On Mon, 16 Mar 2020 18:27:40 +0000 "Medvedkin, Vladimir" <vladimir.medved...@intel.com> wrote:
> Hi Morten, > > > On 16/03/2020 14:39, Morten Brørup wrote: > >> From: dev [mailto:dev-boun...@dpdk.org] On Behalf Of Vladimir Medvedkin > >> Sent: Monday, March 16, 2020 2:38 PM > >> > >> 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 DWK (double word key) hash > >> supports 8 byte 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 DWK implementations, or whether to deprecate the old one? > > <rant on> > > > > Who comes up with these names?!? > > > > FBK (Four Byte Key) and DWK (Double Word Key) is supposed to mean the same. > > Could you use 32 somewhere in the name instead, like in int32_t, instead of > > using a growing list of creative synonyms for the same thing? Pretty > > please, with a cherry on top! > > > That's true, at first I named it as fbk2, but then it was decided to > rename it "dwk", so that there was no confusion with the existing FBK > library. Naming suggestions are welcome! > > > > > And if the value size is fixed too, perhaps the name should also indicate > > the value size. > > > > <rant off> > > > > It's a shame we don't have C++ class templates available in DPDK... > > > > In other news, Mellanox has sent an RFC for an "indexed memory pool" > > library [1] to conserve memory by using uintXX_t instead of pointers, so > > perhaps a variant of a 32 bit key hash library with 32 bit values (in > > addition to 16 bit values in FBK and 64 bit in DWK) would be nice > > combination with that library. > > > > [1]: http://mails.dpdk.org/archives/dev/2019-October/147513.html > > > > > > Med venlig hilsen / kind regards > > - Morten Brørup > > Why is this different (or better) than existing rte_hash. Having more flavors is not necessarily a good thing (except in Gelato)
