Per, we are keeping an eye on Posix AIO in Linux as the well as the DIRECT IO flush option of files. The file os0file.c contains some rudiments for the Posix AIO use in InnoDB.
Monty had some bitter experiences from Solaris AIO years ago. We have been waiting for the Linux support of Posix AIO to age a bit. In Windows NT/2000/XP unbuffered AIO seems to work ok, and provides better performance than ordinary file IO. Best regards, Heikki Tuuri Innobase Oy --- InnoDB - transactions, hot backup, and foreign key support for MySQL See http://www.innodb.com, download MySQL-Max from http://www.mysql.com sql query .................. Subject: POSIX Asynchronous I/O in InnoDB? From: Per Andreas Buer Date: 14 Jan 2003 11:47:55 +0100 ---------------------------------------------------------------------------- ---- Hi. I see InnoDB uses Asynchronous IO on Windows NT but not on Linux. There are patches, made by SGI, which enables asynchronous IO on Linux 2.4 (http://oss.sgi.com/projects/kaio/). Are there any plans to support native asynchronous IO in InnoDB? Quoted from the project site: Preliminary experience with KAIO have shown over 35% improvement in database performance tests. Unit tests (which only perform I/O) using KAIO and Raw I/O have been successful in achieving 93% saturation with 12 disks hung off 2 X 40 MB/s Ultra-Wide SCSI channels. We believe that these encouraging results are a direct result of implementing a significant part of KAIO in the kernel using split-phase I/O while avoiding or minimizing the use of any globally contented locks. -- Per Andreas Buer sql,query,queries,smallint --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
