What has changed since Itanium? What counts as a logical NonStop CPU now? As I (mis?)understand it, under Itanium a physical server blade was called a slice. It had multiple CPU sockets (called Processing Elements) and memory on the was partitioned with MMU mapping and Itanium security keys so each Processing Element could only access a portion of it. All IO on a Processing Element went out over ServerNet (or Infiniband) to a pair of Logical Sync Units, and was checked/compared with IO from another Processing Element running the same code on a different physical server blade. The 2 (or 3) processing elements combined to form a single logical CPU. I wonder if this is still the case? I believe there was a follow on (I assume when Itanium went multi-core) called NonStop Multicore Architecture, but I haven't found a paper on it.
Also, I'm curious how the Disk Process fits in with Storage Clustered IO Modules(CLIMs)? Do CLIMs just act as a raw disk, with the Disk Process talking to it like they would use to talk to a locally attached disk? Or is there more integration with the CLIM - like a portion of the Disk Process has been ported to Linux, or has Enscribe been ported to run on the CLIMs.
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What has changed since Itanium? What counts as a logical NonStop CPU now? As I (mis?)understand it, under Itanium a physical server blade was called a slice. It had multiple CPU sockets (called Processing Elements) and memory on the was partitioned with MMU mapping and Itanium security keys so each Processing Element could only access a portion of it. All IO on a Processing Element went out over ServerNet (or Infiniband) to a pair of Logical Sync Units, and was checked/compared with IO from another Processing Element running the same code on a different physical server blade. The 2 (or 3) processing elements combined to form a single logical CPU. I wonder if this is still the case? I believe there was a follow on (I assume when Itanium went multi-core) called NonStop Multicore Architecture, but I haven't found a paper on it.
Also, I'm curious how the Disk Process fits in with Storage Clustered IO Modules(CLIMs)? Do CLIMs just act as a raw disk, with the Disk Process talking to it like they would use to talk to a locally attached disk? Or is there more integration with the CLIM - like a portion of the Disk Process has been ported to Linux, or has Enscribe been ported to run on the CLIMs.
The same thing with how Networking CLIMs fit in.