| From: | Andrew Gierth <andrew(at)tao11(dot)riddles(dot)org(dot)uk> |
|---|---|
| To: | Peter Geoghegan <pg(at)heroku(dot)com> |
| Cc: | Pg Hackers <pgsql-hackers(at)postgresql(dot)org>, Robert Haas <robertmhaas(at)gmail(dot)com> |
| Subject: | Re: Re: Abbreviated keys for Numeric |
| Date: | 2015-01-26 23:12:05 |
| Message-ID: | 87ppa1f8me.fsf@news-spur.riddles.org.uk |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
>>>>> "Peter" == Peter Geoghegan <pg(at)heroku(dot)com> writes:
Peter> What I find particularly interesting about this patch is that it
Peter> makes sorting numerics significantly faster than even sorting
Peter> float8 values,
I get a much smaller difference there than you do.
Obvious overheads in float8 comparison include having to check for NaN,
and the fact that DatumGetFloat8 on 64bit doesn't get inlined and forces
a store/load to memory rather than just using a register. Looking at
those might be more beneficial than messing with abbreviations.
--
Andrew (irc:RhodiumToad)
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Peter Geoghegan | 2015-01-26 23:35:44 | Re: Re: Abbreviated keys for Numeric |
| Previous Message | David Steele | 2015-01-26 23:08:48 | Re: pg_upgrade and rsync |