On Wed, Apr 30, 2014 at 2:02 PM, Peter Geoghegan <pg@heroku.com> wrote:
>> Of course our current hash indexes have *more* not less contention
>> than btree but I'm pretty comfortable chalking that up to quality of
>> implementation rather than anything intrinsic.
>
> I am not convinced of that.
In commit 76837c1507cb5a5a0048046233568447729e66dd, I remove part
(basically half) of the heavyweight locking used by hash indexes, and
performance improved rather dramatically:
http://www.postgresql.org/message-id/CA+Tgmoaf=nOJxLyzGcbrrY+pe-0VLL0vfHi6tjdM3fFtVwsOmw@mail.gmail.com
I think it's quite reasonable to suppose that getting rid of the
remaining heavyweight locking will help just as much.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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