Syncthing v0.9.0 released

Important Notes

  • Not compatible with v0.8.x. Upgrade all nodes.

  • Upgrade manually. Syncthing v0.8 will not update automatically to Syncthing v0.9. Download the release from

  • The cluster needs to be upgraded as a unit. Syncthing v0.9 can not talk to syncthing v0.8.

  • Upgrade the cluster when it’s in sync. Syncthing v0.9 can’t read the index information from v0.8 and will need to reindex all files. To avoid the risk of conflicts, do this when the nodes are already in sync.

  • Your existing indexes and a backup copy of the configuration will be moved to a directory called backup-of-v0.8 in your config directory.

Notable Changes Since v0.8

  • GUI has been localized and is available in German, Greek, English, Spanish, French, Italian, Portuguese, Russian and Swedish; configure your browser to request your native language.

  • Memory usage for large repositories has been drastically reduced. Note that there’s no such thing as a free lunch and this comes at a slight performance and CPU usage cost. This work is not done, there are still situations where syncthing uses more memory than it should.

  • GUI is event driven. Having the GUI open on an otherwise idle node does not cause high CPU usage like it sometimes would in v0.8.

  • Protocol compression is changed from deflate to LZ4, reducing CPU cost significantly. Compression can be disabled on a per node basis in the GUI.

  • Upgrades to new versions can be performed directly in the GUI (unless disabled at build time, not yet supported on Windows).

  • Node ID format has been updated, check digits added for correctness validation.

  • Directory modification times are no longer synchronized (this might be reintroduced in the future).

  • When file versioning is in use, the .stversions directory is stored in the repository root only instead of spread out everywhere. This is not migrated on upgrade, manual cleanup of old .stversions directories will be necessary.

A bunch of minor bugs and annoyances have been fixed, and I’m sure new ones have been introduced.


Oh, it’s nice to get this out the door. Now I’m going to relax and watch the flood of new bug reports. :wink:

Works great on Linux x86_64, ARM v6 and OSX: Thank you!

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