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b1c8f88a44
We've had weak/rolling hashing in the code for quite a while. It was a popular request for a while, based on the belief that rsync does this and we should too. However, the benefit is quite small; we save on average about 0.8% of transferred blocks over the population as a whole: <img width="974" alt="Screenshot 2025-03-28 at 17 09 02" src="https://github.com/user-attachments/assets/bbe10dea-f85e-4043-9823-7cef1220b4a2" /> This would be fine if the cost was comparably low, however the downside of attempting rolling hash matching is that we (by default) do a complete file read on the destination in order to look for matches before we starting pulling blocks for the file. For any larger file this means a sometimes long, I/O-intensive pause before the file starts syncing, for usually no benefit. I propose we simply rip off the bandaid and save the effort.