Striped arrays
are more suited to large I/Os or
to multiple smaller, random I/Os.
0+1 Striping and mirroring
Twice the cost of
unprotected storage.
Best of both worlds??”
striping increases read
and write performance
and mirroring for
redundancy avoids
???read-modify-write???
overhead of RAID-5.
Same usage as RAID-0, but
provides protection from disk
failure.
5 Striping with rotating
or distributed
parity
Storage capacity is
reduced by 1/N,
where N is the number
of disks in the
array. For example,
the storage is
reduced by 20%, or
1/5 of the total disk
storage, for a 5-disk
array.
Parity data is spread
across all disks, avoiding
the potential bottleneck
found in some other
types of RAID arrays.
Striping increases read
performance. Maintaining
parity data adds
additional I/O, decreasing
write performance.
For each write, the associated
parity data must
be read, modified, and
written back to disk. This
is referred to as the
???read-modify-write???
penalty.
Cost-effective solution for all Oracle
data except redo logs.
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