Striping at a Higher Level
When a RAID system writes a file using a RAID 0 (striping) scheme, it breaks the file
into segments and spreads them across disk drives in the RAID array. This improves
performance by writing parts of the file in parallel (instead of one part at a time) to
disks in the array. Xsan applies this same technique in the storage hierarchy. Within
each storage pool in a volume, Xsan stripes file data across the individual LUNs that
make up the storage pool. Performance is improved because data is written in parallel.
You can tune SAN performance to suit a critical application by adjusting the amount of
data written to each LUN in a storage pool (the “stripe breadth”).