On 5/23/23 6:06 PM, Eric Biggers wrote:
On Tue, May 23, 2023 at 05:45:02PM -0400, J. corwin Coburn wrote:
MurmurHash3 is a fast, non-cryptographic, 128-bit hash. It was originally
written by Austin Appleby and placed in the public domain. This version has
been modified to produce the same result on both big endian and little
endian processors, making it suitable for use in portable persistent data.
Signed-off-by: J. corwin Coburn <corwin@xxxxxxxxxx>
---
drivers/md/dm-vdo/murmurhash3.c | 175 ++++++++++++++++++++++++++++++++
drivers/md/dm-vdo/murmurhash3.h | 15 +++
2 files changed, 190 insertions(+)
create mode 100644 drivers/md/dm-vdo/murmurhash3.c
create mode 100644 drivers/md/dm-vdo/murmurhash3.h
Do we really need yet another hash algorithm?
xxHash is another very fast non-cryptographic hash algorithm that is already
available in the kernel (lib/xxhash.c).
- Eric
The main reason why vdo uses Murmur3 and not xxHash is that vdo has been
in deployment since 2013, and, if I am reading correctly, xxHash did not
have a 128 bit variant until 2019.
It would certainly be possible to switch vdo to xxHash, but it would be
problematic for existing users.
corwin
