On Wed, 21 Mar 2012, maillist reader wrote:
I read though that ZFS does not have a "defragmentation" tool, is this still
the case? It would seem with such a
performance difference between "sequential reads" and "random reads" for
raidzN's, a defragmentation tool would be
very high on ZFS's TODO list ;).
Zfs does not usually suffer significantly from fragmentation. To be
clear, "random reads" means random file access and necessary head
seeks. Any mechanical-based device will suffer from this and it is
not specific to zfs.
Something which is specific to zfs is that within a zdev, a stripe
must be read and written completely. Partial stripe reads are not
supported since a full read is necessary in order to validate the
GraphicsMagick Maintainer, http://www.GraphicsMagick.org/
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