[PATCH v2 0/4] hash: add SVE support for bulk key lookup

Yoan Picchi yoan.picchi at arm.com
Fri Oct 20 18:51:55 CEST 2023


This patchset adds SVE support for the signature comparison in the cuckoo
hash lookup and improves the existing NEON implementation. These
optimizations required changes to the data format and signature of the
relevant functions to support dense hitmasks (no padding) and having the
primary and secondary hitmasks interleaved instead of being in their own
array each.

Benchmarking the cuckoo hash perf test, I observed this effect on speed:
  There are no significant changes on Intel (ran on Sapphire Rapids)
  Neon is up to 7-10% faster (ran on ampere altra)
  128b SVE is about 3-5% slower than the optimized neon (ran on a graviton
    3 cloud instance)
  256b SVE is about 0-3% slower than the optimized neon (ran on a graviton
    3 cloud instance)

Yoan Picchi (4):
  hash: pack the hitmask for hash in bulk lookup
  hash: optimize compare signature for NEON
  test/hash: check bulk lookup of keys after collision
  hash: add SVE support for bulk key lookup

 .mailmap                   |   2 +
 app/test/test_hash.c       |  99 ++++++++++----
 lib/hash/rte_cuckoo_hash.c | 264 +++++++++++++++++++++++++++++--------
 lib/hash/rte_cuckoo_hash.h |   1 +
 4 files changed, 287 insertions(+), 79 deletions(-)

-- 
2.25.1



More information about the dev mailing list