53f1ca59b5
We need not wait until the commit record is durably on disk, because in the event of a crash the page we're updating with hint bits will be gone anyway. Per off-list report from Heikki Linnakangas, this can significantly degrade the performance of unlogged tables; I was able to show a 2x speedup from this patch on a pgbench run with scale factor 15. In practice, this will mostly help small, heavily updated tables, because on larger tables you're unlikely to run into the same row again before the commit record makes it out to disk.
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. PostgreSQL has many language interfaces, many of which are listed here: http://www.postgresql.org/download 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 http://www.postgresql.org/download/. For more information look at our web site located at http://www.postgresql.org/.