Partial Matching

Partial matching is a new feature in cross-seed v6, designed to capture torrents that are similar but may lack minor files, like .nfo, .srt, or sample files. This method allows you to seed more torrents across multiple trackers without needing to have all files.

The key technology that unlocks partial matching is linking files, which lets you seed two torrents that share a big file like an mkv, while also keeping their own separate copies of small files that don't match each other.

So, what's the outcome?

• More Matches: Partial matching finds torrents even when small files are missing/mismatched often doubling the amount of cross seeds found. Using this mode will find all possible cross seeds from your data.
• Fewer Wasted Snatches: Many torrents that can't match under matchMode: "safe" (due to a "technicality") can and will match with partial matching, meaning the snatch doesn't go to waste.

tip

Combine partial matching with seasonFromEpisodes to cross seed season packs even if you're missing individual episodes!

How Partial Matching Works

Partial matching relies on a new matchMode setting called partial. This mode only requires some files to match instead of all. cross-seed uses the fuzzySizeThreshold to set a minimum size for partial matches (default 0.02, allowing up to 2% size variance).

If a partial match is found, cross-seed will:

1. Inject the torrent with the matched files.
2. Recheck the torrent for missing files.
3. Resume according to autoResumeMaxDownload

Note

Nearly all partial matches will have the existing files at 99.9% instead of 100% after rechecking. This is expected and is due to how torrent piece hashing works.

Configuration Steps for Partial Matching

To enable partial matching, follow these three simple steps:

1. Enable linking

   Follow the instructions in the linking guide to set up linking.

2. Set matchMode to partial

   Enable partial matching by setting the matchMode option to partial.

   module.exports = {
   	// ... other settings ...
   	matchMode: "partial",
   };

That's it! If you want to further customize partial matching, you can adjust the fuzzySizeThreshold and autoResumeMaxDownload options depending on whether you are willing to incur more or less DL on partial matches.

tip

You can avoid downloading the same missing data on multiple trackers by following these steps