The Redis CRC-64 implementation is currently 4x slower than it could be. See comparisons at https://github.com/mattsta/crc64-compare
Faster CRC allows COW RDB dumps to take less time, which improves overall memory usage since there will be less memory copying-on-writing on instances with high volumes of writes (especially on RDB dumps of hundreds of GB, which exist in the wild).
tl;dr:
Adler throughput: 1641.694451 MB/s
Redis throughput: 404.099053 MB/s
Adler is 4.06x faster than Redis
Comment From: jcspencer
:+1:
Comment From: madolson
We did end up making crc fast :D