In a device that has raid 5, and a "raid cache" of 4GB, does this help performance? I have 32MB cache hard drives but I was wanting to know if the 4GB cache will make up for the difference in performance between a 128MB hard drive cache and a 32mb cache for the hard drive. Hardware raid. The front end of the device is a 2008 R2 server, Dell R610.
Will a raid cache be better for performance than hard drive cache speeds
cachehardware-raidraidstorage
Best Answer
With a battery-backed write cache on your RAID controller, you can safely enable write-back mode for your array. Without this, you would need to write-through and suffer the RAID 5 write penalty. HDD cache doesn't really factor in here.
If you have the budget for it, BBWC is a no-brainer on all but the most idle of systems.