Initial Copy Pace For Calculating Initial Copy Response Time; Example Settings - HP StorageWorks XP12000 User Manual

Round Trip Time = Round Trip Time between MCU-RCU x 2
For the Round Trip Time between the MCU and RCU, contact your carrier or use the ping command and
so on to measure the time. If you do not use lines and so on between the MCU and RCU, specify 1.
Initial copy response time is the response time required for multiple initial copy operations. Use the
following formula to calculate the initial copy response time. To obtain the time, use the following values:
• Initial copy pace
• Maximum number of initial copy VOLs
• Speed of the line between the MCU and RCU
• Number of lines
Initial Copy response time (ms) = (1[MB] / "Speed of line between
Table 24 Initial copy pace for calculating initial copy response time
Operation
Table 25 Example settings
Item No.
1
2
3
Registering RCUs to the connected MCU
1.
Ensure that remote copy connections and MCU ports are properly configured. Get the S/N of
the RCU and the SSIDs for the CU image in the RCU. The register RCU operation fails without
this information. The disk array should have a label or tag indicating its S/N and SSIDs. The
1
Data transfer between the MCU and RCU involves two response sequences per command issued. Therefore, you must
double the Round Trip Time between the MCU and RCU.
2
When you connect the MCU and RCU without lines and so on, specify 0.17[MB/ms] in "Speed of line between MCU and
RCU."
3
For "initial copy pace" in the formula, see
4
For maximum number of initial copy volumes, see
5
Even if "Max number of initial copy VOLs" / "Number of lines between MCU-RCU" is larger than 16, specify "Max number
of initial copy VOLs" / "Number of lines between MCU-RCU" as 16.
+ Initial Copy response time (ms)
RAID Manager
Command View XP
or XP Remote Web
Console
Round trip Line speed
time [ms] between
MCU/RCU
[MB/ms]
0 0.1
30 0.1
100 0.1
Table
MCU-RCU[MB/ms]")
x ("initial copy pace" / 15)
x ("max number of initial copy VOLs"
/ "Number of lines between MCU-RCU")
Perform initial Perform initial copy and update copy
copy only at one time
Initial copy pace
specified at time
of pair creation is
1 to 8
Initial copy pace Initial copy pace
specified when pair specified when pair
was created was created
Initial copy pace Initial copy pace
specified when pair specified when pair
was created was created
Number Initial copy
of lines pace
between
MCU/RCU
4 15
15
4
15
4
24.
Changing subsystem settings. The default is 64.
1
2,
3,
4,
Initial copy pace
specified at time
of pair creation is
9 to 15
8
8
Maximum
Round
number of
trip time
initial copy
specified
VOLs
[ms]
64 160
220
64
360
64
Continuous Access XP user guide
5
77