Crucial Paradigm Australia Official Blog
3ware
If you have ever had 3ware cards underperforming before you have probably found out about the storsave profile and how it can effect performance of your RAID array.
Changing your storsave profile can easily be done on the fly without rebooting your server by using the tw_cli utility.
tw_cli /c0/u0 set storsave=balance
Where c0 is the RAID card, and u0 is the array you wish to change the profile for. There are 3 profiles, protect which is the slowest and most secure. Balanced which you should be using if you have a BBU on the RAID card, and then finally performance which doesn’t even use the BBU even if you have one! We set our arrays to balanced when we use a BBU
You can add a hotspare drive to a 3ware controller using the tw_cli utility. Example:
tw_cli /c0 add type=spare disk=14
Where c0 is the controller, and 14 is the port. You can show which ports are being used in which arrays by running:
tw_cli /c0 show
3Ware cards do not always make it easy to export drives as JBOD, or for single drives. To get this working it needs to be done through the 3Ware CLI (tw_cli on Linux):
tw_cli maint createunit c0 rsingle p0
Where c0 is the first RAID card in the server, and p0 is the first drive on the controller. You need to run this command for each drive you wish to set to JBOD.