On 2011-10-31, at 4:22 AM, Theodore Tso <tytso@xxxxxxx> wrote: > For cluster file systems, such as when you might build Hadoop on top of ext4, there's no real advantage of using RAID arrays as opposed to having single file systems on each disk. In fact, due to the specd of being able to check multiple disk spindles in parallel, it's advantageous to build cluster file systems on single disk file systems. For Lustre at least there are a number of reasons why it uses large RAID devices to store the data instead of many small devices: - fewer devices that need to be managed. Lustre runs on systems with more than 13000 drives, and having to manage connection state for that many internal devices is a lot of overhead. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html