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Bruce Momjian 3cf1fd3263 Tom Lane <tgl@sss.pgh.pa.us> writes:
> a_ogawa <a_ogawa@hi-ho.ne.jp> writes:
> > It is a reasonable idea. However, the majority part of MemSet was not
> > able to be avoided by this idea. Because the per-tuple contexts are used
> > at the early stage of executor.
>
> Drat.  Well, what about changing that?  We could introduce additional
> contexts or change the startup behavior so that the ones that are
> frequently reset don't have any data in them unless you are working
> with pass-by-ref values inside the inner loop.

That might be possible. However, I think that we should change only
aset.c about this article.
I thought further: We can check whether context was used from the last
reset even when blocks list is not empty. Please see attached patch.

The effect of the patch that I measured is as follows:

o Execution time that executed the SQL ten times.
(1)Linux(CPU: Pentium III, Compiler option: -O2)
 - original: 24.960s
 - patched : 23.114s

(2)Linux(CPU: Pentium 4, Compiler option: -O2)
 - original: 8.730s
 - patched : 7.962s

(3)Solaris(CPU: Ultra SPARC III, Compiler option: -O2)
 - original: 37.0s
 - patched : 33.7s

Atsushi Ogawa (a_ogawa)
2005-06-04 20:14:12 +00:00
config Clean up printf arg-control test, per Kurt Roeckx. 2005-02-24 01:34:45 +00:00
contrib Prevent to divide by zero and range out of 0..1 2005-06-01 11:45:03 +00:00
doc Add: 2005-06-04 18:12:38 +00:00
src Tom Lane <tgl@sss.pgh.pa.us> writes: 2005-06-04 20:14:12 +00:00
aclocal.m4 Add new auto-detection of thread flags. 2004-04-23 18:15:55 +00:00
configure Rename Rendezvous to Bonjour to match OS/X renaming. 2005-05-15 00:26:19 +00:00
configure.in Rename Rendezvous to Bonjour to match OS/X renaming. 2005-05-15 00:26:19 +00:00
COPYRIGHT Tag appropriate files for rc3 2004-12-31 22:04:05 +00:00
GNUmakefile.in Remove the contents of the src/corba subdirectory: this has been dead code 2005-05-01 06:15:51 +00:00
Makefile please find attached an alternate submission which addresses open item 2004-10-06 08:50:02 +00:00
README Remove more traces of libpgtcl from the source tree. Also, make some 2004-10-01 02:00:44 +00:00
README.CVS Some further editorializing on README.CVS. 2004-03-28 06:09:08 +00:00

PostgreSQL Database Management System
=====================================
  
This directory contains the source code distribution of the PostgreSQL
database management system.

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