The default stripe breadth on a metadata storage pool is 256 blocks. However, this is way, way too high. Quantum recommends using a 16 or 64 block stripe breadth for metadata storage pools. If you have a relatively small volume with a small number of files then use 16 and if you have a larger environment with big files use 64. As with many things re: Xsan the tuning per environment is where you will get the biggest bang for your buck, but it is worth noting that no matter which way you go, this is a setting that should be changed on each deployment in order to keep with Quantum best practices.