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Title: How much operations take SHA-2 ? Post by: Frodek on July 20, 2014, 02:55:36 PM Traditionally is conversion factor 12700 flops per hash/s. In Talk:FLOPS (https://en.wikipedia.org/wiki/Talk:FLOPS) :
Quote bitcoinwatch.com calculates PFLOPS of bitcoin network as: take number of Hashes/second (Terahashes/s of SHA256) and multiply by 12700 to get a "Single-precision FLOPS estimate". One hash calculation is considered as 6350 32-bit integer operations, and each integer operation is considered equal to two single-precision flops. Source of constants is: http://forum.bitcoin.org/index.php?topic=4689.0 (http://forum.bitcoin.org/index.php?topic=4689.0) (with reference to bincoinwatch's admin). Actual bitcoin mining contains no (or almost no) floating-point calculations. But I wonder: one 32 bit integer operation is counts as two floating point operations? While one floating point operation take longer tome than one integer operation.Second question: How compute 6350 operations while SHA of long data take long time and SHA of short data take short time? How long data must be digest compute? Title: Re: How much operations take SHA-2 ? Post by: Frodek on July 22, 2014, 07:46:51 AM Where can I find source of SHA implementation on CPU?
Title: Re: How much operations take SHA-2 ? Post by: shorena on July 22, 2014, 10:57:06 AM Wikipedia has pseudocode for sha256, rosettacode has several implementations and your favorite programming language has probably a libary for it.
rosettacode.org/wiki/SHA-256 |