Oracle Database Discussions

RDBMS versions: 10.2.0.5, 11.2.0.3
Current Platform : AIX 6

For cost savings , we were planning to move half of our DB servers from AIX to Oracle Enterprise Linux 6 (UEK) and rest to Solaris 11. Already negotiating with Oracle on the Pricing .

One of our managers (a big fan of IBM ) is complaining that Linux is bad at asynchronous I/O. He asked us to just google Linux and AIO. Things like the following came up.

http://bouliiii.blogspot.com/2011/10/disk-asynchronous-io-mess-on-linux-and.html

Basically , this is what I gather about Asynchronous I/O. A process can issue multiple Write requests to Linux/Unix kernel and continue doing other stuff and in the mean time the kernel will perform all your I/O requests in the Disks and inform you that the all your requests have been done. It is parallel processing with respect to I/O. Am I right ?

I wonder what Mr. StallMan and Mr. Torvalds think about these allegations ?

BTW. Any idea what is the significance of term 'Sub' in I/O Subsystems ? What is so 'Sub' about it ?