Hitachi Extended Remote Copy for Mainframe user guide (HITA738-96004, June 2008)

• Level 2 Threshold drop-down list:
Allows you to select the threshold for the sidefile for reporting SCP-SCI. This threshold is called the
SCP-SCI reporting threshold or the level-2 threshold. SCP is an acronym for State Change Pending.
SCI is an acronym for State Change Interrupt. The level-2 threshold must be within the range of
30 to 70 percent and must be a multiple of 10 percent (for example, 30, 40, 50, 60, or 70
percent). The default is 50 percent.
CAUTION:
The level-2 threshold is set to the area in which the SCP-SCI reporting threshold for XP Continuous
Access Asynchronous, TrueCopy Asynchronous z/OS, or Concurrent Copy. Keep in mind that
the level-2 threshold for XRC for Mainframe and the SCP-SCI reporting threshold for XP Continuous
Access Asynchronous, TrueCopy Asynchronous z/OS, or Concurrent Copy affect each other.
NOTE:
To calculate the level-1 threshold, subtract 10 percent from the level-2 threshold. To calculate the
level-3 threshold, add 10 percent to the level-2 threshold.
• Block Option:
Allows you to set IBM-compatibility mode for the device blocking function, or to control the amount
of write data according to sidefile capacity:
• Volume Level radio button:
Sets IBM-compatibility mode for the device blocking function. Write I/Os to logical volumes
will be put in a wait status by “Sleep” -”Wait” command retry if the amount of write data
exceeds the threshold for the number of recordsets per logical volume; the threshold is specified
by SDM, and the default threshold is 0x500.
NOTE:
If the Volume Level radio button is selected, Donot Block (Volume Level) is set to Enable. Also,
Level 1 Sleep and Level 2 Suspend are set to Disable.
• Cache Level radio button:
Depending on the sidefile capacity, the subsystem will perform one of the following three levels
of control of the amount of write data:
NOTE:
If the Cache Level radio button is selected, “Sleep” -”Wait” command retry will not be performed
according to the threshold for the number of recordsets per logical volume; the threshold is
specified by SDM.
Hitachi Extended Remote Copy for Mainframe user guide 37