Hi, Here, I got two confusing questions about Linux MD: I. Why when initial create RAID5, mdadm marks a physical disk as "spare"? Is this for random write with RMW, or for "sync" speed? II. The write intent bitmap, each disk in RAID with a "write intent bitmap", or the whole RAID with one "write intent bitmap"? If the whole RAID with one "write intent bitmap", how to know which disk's data need reconstruct, or just use the data disks' data to calculate the P data, and write to the P disk? If the only one "write intent bitmap", how to decide which disk to save the "write intent bitmap"? And is there has any MD design architecture document? Thanks a lot -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html