HP XP7 Storage - Manual (Page 9)

Supported XRC functions in XRC2 and XRC3
The following table lists the supported Compatible XRC features in IBM XRC functions (XRC2 and
XRC3).
XRC3 XRC2 Description Feature
Supported Supported Sidefile threshold tuning feature for each volume. DEV blocking
Supported Not supported Differential copy feature for unplanned outage achieved
by the differential bit management in the storage system. Unplanned outage
Supported Not supported Alternate path retry feature for CNT USD
1
connections. CNT MULTI path
Supported
2
Not supported Fix or Float of Utility DEV setting feature. Fix utility
Supported
3
Not supported Suspend setting feature which does not report SCP from
SDM. Suspend on Long
Busy
Supported
4
Not supported Feature to set arbitrary Sleep Time from SDM when the
amount of write data is controlled. Write Pacing
Supported
5
Not supported This function enables SDM to read the sidefile parallel
using the primary session and its auxiliary sessions in the Multiple Reader
primary storage control session. It reduces data stagnation
of the sidefile compared with ordinary Single Reader.
Supported Not supported This function is used to reduce the handshake time to
connect the channel and control unit, and then uses the Extended Distance
FICON
extended IU Pacing protocol to maintain the long distance
communication status.
Notes:
1. CNT extender (Ultranet Storage Director).
2. Only Fix of Utility DEV is supported (Float is not supported).
3. Operates when Level 2 Suspend is set to Disabled in the option of Compatible XRC. Level 2 Suspend operation
will be processed preferentially, when Level 2 Suspend is set to Enable.
4. Operates when Block Option is set to Volume Level in the option of Compatible XRC. Write Pacing will not operate
when Block Option is set to Cache Level.
5. Functioning on DKC emulation type I-2107 and later.
6. Install Parallel Access Volumes or Hyper Parallel Access Volumes, if you use this function. See (page 17) , when you
use Hyper Parallel Access Volumes.
When the controller emulation type is I-2107, both XRC2 and XRC3 are supported.
Number of sessions for Compatible XRC and CC
The following table shows the number of supported sessions in Compatible XRC.
Number of Sessions Unit
Number of CUs x 64 Per storage system
64* Per CU
1 Per volume
*Primary and auxiliary sessions are assigned when Multiple Reader function is used. The number of auxiliary sessions
is a parameter of NumberReaderTasks which is defined in a XRC PARMLIB data set. This parameter defines multiplicity
of auxiliary sessions on a primary session. For example, the following example shows that the three auxiliary sessions
are enabled and multiply on a primary session.
NumberReaderTasks *,4
Set up and requirements 9