HP StorageWorks XP Remote Web Console Software - Manual (Page 25)

Table 3 Sidefile Thresholds (continued)
Action(s) Threshold(s) Operation
Modes for TrueCopy for Mainframe”
(page 12)
).
MCU (RCU) reaches threshold (70%):
command retry to host (MCU), max Sidefile threshold of MCU = 30-70%
of cache, default = 50%.
delay time (500 or 100 ms). Delay time
TrueCopy for Mainframe
Asynchronous threshold can be
can be adjusted using mode 93 (see
“XP Disk Array Modes for TrueCopy for
Mainframe” (page 12)
).
adjusted from 30-70% (in 10%
increments) using the TrueCopy for
Mainframe software.
MCU (RCU) reaches puncture: suspend
affected TrueCopy for Mainframe Puncture threshold = sidefile threshold
+ 10%
Asynchronous pairs due to sidefile
overflow condition.
Threshold 1 = command retry. [XRC+CC sidefile] / [avail cache] =
40%, 50%, 60% Compatible XRC
*
Threshold 2 = SCP message.
XRC+CC thresholds can be adjusted
by using modes 85 and 86 (see
“XP
Threshold 3 = puncture condition.
Disk Array Modes for TrueCopy for
Mainframe” (page 12)
).
Threshold 1/2/3 = 30/40/50%,
40/50/60%, or 60/70/80%
Threshold 1 = no action. [XRC+CC sidefile] / [avail cache] =
40%, 50%, 60% CC
Threshold 2 = SCP message.
XRC+CC thresholds can be adjusted
by using modes 85 and 86 (see
“XP
Threshold 3 = puncture condition.
Disk Array Modes for TrueCopy for
Mainframe” (page 12)
).
Threshold 1/2/3 = 30/40/50%,
40/50/60%, or 60/70/80%
Command retry. [write pending] / [avail cache -
sidefile] = 70% Write Pending
NOTE: For further information on sidefile thresholds for Compatible XRC operations, see Appendix
“TrueCopy for Mainframe Load Balancing and Sidefile Management and Control” (page 251) .
Graduated Delay Sidefile Management
“Graduated Delay Process for Sidefile Management” (page 26) shows the graduated delay process
for TrueCopy for Mainframe sidefile management. When the sidefile value reaches the high-water
mark (threshold minus 20%), the HP disk array begins command retry delay for host updates to
TrueCopy for Mainframe M-VOLs and reports a warning SIM to the host. As the amount of sidefile
increases, the delay increases incrementally as shown in
“Graduated Delay Process for Sidefile
Management” (page 26) . Mode 93 on the XP (see “XP Disk Array Modes for TrueCopy for
Mainframe” (page 12) ) allows you to select the delay type (long or short). This graduated delay
methodology minimizes the potential for sidefile overcommitment, while at the same time providing
another level of automation control.
If there is a network problem, lack of bandwidth, or lack of sufficient Fibre links, the sidefile will
grow and the microcode will add delay to host I/O until the sidefile goes below a certain level
again. Disabling this function will cause the pairs to suspend.
TrueCopy for Mainframe Async Recordset Operations 25