on the network side of things, even though other backups are not oracle related. the sysadmins tell me if they create a 4gb file on the same san (not an oracle datafile) and they backup that 4gb the get a rate of 100mb/s which is double that of an oracle backup. I make the distinction here by saying oracle backup - becasue from my own tests - whether i use rman or not netbackup only goes at 50mb/s for production and a slight improvment on reporting at 60mb/s (likely due to less load). So if a file other than an oracle datafile can go at 100mb/s on the same storage - why do oracle datafiles suffer, rman or no rman? Could it be io generated by the system due to heavy load - but this load is no on reporting and the most i can get out of reporting is an additional 10mb/s (60mb/s) after which the rate begins to dropped - as more channels - or more files are added to the backup. Could the configuraiton of RAID 5 be questioned here - i wonder