HP MPX200 Multifunction Router User Manual
Page 108
NOTE:
The MPX200 uses the Maximum Concurrent I/Os parameter to generate migration
I/Os for the jobs configured on the array. Because the array may also be used by the hosts,
migration I/Os from the MPX200 and host I/Os may result in I/Os that exceed the maximum
concurrent I/Os supported by array.
Arrays are equipped to handle this scenario and start returning the SCSI status as 0x28(TASK
SET FULL)
or0x08(BUSY) for the incoming I/Os that exceed the arrays’ maximum concurrent
I/O limit. The TASK SET FULL or BUSY SCSI status indicates congestion at the array controller.
If the array is being used by hosts (different LUNs for offline migration or LUNs under migration
for online migration), the increased concurrent I/Os have an adverse effect on the host I/O.
Thus, the MPX200 requires automated throttling while trying to maximize migration performance
by increasing concurrent I/Os. To control automatic throttling and pacing of migration I/O,
use the Enable I/O Pacing option. To achieve automated throttling, the MPX200
intelligently manages concurrent migration I/Os to maximize overall system throughput. If a
Queue Full
or Busy condition is detected, the MPX200 throttles the migration I/O until it
finds the condition of Queue Full or Busy condition. After the condition is cleared, the
MPX200 starts issuing more migration I/Os. This behavior maximizes host and migration I/O
performance.
The DM CLI allows you to change the Bandwidth for Migration, Maximum
Concurrent I/Os
, and Enable I/O Pacing settings only if the Target Type is either
Source or Src+Dest Target.
6.
At the Do you want to apply array license (yes/no) prompt, enter yes (the
default is no) to apply your changes.
The following shows an example of how to change the array properties in the CLI.
nl
MPX200 <1> (miguser) #> set array
A list of attributes with formatting and current values will follow.
Enter a new value or simply press the ENTER key to accept the current value.
If you wish to terminate this process before reaching the end of the list
press 'q' or 'Q' and the ENTER key to do so.
Index WWPN, PortId Symbolic Name Target Type
0 20:78:00:c0:ff:d5:9a:05, 00-00-00 HP MSA2012fc-0 Src+Dest
1 50:00:1f:e1:50:0a:e1:49, 82-07-00 HP HSV200-1 Src+Dest
2 50:06:01:60:4b:a0:35:de, 82-03-00 DGC RAID-2 Src+Dest
3 50:00:1f:e1:50:0a:37:18, 00-00-00 HP HSV210-3 Src+Dest
nl
Please select a Target Id from the list above ('q' to quit): 0
nl
Symbolic Name (Max = 128 characters) [HP MSA2012fc-0]
Target Type (1=SrcTarget, 2=DstTarget, 3=Src+Dest 4=None Target) [3 ]
Bandwidth for Migration (0=Array Bandwidth, 50-1600 MBps ) [0 ]
Maximum Concurrent I/Os (0=32, 1=64, 2=128, 3=256) [128 ]
Enable I/O Pacing (0=Enable, 1=Disable) [Disabled ]
Enable Load Balancing (0=Enable, 1=Disable) [Enabled ]
Array based licensed applied.
nl
All attribute values for that have been changed will now be saved.
If you have purchased array-based licenses and installed the licenses in the MPX200, follow these
steps to license a specific array for data migration. For every array that is licensed, one license is
consumed.
To apply an array-based license to a specific array in the CLI:
1.
Open a miguser session using the following command: miguser start -p migration.
2.
To apply a license, enter the following command:
nl
set array
, see
3.
At the prompt, Do you want to apply array license (yes/no), enter yes.
The following example shows the set array command.
108 Command line interface