IBM pSeries Affinity LPARs, Small Real Mode Address Region on HMC GUI, Deconfigured L3 cache

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 –aoutput 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.

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