Re: UTF8MatchText

From: Bruce Momjian <bruce(at)momjian(dot)us>
To: ITAGAKI Takahiro <itagaki(dot)takahiro(at)oss(dot)ntt(dot)co(dot)jp>
Cc: Andrew - Supernews <andrew(at)supernews(dot)net>, pgsql-patches(at)postgresql(dot)org
Subject: Re: UTF8MatchText
Date: 2007-04-09 20:16:10
Message-ID: 200704092016.l39KGAi00878@momjian.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers pgsql-patches


Patch removed, updated version submitted.

---------------------------------------------------------------------------

ITAGAKI Takahiro wrote:
> "Andrew - Supernews" <andrew(at)supernews(dot)net> wrote:
>
> > ITAGAKI> I think all "safe ASCII-supersets" encodings are comparable
> > ITAGAKI> by bytes, not only UTF-8.
> >
> > This is false, particularly for EUC.
>
> Umm, I see. I updated the optimization to be used only for UTF8 case.
> I also added some inlining hints that are useful on my machine (Pentium 4).
>
>
> x1000 of LIKE '%foo% on 10000 rows tables [ms]
> encoding | HEAD | P1 | P2 | P3
> -----------+-------+-------+-------+-------
> SQL_ASCII | 7094 | 7120 | 7063 | 7031
> LATIN1 | 7083 | 7130 | 7057 | 7031
> UTF8 | 17974 | 10859 | 10839 | 9682
> EUC_JP | 17032 | 17557 | 17599 | 15240
>
> - P1: UTF8MatchText()
> - P2: P1 + __inline__ GenericMatchText()
> - P3: P2 + __inline__ wchareq()
> (The attached patch is P3.)
>
> Regards,
> ---
> ITAGAKI Takahiro
> NTT Open Source Software Center
>

[ Attachment, skipping... ]

>
> ---------------------------(end of broadcast)---------------------------
> TIP 7: You can help support the PostgreSQL project by donating at
>
> http://www.postgresql.org/about/donate

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://www.enterprisedb.com

+ If your life is a hard drive, Christ can be your backup. +

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Jim Nasby 2007-04-09 20:39:24 Re: Effects of GUC settings on automatic replans
Previous Message Andrew Dunstan 2007-04-09 20:07:16 Re: [HACKERS] Arrays of Complex Types

Browse pgsql-patches by date

  From Date Subject
Next Message Martijn van Oosterhout 2007-04-09 21:12:24 Re: [HACKERS] Arrays of Complex Types
Previous Message Andrew Dunstan 2007-04-09 20:07:16 Re: [HACKERS] Arrays of Complex Types