Archive for February, 2009

Space Management and Data ONTAP– Part 5

Eventually, as more files are changed, more and more blocks will be assigned from the snapshot reserve.  The df –k command will show the amount of space being used within the active file system and in the .snapshot directory. There is nothing magical about the 20% number.  Sometimes we may want to decrease the percentage […]

Space Management and Data ONTAP– Part 4

We’ve been discussing how the WAFL file system allocates space for volumes, including the   meaning of space guarantees, space reservations and fractional reserve.  Now I’d like to look a little deeper at snapshots and space management from a snapshot perspective. Basically, when a snapshot occurs all the blocks associated with data in the volume are […]