Re: [HACKERS] [POC] hash partitioning - Mailing list pgsql-hackers

From Robert Haas
Subject Re: [HACKERS] [POC] hash partitioning
Date
Msg-id CA+Tgmob3-kMhdt2Xrp4dnvMByWTZMX5Q=hxiNSaGGPm8sidmYQ@mail.gmail.com
Whole thread Raw
In response to Re: [HACKERS] [POC] hash partitioning  (amul sul <sulamul@gmail.com>)
Responses Re: [HACKERS] [POC] hash partitioning
List pgsql-hackers
On Thu, Oct 12, 2017 at 9:08 AM, amul sul <sulamul@gmail.com> wrote:
> How about combining high 32 bits and the low 32 bits separately as shown below?
>
> static inline uint64
> hash_combine64(uint64 a, uint64 b)
> {
>     return (((uint64) hash_combine((uint32) a >> 32, (uint32) b >> 32) << 32)
>             | hash_combine((unit32) a, (unit32) b));
> }

I doubt that's the best approach, but I don't have something specific
to recommend.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company


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