Using Flume
User Guide
Adding torrents
Magnet links. Paste into the add box, or copy one and let Flume notice: the add sheet detects a magnet on the clipboard and offers it. Verified on macOS, Windows and Linux.
Magnet links resolve their metadata over the DHT, so the status indicator must read Ready first. A magnet added while Connecting will sit waiting.
.torrent files. Use the file picker, or drag the file anywhere onto the
window — Flume highlights the drop target and opens the add dialog with it.
Non-torrent files are ignored rather than reported as an error.
Clipboard. If you have a magnet link on your clipboard when you open the add dialog, Flume prefills it. The clipboard is read only at that moment, when you have deliberately opened the dialog — never in the background.
Selecting files
Each torrent has a file tree with checkboxes. Deselected files are not downloaded.
This matters for distro torrents, which often bundle several ISO variants plus checksum files when you want one image.
Controlling torrents
| Action | Effect |
|---|---|
| Pause | Stops transfer, keeps the torrent |
| Resume | Restarts transfer from existing progress |
| Remove | Removes from the list, asks whether to delete files |
| Open folder | Reveals the download in your file manager |
Removal always asks before deleting data. Deleting a partially downloaded ISO by accident is a bad afternoon.
Settings
| Setting | Notes |
|---|---|
| Download folder | Where completed and in-progress files go |
| Rate limits | Global, plus per-torrent overrides |
| Max active torrents | Limits concurrent transfers |
| Listen port | Default 42221 |
| UPnP | Automatic router port forwarding |
| DHT | Required for magnet links |
| Theme | Light, dark, or follow system |
Looking at one torrent
Select a torrent and choose Open details for the inspector. The overview tab answers a question the list cannot: not “is this downloading” but “will this finish”.
Swarm health
The health column carries a word, never a colour alone.
| Reads | Means |
|---|---|
| Healthy | Every piece is held by several connected peers |
| Thin swarm | Every piece is held, but only just — losing a peer could strand it |
| No seeds | No connected peer holds some piece, so this cannot finish as it stands |
| Connected | Peers are connected but none has sent a bitfield yet, so there is nothing to judge from |
| Seeding | Complete, and serving peers |
| Idle | Paused, checking, or stopped on an error |
Connected is not a synonym for healthy. It means Flume does not know yet. Guessing between thin and healthy from the peer count alone would be a confident wrong answer: six peers who between them hold every piece will finish, and forty peers who all stopped at the same 6% will not.
The piece map
Two strips, stacked and sharing the same columns.
The upper strip is what you have: verified, in flight, not yet requested. Useful because overall progress hides shape — 60% with a solid head and an empty tail is downloading in order, and 60% scattered evenly is pulling rarest-first.
The lower strip is how many peers hold each region. It is the one that warns you: a tail that thins towards the right is a torrent heading for a stall. A region no peer holds is drawn full height in red, taller than anything else on the strip, and the caption says so.
It counts the peers you are connected to and does not count you, because the question it answers is whether the swarm can finish your download. Once a torrent is complete the strip disappears — the question is answered, and a finished torrent cannot stall.
What is limiting this download
Ranks the constraints Flume can actually measure and marks at most one as binding, with a sentence saying whether changing a setting would help.
- Your download cap — binding when you are hitting it. Raising it in Settings will help.
- Peer upload — binding when nothing on your machine is holding the transfer back, so the peers are. No setting will make this faster.
- Piece availability — binding when a piece is missing entirely. Nothing in Settings fixes that; it needs a peer holding the missing pieces to appear.
If nothing is binding, nothing is marked. A factor Flume cannot measure a ceiling for shows no bar and reads Not measured rather than an invented one.
Connection slots, disk write queue and hash-checking load are absent rather than estimated — the torrent engine does not report them, and a plausible number would be worse than none.
Seeding
Flume seeds completed torrents while running. Seeding requires an open listening port — see the firewall notes in Getting Started.
Seeding Linux ISOs back is genuinely useful; distro mirrors carry real bandwidth costs.
Troubleshooting
Slow or no download. Check the status indicator reads Ready. Check peer count — zero peers on a well-seeded torrent usually means a blocked port.
Torrent stuck at 99%. Usually a single rare piece. librqbit will keep trying; leave it running.
Downloads restart after a crash. Fast-resume state flushes on clean shutdown. If the app is killed hard, some re-hashing on next launch is expected — it verifies rather than re-downloads.