On Mon, Dec 22, 2014 at 03:35:22PM -0800, Joe Stringer wrote: > Previously, when using the 128-bit hash in conjunction with the 32-bit > hash tables, we would ignore the upper 96 bits rather than attempting to > redistribute the hash across the 32-bit output space. This patch adds a > new function to translate the hash down from 128 bits to 32 bits for > this use case.
Suppose that we had 128-bit random numbers instead of 128-bit hashes. Then, if combining the 32-bit pieces of that random number gave us a higher-quality random 32-bit number than just taking any one 32-bit piece, it would mean that the random numbers weren't very random. By analogy, I think that this patch (without reading it) should only make a difference if the 128-bit hash isn't very high-quality. If so, it might be better to consider improving our 128-bit hash function, instead of the approach taken here. _______________________________________________ discuss mailing list discuss@openvswitch.org http://openvswitch.org/mailman/listinfo/discuss
