Dell Raid 0+1

I am recommending that we change our Raid Configuration on some of our
Servers from Raid 5 to Raid 0+1; we are experiencing severe IO
bottlenecks.

Our hardware guys are pushing back a bit. They claim that Dell has a
weird implementation of 0+1 and told me something about one drive
filling up before it begins to write to the next. They claimed that
this gets rid of most of the benefits of 0+1.


I know that 0+1 is not as good as 10 for availability, fault tolerance,

and rebuilding, but shouldn't the write throughput be about the same?


Setup:
Poweredge 2850
Powervault 220S
Perc 4/DC Controller 1
Perc 4e/DI Controller 0