Memory Boot-Time Deconfiguration (Memory Repeat Gard) - IBM RS/6000 44P 270 Service Manual

Memory Boot-Time Deconfiguration (Memory Repeat Gard)

Memory boot time deconfiguration allows for the removal of a memory segment or
DIMM from the system configuration at boot time. The objective is to minimize system
failures or data integrity exposure due to faulty memory hardware. The hardware
resource(s) to be removed are the ones that experienced the following failures:
v A boot-time test failure.
v Run-time recoverable errors over the error threshold prior to the current boot phase.
v Run-time irrecoverable errors prior to the current boot phase.
This function uses firmware power-on self-test (POST) to discover and isolate memory
hardware failures during boot time. It also uses the hardware error detection logic in the
memory controller to capture run-time recoverable and irrecoverable errors. The
firmware uses the error signatures in the hardware to analyze and isolate the error to
the specific memory segment or DIMM.
The memory segment or DIMM that is deconfigured remains off-line during subsequent
reboots until the faulty memory hardware is replaced.
The function allows users to manually deconfigure or re-enable a previously
deconfigured memory segment/DIMM through the service processor menu. The user
can also enable or disable this function through the service processor menu.
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Service Guide