&KDSWHU.'LDJQRVLV3URJUDP*'7021
Drives, the performance of the Logical Drives forming a RAID Host Drive are shown in the
menu
Logical Drives
. The performance data displayed here gives immediate information on
the quality of a given Host Drive. When judging the indicated performance of Logical Drives
belonging to a RAID Host Drive, the following considerations should be taken into account:
(a) RAID 0, RAID 1, RAID 10 and RAID 5 Host Drives
If a certain Logical Drive shows poor performance for a longer period (when compared to
the other Logical Drives), this Logical Drive impairs the overall performance, making it the
bottle neck
of the entire RAID Host Drive.
(b) RAID 4 Host Drives
In principle, the same as in (a) applies to RAID 4 Host Drives, with the exception made for
the parity Logical Drive. The poor performance can have various reasons: the SCSI drive
forming the Logical Drive
is too slow (different from the other SCSI drives with regard to type or manufacturer)
has wrong parameters (SCSI II, disk cache, tagged queues etc.)
has too many defects, causing the read/write actuator to have to move to
alternate tracks
very often
When setting up RAID 4/5 Host Drives, please observe the notes on RAID 4/5 Host Drives
exposed in the chapter
GDTSETUP in Detail
.