This section describes some restrictions of HADB with certain file systems.
HADB supports the ext2 and ext3 file systems on Red Hat Enterprise Linux 3.0. For Red Hat Enterprise Linux 2.1, HADB supports the ext2 file system.
When using the Veritas File System on Solaris, HADB writes the message WRN: Direct disk I/O mapping failed to the history files. This message indicates that HADB cannot turn on direct input/output (I/O) for the data and log devices. Direct I/O reduces the CPU cost of writing disk pages. It also reduces overhead of administering “dirty” data pages in the operating system.
To use direct I/O with Veritas File System, do one of the following:
Create the data and log devices on a file system that is mounted with the option mincache=direct. This option applies to all files created on the file system. Check the mount_vxfs(1M) command for details.
Use the Veritas Quick I/O facility to perform raw I/O to file system files. For details, see the VERITAS File System 4.0 Administrator’s Guide for Solaris.
These configurations have not been tested with the Sun Java System Application Server.