DB Direct I/O setting

This is only good for Unix databases. It will adversely affect performance in Windows.

Justin Muller
Velocity Development Group, LLC

From: vantage@yahoogroups.com [mailto:vantage@yahoogroups.com] On Behalf Of zacwoodward
Sent: Tuesday, June 14, 2011 6:07 PM
To: vantage@yahoogroups.com
Subject: [Vantage] DB Direct I/O setting



There is an option for Direct I/O that is disabled by default in OpenEdge. The description of it makes it sound like is something that would be good to enable. Does anyone have any experience with this setting?

The description of Direct I/O is below

"Enables the Direct I/O property, which opens all files in unbuffered mode. Direct I/O enables the database to use an I/O technique that bypasses the operating system buffer pool and transfers data directly from a buffer to disk.

This technique has some advantages over buffered reads and writes, such as avoiding the overhead of maintaining the operating system buffer pool, and eliminating competition for operating system buffers between the database and other programs. The operating system buffer-pool algorithms are designed for efficient sequential file access; the OpenEdge buffer-pool algorithms are more efficient for access to an OpenEdge RDBMS.
The Direct I/O check box is cleared by default."

"Zac" Jason Woodward
Network Administrator
Intermountain Electronics, Inc.
O: 877-544-2291
M: 435-820-6515
F: 435-637-9601
www.ie-corp.com<http://www.ie-corp.com>



[Non-text portions of this message have been removed]
There is an option for Direct I/O that is disabled by default in OpenEdge. The description of it makes it sound like is something that would be good to enable. Does anyone have any experience with this setting?

The description of Direct I/O is below

"Enables the Direct I/O property, which opens all files in unbuffered mode. Direct I/O enables the database to use an I/O technique that bypasses the operating system buffer pool and transfers data directly from a buffer to disk.

This technique has some advantages over buffered reads and writes, such as avoiding the overhead of maintaining the operating system buffer pool, and eliminating competition for operating system buffers between the database and other programs. The operating system buffer-pool algorithms are designed for efficient sequential file access; the OpenEdge buffer-pool algorithms are more efficient for access to an OpenEdge RDBMS.
The Direct I/O check box is cleared by default."

"Zac" Jason Woodward
Network Administrator
Intermountain Electronics, Inc.
O: 877-544-2291
M: 435-820-6515
F: 435-637-9601
www.ie-corp.com