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A comment on Maybe Skip SHA-3. Parent comment

Re:Maybe Skip SHA-3 by briansmith on Wednesday May 31, 2017 @03:51PM (#14455375)
I guess 32-bit x86 performance is maybe not the best benchmark. I think people aren't optimizing for that ISA to the same extent as they are optimizing for x86-64, 64-bit ARMv8, or 32-bit ARM.

If you care about performance and you don't have dedicated SHA-256 instructions then on a 64-bit platform you should evaluate SHA-512 as it is much faster. If you only have 256 bits of storage available then truncate its output to 256 bits. IIRC, it's about 1GB/sec on my Haswell laptop.

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Re:Maybe Skip SHA-3 by jasode on Wednesday May 31, 2017 @04:00PM (#14455445)
>I guess 32-bit x86 performance is maybe not the best benchmark.

I compiled for 32bit instead of 64bit because I wanted the same executable to also run on a 32bit Macbook. When Thomas Pornin ran benchmarks[1] in 2010 for both 32bit & 64bit, the SHA256 hash performance didn't change as much as the SHA512. I'll recompile for 64bit and report back if there was a massive difference.

[1] https://stackoverflow.com/questions/2722943/is-calculating-a...

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Re:Maybe Skip SHA-3 by baby on Wednesday May 31, 2017 @04:49PM (#14455791)
SHA-3 lanes are 64 bits. In 64 bits arch they can use full registers for operations. I'd bet it would be way faster on 64bit
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Re:Maybe Skip SHA-3 by npscalar on Monday June 05, 2017 @11:07AM (#14488116)
Mismatches can show an interesting property. It is likely that SHA-256 is slower than Keccak on 64-bit platforms, and that SHA-512 is slower than Keccak on 32-bit platform.
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