Hi everyone. I'm still reading CRUSH source code. When reading src/crush/hash.c, I've got some questions about the hash function. 1. There are several magic numbers there, like 1315423911, 231232, 1232. Are they arbitrary or do they really mean something in theory? 2. crush_hashmix macro is a part of Jenkins hash function. In the series of crush_hash_rjenkins1_* functions, why input parameters are mixed this way instead of something else? Are they arbitrary or do they really mean something in theory? > For example > crush_hashmix(a, b, hash); > crush_hashmix(c, d, hash); > crush_hashmix(e, x, hash); > crush_hashmix(y, a, hash); > crush_hashmix(b, x, hash); > crush_hashmix(y, c, hash); > crush_hashmix(d, x, hash); > crush_hashmix(y, e, hash); > Do the order and combinations matter something? 3. I read the phrase "funneling hash", but I don't quite understand what does it mean. Thanks. -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
