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Find the performance impact of your system's Autoloader connection in
Table 31
Table 31 Performance impact of various Autoloader connections
Recommendations
Performance impact
Connection type
Ultra 320 is an excellent transport
medium, but only has enough bandwidth
for one LTO-3 or LTO-4 drive per bus.
NOTE:
If the parallel SCSI cables are not
designed for Ultra 320 speeds or
more than a couple devices are on
the parallel SCSI bus, the bus may
slow down to Ultra 160 speed.
GOOD
. When fully used, an Ultra 320
SCSI connection can provide enough
bandwidth for the following number of
tape drives, assuming 2:1 compression:
•
LTO-2: 2
•
LTO-3, LTO-4: 1
Parallel SCSI: Ultra 320
Ultra 160 is a good transport medium,
but does not have enough bandwidth
for LTO-3 or LTO-4 tape drives. If using
LTO-3 or LTO-4, upgrade to an Ultra
320 HBA, especially if you have greater
than 2:1 compressible data.
•
LTO-2:
GOOD
. When fully used and
assuming that the connection to the
disks does not force the speed to a
lower parallel SCSI type, an Ultra
160 connection can provide enough
bandwidth for two LTO-2 tape drives.
•
LTO-3:
MARGINAL
. An Ultra 160
connection is barely adequate for an
LTO-3 tape drive. The bus would be
saturated with 2:1 compressible
data.
•
LTO-4:
POOR
. An LTO-4 tape drive
is unable to sustain maximum transfer
speeds with 2:1 compressible data.
Parallel SCSI: Ultra 160
Upgrade to Ultra 320.
•
LTO-2:
MARGINAL
. Ultra 2 (80)
barely has enough bandwidth for
one LTO-2 drive.
•
LTO-3, LTO-4:
POOR
. An Ultra 2 (80)
connection is inadequate for an LTO-
3 or LTO-4 tape drive.
Parallel SCSI: Ultra 2
(80)
Upgrade to Ultra 320.
Ultra Wide and Fast Wide are
inadequate for all of the currently
supported tape drives.
Parallel SCSI: Ultra
Wide, Fast Wide
POOR
. One gigabit fibre is inadequate
for an LTO tape drive.
Fibre Channel: 1 Gb
•
LTO-5:
POOR
. Two gigabit fibre is
inadequate for an LTO-5 tape drive.
Fibre Channel: 2 Gb
GOOD
. When fully used, 4 Gb and 8
Gb Fibre Channel have sufficient
bandwidth for all supported tape drives.
Fibre Channel: 4 Gb, 8
Gb
GOOD
. When fully used, 3 Gb and 6
Gb SAS have sufficient bandwidth for
all supported tape drives.
SAS: 3 Gb, 6 Gb
Troubleshooting
126
Summary of Contents for StorageWorks 1/8
Page 14: ...14 ...
Page 26: ...Features and overview 26 ...
Page 106: ...Operating the Tape Autoloader 106 ...
Page 156: ...Troubleshooting 156 ...
Page 168: ...Upgrading and servicing the Tape Autoloader 168 ...
Page 172: ...Support and other resources 172 ...
Page 174: ...Technical specifications 174 ...
Page 179: ...HP StorageWorks 1 8 G2 Tape Autoloader User and service guide 179 ...
Page 188: ...Battery replacement notices Dutch battery notice Regulatory compliance and safety 188 ...
Page 190: ...Italian battery notice Japanese battery notice Regulatory compliance and safety 190 ...
Page 192: ...Regulatory compliance and safety 192 ...
Page 194: ...Electrostatic discharge 194 ...
Page 204: ...204 ...