support/doc/redundancy.md

   1 # Redundancy
   2
   3 A PeerTube instance can cache other PeerTube videos to improve bandwidth of popular videos or small instances.
   4
   5 ## How it works
   6
   7 The instance administrator can choose between multiple redundancy strategies (cache trending videos or recently uploaded videos etc), set their maximum size and the minimum duplication lifetime.
   8 Then, they choose the instances they want to cache in `Manage follows -> Following` admin table.
   9
  10 <p align="center">
  11
  12 <img src="user/redundancy.png" alt="Redundancy" />
  13
  14 </p>
  15
  16 Videos are kept in the cache for at least `min_lifetime`, and then evicted when the cache is full.
  17
  18 When PeerTube chooses a video to duplicate, it imports all the resolution files (to avoid consistency issues) using their magnet URI and put them in the `storage.videos` directory.
  19 Then it sends a `Create -> CacheFile` ActivityPub message to other federated instances. This new instance is injected as [WebSeed](https://github.com/Chocobozzz/PeerTube/blob/develop/FAQ.md#what-is-webseed) in the magnet URI by instances that received this ActivityPub message.
  20
  21 ## Stats
  22
  23 See the `/api/v1/server/stats` endpoint. For example:
  24
  25 ```
  26 {
  27   ...
  28   "videosRedundancy": [
  29     {
  30       "totalUsed": 0,
  31       "totalVideos": 0,
  32       "totalVideoFiles": 0,
  33       "strategy": "most-views",
  34       "totalSize": 104857600
  35     },
  36     {
  37       "totalUsed": 0,
  38       "totalVideos": 0,
  39       "totalVideoFiles": 0,
  40       "strategy": "trending",
  41       "totalSize": 104857600
  42     },
  43     {
  44       "totalUsed": 0,
  45       "totalVideos": 0,
  46       "totalVideoFiles": 0,
  47       "strategy": "recently-added",
  48       "totalSize": 104857600
  49     }
  50   ]
  51 }
  52 ```