RMAN Performance Hiccups Resolved

This is in relation with the earlier post "Investigating Hiccups in RMAN Implementation for Production Database", where I was trying to find out the severe performance issues when I carried out RMAN Backup on a network storage (SAN, available to me as NAS). Here are the findings from the earlier tests:

The backup tablespace size is 1.36 GB with one datafile.
The backup piece size in all 3 test cases is 1.1 GB each.
RMAN Backup Time at 3 location:

• Local Backup Duration (D:\oracle\backup): 04:55 minutes
• Shared Backup Duration (\\testdb\orcl): 02:25 minutes
• Shared SAN Duration (\\blade5\mis\backup\RMAN): 26:25 minutes

So, basically I was expecting a lot more better performance or atleast similar performance to the shared backup location for RMAN Backups. We (me, IT Guys and Oracle Support Guys) really were not able to figure out why it was happening.

With the crash that occured on the 11th May, we had the server completely recovered and rebuilt. In the event of rebuilding the server, the IT Administrators upgraded the O/S from Windows 2000 Server Standard Edition to Windows 2003 Server Standard Edition.

After cloning the Recovered Database, I setup RMAN Backup Jobs and did a trial backup on the Shared SAN location, and guess what!!!! My backup which used to take 8 hrs to 13 hrs to complete on the Shared SAN location, now finished in 35-40 minutes.

I guess there was something related to the O/S after all. What change resolved the backup performance issue, is still unknown, except for the fact that upgrading to Windows 2003 Server helped resolve the backup performance issue.