Repeated torrent uploads

 

I often, in fact, very often, see the same file uploaded into PirateBay by the same uploader?

Yes. That is quite common on The Pirate Bay, and there are several reasons you may encounter what appears to be the same file repeatedly uploaded by the same uploader.

One common reason is simply re-uploading. A torrent can disappear because it loses seeders, becomes corrupted, or is removed from the site. The uploader may create a new torrent pointing to the same underlying file. If the file itself hasn't changed, the torrent's contents can be identical even though the torrent entry is new.

Another is different packaging. An uploader may put the same movie, program, or collection into several torrents—perhaps one as a single file, another in a collection, another with subtitles, or with a different compression. From the filename it can look like duplication even when the torrent's contents differ slightly.

There is also a particularly interesting possibility: torrent files are identified by their info hash, which is calculated from the torrent's metadata. If two torrents have exactly the same torrent metadata, they have the same hash and are, in effect, the same torrent. But an uploader can make a new torrent containing the identical payload while changing the torrent metadata, producing a different hash. So you can genuinely have two different torrent entries that deliver byte-for-byte identical files.

And sometimes it is simply deliberate redundancy. An uploader may repeatedly seed popular material because older torrents have lost their seeders. From the user's point of view, it looks like, "Why on earth is this person uploading the same thing again?" From the uploader's point of view, it may be an attempt to keep the material available.

If what you're noticing is that the exact same uploader seems to have dozens of entries with precisely the same filename and size, that's a slightly different phenomenon, and I'd be curious about that pattern.

The most common pattern is identical file (same size and description) uploaded within a few minutes of each other. I assume there was some problem with the first so I go with the second.

Yes, that is a very reasonable interpretation.

If the same uploader posts the same file, same size, and same description within a few minutes, I would suspect the first torrent had some problem—most likely an error in the torrent creation or upload process, or the uploader discovered something wrong immediately afterward.

Your practice of taking the later one is sensible. The second upload may simply be a replacement, while the first was left on the site because the uploader couldn't or didn't remove it.

There is one caveat: identical size and description don't prove identical contents. The decisive identifier would be the torrent's info hash. If the hashes differ, they are technically different torrents even if they contain exactly the same file. If the hashes are identical, the two entries are essentially pointing to the same torrent.

And your observation that the replacement appears only a few minutes later makes accidental duplication much less likely than a deliberate "that one didn't work; try this one" re-upload.