Re: ECPG patch to use prepare for improved performance

This has been saved for the 8.4 release:

http://momjian.postgresql.org/cgi-bin/pgpatches_hold

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

William Lawrance wrote:
>
> This updated patch for ECPG uses the current routines by
> default. If an environment variable (ECPGUSEPREPARE) is set
> to "yes", it uses the new routine that prepares and
> caches each statement.
>
>
>
>
> -----Original Message-----
> From: Michael Meskes [mailto:meskes(at)postgresql(dot)org]
> Sent: Thursday, May 10, 2007 3:01 AM
> To: William Lawrance
> Cc: Michael Meskes; Pgsql-Patches
> Subject: Re: [PATCHES] ECPG patch to use prepare for improved
> performance
>
>
> On Wed, May 09, 2007 at 01:12:17PM -0700, William Lawrance wrote:
> > 2. The performance was improved by about 1 hour in the 3 hour
> > elapsed time of the application. This is important to the
> > customer in terms of accomplishing his work load in the
> > time that has been allotted, based on his experience with DB2.
> > Without this improvement, he is likely to consider it too slow.
>
> But this only holds for one customer. I don't think this will hold for
> every single application. At least I do not see a reason why this
> should hold everytime.
>
> > I would like to emphasize that we aren't measuring an artificial
> > test program; this is a real customer's application. We loaded
> > 7 million rows into 217 tables to run the application. I believe
> > it is representative of many real batch applications.
>
> But how about non-batch applications?
>
> > Is there reason not to prepare each statement?
>
> I'm completely against forcing such a design decision on the programmer.
> Hopefully I will be able to add a real prepare statement soon.
>
> > Could it be predicated upon a user supplied option ?
>
> Yes, this is fine with me. If you could rearrange the patch I will test
> and commit it.
>
> Michael
> --
> Michael Meskes
> Email: Michael at Fam-Meskes dot De, Michael at Meskes dot (De|Com|Net|Org)
> ICQ: 179140304, AIM/Yahoo: michaelmeskes, Jabber: meskes(at)jabber(dot)org
> Go SF 49ers! Go Rhein Fire! Use Debian GNU/Linux! Use PostgreSQL!
[ Attachment, skipping... ]

>
> ---------------------------(end of broadcast)---------------------------
> TIP 5: don't forget to increase your free space map settings

--
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. +