On 2020-04-16 12:18, Medvedkin, Vladimir wrote: > Hi Mattias, > > -----Original Message----- > From: Mattias Rönnblom <mattias.ronnb...@ericsson.com> > Sent: Wednesday, April 15, 2020 7:52 PM > To: Medvedkin, Vladimir <vladimir.medved...@intel.com>; dev@dpdk.org > Cc: Ananyev, Konstantin <konstantin.anan...@intel.com>; Wang, Yipeng1 > <yipeng1.w...@intel.com>; Gobriel, Sameh <sameh.gobr...@intel.com>; > Richardson, Bruce <bruce.richard...@intel.com> > Subject: Re: [dpdk-dev] [PATCH v3 0/4] add new k32v64 hash table > > On 2020-04-15 20:17, Vladimir Medvedkin wrote: >> Currently DPDK has a special implementation of a hash table for >> 4 byte keys which is called FBK hash. Unfortunately its main drawback >> is that it only supports 2 byte values. >> The new implementation called K32V64 hash supports 4 byte keys and 8 >> byte associated values, which is enough to store a pointer. >> >> It would also be nice to get feedback on whether to leave the old FBK >> and new k32v64 implementations or deprecate the old one? > > Do you think it would be feasible to support custom-sized values and remain > efficient, in a similar manner to how rte_ring_elem.h does things? > > I'm afraid it is not feasible. For the performance reason keys and > corresponding values resides in single cache line so there are no extra > memory for bigger values, such as 16B.
Well, if you have a smaller value type (or key type) you would fit into something less-than-a-cache line, and thus reduce your memory working set further. >> v3: >> - added bulk lookup >> - avx512 key comparizon is removed from .h >> >> v2: >> - renamed from rte_dwk to rte_k32v64 as was suggested >> - reworked lookup function, added inlined subroutines >> - added avx512 key comparizon routine >> - added documentation >> - added statistic counters for total entries and extended entries(linked >> list) >> >> Vladimir Medvedkin (4): >> hash: add k32v64 hash library >> hash: add documentation for k32v64 hash library >> test: add k32v64 hash autotests >> test: add k32v64 perf tests >> >> app/test/Makefile | 1 + >> app/test/autotest_data.py | 12 ++ >> app/test/meson.build | 3 + >> app/test/test_hash_perf.c | 130 ++++++++++++ >> app/test/test_k32v64_hash.c | 229 ++++++++++++++++++++++ >> doc/api/doxy-api-index.md | 1 + >> doc/guides/prog_guide/index.rst | 1 + >> doc/guides/prog_guide/k32v64_hash_lib.rst | 66 +++++++ >> lib/Makefile | 2 +- >> lib/librte_hash/Makefile | 13 +- >> lib/librte_hash/k32v64_hash_avx512vl.c | 56 ++++++ >> lib/librte_hash/meson.build | 17 +- >> lib/librte_hash/rte_hash_version.map | 6 +- >> lib/librte_hash/rte_k32v64_hash.c | 315 >> ++++++++++++++++++++++++++++++ >> lib/librte_hash/rte_k32v64_hash.h | 211 ++++++++++++++++++++ >> 15 files changed, 1058 insertions(+), 5 deletions(-) >> create mode 100644 app/test/test_k32v64_hash.c >> create mode 100644 doc/guides/prog_guide/k32v64_hash_lib.rst >> create mode 100644 lib/librte_hash/k32v64_hash_avx512vl.c >> create mode 100644 lib/librte_hash/rte_k32v64_hash.c >> create mode 100644 lib/librte_hash/rte_k32v64_hash.h >>
