Overview
Using download priorities, you can control which files are downloaded first based on their modification time or other preferences. This feature is useful if you want, for example, newer files to sync before older ones.
Setting Download Priority
You can enable file download prioritization in the preferences of each share. Within the share preferences, you can choose to prioritize downloads either by file modification time or by file size. By default, no prioritization is enabled, and files are downloaded without any specific order.
Additionally, there is a global option folder_defaults.transfer_priority in the power user preferences where you can set a default download priority. When this is configured, the selected priority will automatically apply to all shares – both existing shares, with unchanged manually priority, and any new shares you create, including single file sharing.
Note: share with manually set priority in the Share Preferences is no longer affected by changes to transfer priority in the Power User Preferences — even if the priority was later manually set back to None.
How Prioritization Works
Only the active files in the queue are prioritized, up to a limit of 50,000 active files.
When a higher priority file is added to the queue, lower priority downloads are suspended to allow the higher priority file to download first. There are some internal exceptions to this suspension logic.
When a large file is being downloaded and a higher priority file appears, the current download will be suspended immediately, regardless of how little data remains to complete it. The system resumes download of the suspended file once it is again first in the queue.
If files inside the active download queue change, for example, it becomes bigger or smaller, or some files encounter errors , Sync will rebuild the current download queue accordingly. This may affect performance.
With file transfer prioritization rules still apply. The system uses the default priority from the power user settings for sending single files, and there is no way to change the priority once the file send process has started.
Limitations
Building a download queue on large dataset, especially if the dataset changes frequently, may cause mild performance degradation and slower synchronization speed.
If your download queue is already full (over 50k files) and higher priority files are waiting to be synced, they will not enter the queue until there is a slot available.
Currently, only files that are split in pieces during transfer, strictly follow the prioritization rules (check direct_torrent_enabled option in power user preferences). If there are files in prioritized download queue and a new non-splittable file with higher priority arrives, Sync will not cancel any active downloads.
In the user interface, the download queue is visible, but files may still appear listed alphabetically rather than in their actual priority order.