[ Thanks to Paul
Shread for this link. ]
“The SAN guys explain that RAID, SAN algorithms, array
controllers and so on either minimize or eliminate fragmentation as
a factor inside the SAN. Some go so far as to say that
defragmentation can even curtail overall performance by interfering
with operations.“The benefits of defragmentation can clearly be seen in DAS
environments,” said Scott DesBles, director of technical solutions
at Compellent Technologies (NYSE: CML). “But in a data center with
virtualized storage such as the Compellent SAN, defragmentation
provides little benefit and can actually hinder the SAN from
managing data as efficiently as it should.”“Such sentiments largely prevail throughout the SAN OEM
community. Yet some analysts and users take a different view.“”Fragmentation is one of those gnarly subjects open for debate
that exists from DAS all the way to SAN attached storage,” said
Greg Schulz, senior analyst and founder of Storage IO Group. “I’m
of the opinion that it is an issue.”