Ceph

ISA-L, a component in Ceph (https://github.com/ceph/isa-l/tree/bee5180a1517f8b5e70b02fcd66790c623536c5d) provides multiple CRC32 implementations. To date, Ceph has only used the lowest common denominator of these implementations (crc32_iscsi_00), which runs on all CPUs which provide the CRC32C instruction.

There is an alternative implementation which leverages SSE4.1 (PCLMULQDQ - carryless vectorized multiplication) to provide a much more efficient, faster implementation for CPUs which provide the SSE4.1 instruction set. A whitepaper for this implemenation of CRC32 can be found here: https://fossies.org/linux/zlib-ng/doc/crc-pclmulqdq.pdf

This instruction came to be in 2008 (Westmere), and as such is now quite ubiquitous -- meaning that if we add support for this CRC32 implementation, the vast majority of Ceph users stand to benefit to some degree.