On Thu, Nov 7, 2024 at 10:12 PM Jeremy Stanley <[email protected]> wrote: > [...] > > Probably the most convincing reason to replace such uses of MD5 is > that we collectively get to stop wasting time answering this same > question over and over and over...
One more datapoint that might be useful.... AMD/Intel, ARMv8 and PowerPC offer SHA-256 acceleration, so SHA-256 outperforms MD5 calculations. An Ice Lake machine: CRC-32C: 0.73 cpb MD5 - 5.5 cpb SHA256 - 2.6 cpb A Raptor Lake machine: CRC-32C - 0.12 cpb MD5 - 1.6 cpb SHA256 - 0.6 cpb An armv8+crypto machine (gcc117 from the Compile Farm) CRC-32C - 0.76 cpb MD5 - 6.3 cpb SHA256 - 2.7 cpb A POWER8 machine (gcc112 from the Compile Farm) CRC-32C - 8.2 cpb MD5 - 11.3 cpb SHA256 - 3.7 cpb In the mini table cpb is cycles-per-byte. The smaller the cpb the better. cpb takes processor speed out of the equation so you can compare algorithms across architectures. So if Debian is building lots of *.md5sum files, it might be useful to consider SHA-256. The calculations will be faster and use less energy. And if cryptographic properties are not needed, then switch to CRC-32C, which also has hardware acceleration and is even faster! Jeff
