John Williams wrote: > On Mon, Dec 1, 2014 at 4:15 PM, Alex Elsayed <eternaleye@xxxxxxxxx> wrote: >> There's a thing called the transitive property. When CRC32 is faster than >> SpookyHash and CityHash (while admittedly weaker), and SHA-1 on SPARC is >> faster than CRC32, there are comparisons that can be made. > > And yet you applied the transitive property with poor assumptions and > in a convoluted way to come up with an incorrect conclusion. > > >> It's that the flat assertion that "CityHash/SpookyHash/etc is always >> faster" is _unwarranted_, as hardware acceleration _has a huge effect_. > > Actually, the assertion is true and backed up by evidence that I > cited. I'm not sure why you think hardware acceleration only helps > SHA-1 and does not help CityHash or SpookyHash. ...because the hardware acceleration is in the form of instructions like "Update SHA1 state" ? https://software.intel.com/en-us/articles/intel-sha-extensions https://www.element14.com/community/servlet/JiveServlet/previewBody/41836-102-1-229511/ARM.Reference_Manual.pdf (page 99, the SHA1{C,P,M,H,SU0,SU1} instructions) On SPARC it's a full-on crypto coprocessor. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
