IBM Support in Germany After End of Life

Where Memory Sits Relative to the Processor Matters

On a Power frame, a partition performs best when the memory allocated to it is physically close to the processors it has been given. Access to memory on the same node is faster than access across nodes, and the hypervisor tries to allocate with that in mind. The allocation it can achieve depends on what is free at the moment the request is made.

Every Resize Fragments the Layout a Little

Dynamic reconfiguration is one of the strengths of the platform: processors and memory can be added and removed while partitions run. Each of those operations, however, takes whatever resources are available at that instant, which over years of growth and rebalancing produces an allocation progressively more scattered than the clean one the partition started with. Nothing fails and no operation is wrong; the layout simply degrades.

A gradual slowdown with no event to point at

German operators bring this to us as a partition that has become slower over several years with no change in workload and no incident to anchor it to. That profile fits many explanations, which is why it is rarely diagnosed: there is no failure, no alert and no date. The partition has been correct throughout and has simply been spending more of its time waiting for memory.

There is a number for it

The platform reports an affinity or locality score per partition, which turns this from an inference into a measurement. A score well away from ideal is direct evidence, and correcting it normally means restarting the partition so the hypervisor can lay the allocation out cleanly. That is an outage, so the sensible order is to read the score, decide whether it explains what you are seeing, and only then schedule the restart.

What ICD Supplies for IBM Estates in Germany

Memory ordered so a partition can be laid out close to its processors, processor modules whose locality relative to that memory decides latency, System x components, ServeRAID adapters with the battery or capacitor hardware they require, and redundant supplies for frames the authorised channel no longer serves. Where the affinity score explains a slowdown we will say so before quoting hardware. Germany is on the European card at 3 to 5 days door-to-door from Cairo. Each item is proven on test, serial-tied, and covered one to three years.