Fujitsu Siemens Computers SPARC Enterprise M4000, User Manual

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Chapter 2 What You Must Know Before Using DR 2-7
When the kernel cage is enabled, kernel memory is assigned to system boards in the
order of their address spaces. The kernel cage begins in the first address space
(which initially corresponds to the non-floating board with the lowest LSB number).
If the kernel requires more memory, then the kernel cage expands to the next
address space (which initially corresponds to the non-floating board with the next-
lowest LSB number), and so on. The kernel cage extends into the address spaces of
floating boards only if kernel memory is too large to fit in the address spaces of the
non-floating boards.
Note – During a copy-rename operation, the address spaces initially assigned by
POST are exchanged between system boards. The effects of this process persist
through reboots of a domain. Therefore, kernel memory may be assigned in a
seemingly different order until the domain has gone through a full
poweroff
(8) and
poweron
(8) cycle, as this pair of operations cancels the effects of copy-rename
operations.
For details on assigning LSB numbers to system boards, see the ' SPARC Enterprise
M4000/M5000/M8000/M9000 Servers XSCF User’s Guide ' or the
setdcl
(8) man page.
(1.4) Copy-rename
Kernel memory itself cannot be removed, but it can be transferred to another system
board. A DR operation to delete a kernel memory board must first perform this
transfer, which is called a copy-rename operation.
The Solaris OS selects the target for the copy-rename operation from among the
available user memory boards. The following selection and preference criteria are in
effect:
■
The copy-destination board must not yet contain any kernel memory. (It must be
a user memory board.)
■
The copy-destination board must not be a floating board, unless the
-f
(force)
option is used with the
deleteboard
(8) command.
■
The copy-destination board must contain at least as much physical memory as the
system board being deleted.
■
If more than one system board satisfies all the selection criteria to the same degree
of satisfaction, the one with the lowest LSB number is selected as the copy-
destination board.
Note – If no system boards meet the selection criteria, the DR operation to delete
the kernel memory board will fail.