached data against the file’s size and modification time on the drive (or its checksum, where modification times aren’t reliable) before using it, and fetches it again if the file changed.
| Limit | Default | Setting |
|---|---|---|
| Cache size, per drive | 5 GB | Settings → Storage → Cache size limit, or per drive |
| Unused data kept for | 1 week | Settings → Storage → Keep cached files, or per drive |
| Free space left on the phone | 5% of storage, at most 1 GB | Not adjustable |
When the cache is full, the least recently used data goes first. Files waiting to upload are never evicted.
The cache lives in CloudMount’s cache folder, which Android may clear when storage is very low. Clear cache in CloudMount’s settings skips drives with uploads waiting, but clearing the app’s cache in Android’s own settings doesn’t, and can lose saves that haven’t uploaded yet.
Offline files are kept separately and aren’t evicted.
Freshness on Android
Section titled “Freshness on Android”Folder listings are cached for 30 seconds. After that, opening a folder lists it from the drive again, so changes made elsewhere appear within half a minute of opening the folder. CloudMount’s own changes appear at once.
Windows: real files that sync
Section titled “Windows: real files that sync”On Windows, there’s no separate cache. A drive’s folder in
%USERPROFILE%\CloudMount is the cache: opening a file downloads it into
place, and it stays there as an ordinary NTFS file.
- Reading an online-only file downloads it, progressively, into the folder. It then opens at local speed until you free up its space.
- Saving writes the real file in the folder. CloudMount notices the change and uploads it, with a queue that survives restarts.
- Freeing space is up to you or Windows: Free up space in Explorer or on the drive’s page, or Windows Storage Sense. There’s no size cap.
Freshness on Windows
Section titled “Freshness on Windows”Windows needs CloudMount to tell it about changes made elsewhere, so the sync engine looks for them actively: through the service’s change notifications where it has them, otherwise by re-listing recently used folders every few minutes and any folder you open. See Changes made elsewhere.
Side by side
Section titled “Side by side”| Android | Windows | |
|---|---|---|
| Where file data is kept | A cache inside the app | The drive’s folder in your profile |
| Size limit | 5 GB per drive by default | None; Storage Sense or Free up space |
| Opening a large video | Streams, with seeking | Downloads fully first while Defender scans it |
| Changes made elsewhere | Seen when a folder is reopened, after 30 s | Pushed or polled in the background |
| A save meets a change made elsewhere | The upload replaces the drive’s version; the in-app editor warns first | Both versions are kept |
| Keep files without a connection | Offline files (Pro) | Always keep on this device (Pro); opened files also stay |