save 512 bytes of RAM#2562
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Instead of 64 bit fingerprints save 32 bit fingerprints We were at 128 / 2^64 we are now at 128 / 2^32 (1 in 33M) If we reduced it to 3 bytes (24 bits), we would have 1 in 131k.
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Instead of 64 bit fingerprints use 32 bit fingerprints for de-dupping. This saves us 512 bytes of RAM.
The probability of false positive was at 128 / 2^64, this would bring it to 128 / 2^32 (1 in 33M)
If we reduced it to 3 bytes (24 bits), we would have 1 in 131k at which point it may not longer be negligible at scale (but may still be acceptable);
On discord I was talking about probabilistic data structures (bloom/cuckoo filters); maybe we don't need the complexity, especially if there is no need to track more than 128 packets.