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5.3 Affinity LPARs
On p690 systems, if you are running with more than one LPAR for each CEC, make sure you are
running affinity LPARs. To check affinity between CPU, memory, and HPS links, run the
associativity scripts on the LPARs.
To check the memory affinity setting, run the vmo command.
5.4 Small Real Mode Address Region on HMC GUI
Because the HMC and hypervisor code on POWER4 systems uses up physical memory, some
physical memory is unavailable to the LPARs. To make sure that Small Real Mode Address
Region on the HMC GUI is set on, make sure the ulimit –a output shows you all
unlimited.
Here are some examples of physical memory and available memory. Actual values depend on
your hardware configuration.
Physical Real Memory
Maximum Memory Available
64GB 61.5GB
128GB 120GB
256GB 240GB
512GB 495GB
5.5 Deconfigured L3 cache
The p690 and p655 systems can continue running if parts of the hardware fail. However, this can
lead to unexpectedly lower performance on a long-running job. One of the degradations observed
has been the deconfiguration of the L3 cache. To check for this condition, run the following
command on each LPAR to make sure that no L3 cache has been deconfigured:
/usr/lib/boot/bin/dmpdt_chrp > /tmp/dmpdt_chrp.out
vi /tmp/dmpdt_chrp.out
Search for L3 and
i-cache-size
08000000 [................]
d-cache-size
08000000 [................]
If you get a value other than the one above, then part or all of your L3 is deconfigured.
5.6 Service focal point
The Service Focal Point (SFP) application runs on the HMC and provides a user interface for
viewing events and performing problem determination. SFP resource managers monitor the
system and record information about serviceable events.