CityHash128 isn't thorough enough
GoogleCodeExporter opened this issue · 2 comments
GoogleCodeExporter commented
What steps will reproduce the problem?
1. CityHash128() all 144-byte strings with 3 bits set
2. check for collisions
What is the expected output? What do you see instead?
0 collisions are expected. 87 collisions are actually seen. I saw the first
collision after about 8 million of the keys. That's the expected collision
rate for a 46-bit hash, not a 128-bit hash.
(I had a hash of my own last year, AkronHash, that was also a 128-bit hash
evolved from MurmurHash. I quickly withdrew it due to similar quality issues.
My current attempt, SpookyHash, passes this test.)
Original issue reported on code.google.com by bobjenki...@gmail.com
on 28 Jul 2011 at 8:00
GoogleCodeExporter commented
Thanks Bob!
We will fix this in a future release.
Original comment by gp...@google.com
on 31 Aug 2011 at 8:43
- Changed state: Started
- Added labels: Priority-High
- Removed labels: Priority-Medium
GoogleCodeExporter commented
Fixed in version 1.0.3. Thanks again for the bug report!
Original comment by gp...@google.com
on 6 Oct 2011 at 9:05
- Changed state: Fixed