IBM Z10 EC manual Transparent Sparing, Plan Ahead Memory

and provide the clock signal to the system transparently, with no system outage. Previously, in the event of a failure of the active oscillator, a system outage would occur, the subsequent system Power On Reset (POR) would select the backup, and the system would resume operation. Dynamic Oscillator Switchover is exclusive to System z10 EC and System z9.

Transparent Sparing

The z10 EC offers two PUs reserved as spares per server. In the case of processor failure, these spares are used for transparent sparing. On z10 EC sparing happens on a core granularity rather than chip granularity as on z990 and System z9 (for which “chip” equaled “2 cores”).

Concurrent Maintenance

Concurrent Service for I/O features: All the features that plug into the I/O Cage are able to be added and replaced concurrent with system operation. This virtually eliminates any need to schedule outage for service to upgrade the I/O subsystem on this cage.

Upgrade for Coupling Links: z10 EC has concurrent maintenance for the ISC-3 daughter card. Also, Coupling Links can be added concurrently. This eliminates a need for scheduled downtime in the demanding sysplex envi- ronment.

Cryptographic feature: The Crypto Express2 feature plugs in the I/O cage and can be added or replaced con- currently with system operation.

Redundant Cage Controllers: The Power and Service Control Network features redundant Cage Controllers for Logic and Power control. This design enables non-disrup- tive service to the controllers and virtually eliminates cus- tomer scheduled outage.

Auto-Switchover for Support Element (SE): The z10 EC has two Support Elements. In the event of failure on the Primary SE, the switchover to the backup is handled automatically. There is no need for any intervention by the Customer or Service Representative.

Concurrent Memory Upgrade

This function allows adding memory concurrently, up to the maximum amount physically installed. In addition, the Enhanced Book Availability function also enables a memory upgrade to an installed z10 EC book in a multi- book server.

Plan Ahead Memory

Future memory upgrades can now be preplanned to be non-disruptive. The preplanned memory feature will add the necessary physical memory required to support target memory sizes. The granularity of physical memory in the System z10 design is more closely associated with the granularity of logical, entitled memory, leaving little room for growth. If you anticipate an increase in memory require- ments, a “target” logical memory size can now be speci-

fied in the confi guration tool along with a “starting” logical memory size. The confi guration tool will then calculate the physical memory required to satisfy this target memory.

Should additional physical memory be required, it will be fulfi lled with the currently available preplanned memory features.

The preplanned memory feature is offered in 16 gigabyte (GB) increments. The quantity assigned by the confi gu- ration tool is the number of 16 GB blocks necessary to increase the physical memory from that required for the “starting” logical memory to the physical memory required for the “target” logical confi guration. Activation of any pre- planned memory requires the purchase of a preplanned

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