Message on logs: AIO wasn't located on this platform
Possible causes are:
Linux is not your platform
Just ignore the message as NIO will be selected automatically or change the journal type to NIO on jbm-configuration.xml
The JBoss Messaging JNI wrapper is not on library.path
Solution: Make sure you have libJBMLibAIO32.so or libJBMLibAIO64.so as provided on the download package.
libaio is not installed
Make sure you have libaio installed at your Linux distribution. This could be done as yum install libaio1 on Fedora or apt-get install libaio1 on Debian. (Refer to your manual to how to upgrade or install packages)
libaio is very old
We have been using and testing libaio 0.3.106 and Kernel 2.6. If you have older versions you might need to upgrade or change the journal type to NIO on jbm-configuration.xml
Low response time even though the CPU and IO seems ok
Possible causes are:
You are using short transactions in your system and you don't have TCPNoDelay set
Make sure you have remoting-tcp-nodelay set to true on jbm-configuration.xml
The journal directory is a NFS
You shouldn't use the journal over a NFS. Make sure you have direct access to the disk device.
You are using Asynchronous IO on Linux and you don't have an ext3 or ext2 file system
If using AIO, make sure the journal folder is on an ext2 or ext3 file system.