4 ms·

> However, it must be kept in mind that BLAKE3 is much faster than any other cryptographic hash only because it distributes the computation on all CPU cores. S

> However, it must be kept in mind that BLAKE3 is much faster than any other cryptographic hash only because it distributes the computation on all CPU cores. Surprisingly, this is incorrect. Here are some single-threaded measurements on a CPU with SHA-NI: https://bench.cr.yp.to/results-hash.html#amd64-icelake https://bench.cr.yp.to/results-hash.html#amd64-icelake. What you see there is that BLAKE3 can take better advantage of SIMD parallelism than other hashes, and the C and Rust library implementations do this by default. Multithreading isn't enabled by default in the library APIs, but if you do use it (and you have enough input to feed it) the benefits are multiplicative. The b3sum CLI does use multithreading by default. > only 1 cryptographic hash is faster: BLAKE3 SIMD implementations of KangarooTwelve are also about as fast as BLAKE3, given enough input.

adrian_b 4y ago
Those benchmark results might be caused by a very poor hardware implementation on Intel Ice Lake (the first Intel Core with SHA, neglecting Cannon Lake). In my tests on AMD Zen 3, BLAKE3 is much faster only when multi-threaded and that should be true on any CPU where the SHA instructions are well implemented. You are right that it is a little exaggerated to say that BLAKE3 is the only hash with these properties. Using a similar construction with BLAKE3 to allow parallel computation, instead of using the traditional Merkle–Damgård iterated construction, like SHA-1, SHA-2 and many others, it is possible to design many other fast hash algorithms and there already are many such experimental hashes. What I have meant was that BLAKE3 is, for now, the only one that has both a freely available and easy to install high-quality implementation, and it is based on a theory that has been studied long enough to have confidence in it. There are many other hashes that are candidates for being useful fast cryptographic hashes, but it is likely that a few more years are needed to trust them enough.

adrian_b 4y ago

Those benchmark results might be caused by a very poor hardware implementation on Intel Ice Lake (the first Intel Core with SHA, neglecting Cannon Lake). In my tests on AMD Zen 3, BLAKE3 is much faster only when multi-threaded and that should be true on any CPU where the SHA instructions are well implemented. You are right that it is a little exaggerated to say that BLAKE3 is the only hash with these properties. Using a similar construction with BLAKE3 to allow parallel computation, instead of using the traditional Merkle–Damgård iterated construction, like SHA-1, SHA-2 and many others, it is possible to design many other fast hash algorithms and there already are many such experimental hashes. What I have meant was that BLAKE3 is, for now, the only one that has both a freely available and easy to install high-quality implementation, and it is based on a theory that has been studied long enough to have confidence in it. There are many other hashes that are candidates for being useful fast cryptographic hashes, but it is likely that a few more years are needed to trust them enough.