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the format on Tuple(Numeric) and the format to calculate(NumericVar) are different. I understood that to reduce I/O. However, when many comparisons or calculations of NUMERIC are executed, the conversion of Numeric and NumericVar becomes a bottleneck. It is profile result when "create index on NUMERIC column" is executed: % cumulative self self total time seconds seconds calls s/call s/call name 17.61 10.27 10.27 34542006 0.00 0.00 cmp_numerics 11.90 17.21 6.94 34542006 0.00 0.00 comparetup_index 7.42 21.54 4.33 71102587 0.00 0.00 AllocSetAlloc 7.02 25.64 4.09 69084012 0.00 0.00 set_var_from_num 4.87 28.48 2.84 69084012 0.00 0.00 alloc_var 4.79 31.27 2.79 142205745 0.00 0.00 AllocSetFreeIndex 4.55 33.92 2.65 34542004 0.00 0.00 cmp_abs 4.07 36.30 2.38 71101189 0.00 0.00 AllocSetFree 3.83 38.53 2.23 69084012 0.00 0.00 free_var The create index command executes many comparisons of Numeric values. Functions other than comparetup_index spent a lot of cycles for conversion from Numeric to NumericVar. An attached patch enables the comparison of Numeric values without executing conversion to NumericVar. The execution time of that SQL becomes half. o Test SQL (index_test table has 1,000,000 tuples) create index index_test_idx on index_test(num_col); o Test results (executed the test five times) (1)PentiumIII original: 39.789s 36.823s 36.737s 37.752s 37.019s patched : 18.560s 19.103s 18.830s 18.408s 18.853s 4.07 36.30 2.38 71101189 0.00 0.00 AllocSetFree 3.83 38.53 2.23 69084012 0.00 0.00 free_var The create index command executes many comparisons of Numeric values. Functions other than comparetup_index spent a lot of cycles for conversion from Numeric to NumericVar. An attached patch enables the comparison of Numeric values without executing conversion to NumericVar. The execution time of that SQL becomes half. o Test SQL (index_test table has 1,000,000 tuples) create index index_test_idx on index_test(num_col); o Test results (executed the test five times) (1)PentiumIII original: 39.789s 36.823s 36.737s 37.752s 37.019s patched : 18.560s 19.103s 18.830s 18.408s 18.853s (2)Pentium4 original: 16.349s 14.997s 12.979s 13.169s 12.955s patched : 7.005s 6.594s 6.770s 6.740s 6.828s (3)Itanium2 original: 15.392s 15.447s 15.350s 15.370s 15.417s patched : 7.413s 7.330s 7.334s 7.339s 7.339s (4)Ultra Sparc original: 64.435s 59.336s 59.332s 58.455s 59.781s patched : 28.630s 28.666s 28.983s 28.744s 28.595s Atsushi Ogawa |
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| contrib | ||
| doc | ||
| src | ||
| aclocal.m4 | ||
| configure | ||
| configure.in | ||
| COPYRIGHT | ||
| GNUmakefile.in | ||
| Makefile | ||
| README | ||
| README.CVS | ||
PostgreSQL Database Management System ===================================== This directory contains the source code distribution of the PostgreSQL database management system. PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings. The JDBC, ODBC, C++, Python, and Tcl interfaces have been moved to the PostgreSQL Projects Web Site at http://gborg.postgresql.org for separate maintenance. A Perl DBI/DBD driver is available from CPAN. See the file INSTALL for instructions on how to build and install PostgreSQL. That file also lists supported operating systems and hardware platforms and contains information regarding any other software packages that are required to build or run the PostgreSQL system. Changes between all PostgreSQL releases are recorded in the file HISTORY. Copyright and license information can be found in the file COPYRIGHT. A comprehensive documentation set is included in this distribution; it can be read as described in the installation instructions. The latest version of this software may be obtained at ftp://ftp.postgresql.org/pub/. For more information look at our web site located at http://www.postgresql.org/.