International Business Machines Corporation

Tan Lu

Leslie W Wyman

Harry M Yudenfriend

Kenneth J Oakes

John S Trotter

Dale Francis Riedy, Jr

Scott M Carlson

William J Rooney

Greg A Dyck

Janet R Easton

Charles W Gainey, Jr

Frank William Brice

Jeffrey Paul Kubala

Charles E Shapley

Marten J Halma

Hans-Helge Lehmann

Damian Leo Osisek

Richard P Tarcza

Brenton F Belmar

Gustav E Sittmann, Iii

Steven G Glassen

Beth A Glendening

Allan Samuel Meritt

Ugochukwu Njoku-Charles

Donald W Schmidt

David F Craddock

Giles R Frazier

Daniel Francis Casper

Robert J Dugan

Eugene P Hefferon

Ugochukwu Charles Njoku

Carol B Hernandez

Stephen G Wilkins

Robert A Smith

David W Hollar

Ugochukwo Njoku-Charles

Michael G Melendy

An Extended Input/output (I/O) measurement word facility is provided. Provision is made for emulation of the Extended I/O measurement word facility. The facility provides for storing measurement data associated with a single I/O operation in an extended measurement word associated with an I/O response block. In a further aspect, the stored data may have a resolution of approximately one-half microsecond.

Extended input/output measurement word facility for obtaining measurement data in an emulated environment

Extended input/output measurement word facility for obtaining measurement data

Extended input/output measurement word facility and emulation of that facility

A method, system, program product and computer data structure for providing for two levels of server virtualization. A first hypervisor enables multiple logical partitions to share a set of resources and provides a first level of virtualization. A second hypervisor enables multiple, independent virtual machines to share the resources that are assigned to a single logical partition and provides a second level of virtualization. All events for all of the virtual machines within said single logical partition are grouped into a single partition-owned event queue for receiving event notifications from the shared resources for that single logical partition. A request for an interrupt is signaled for the grouped events from the partition-owned event queue for the demultiplexing of grouped events, by the machine, from the partition-owned event queue into individual, virtualized event queues that are allocated on a per virtual machine basis.

Demultiplexing grouped events into virtual event queues while in two levels of virtualization

Extended input/output measurement word facility, and emulation of that facility

An Extended Input/output (I/O) measurement block facility is emulated. The facility provides for the collection of relevant I/O measurement data, and the storing for later efficient retrieval of that data in an extended measurement block. The stored data relates to the performance of an I/O subchannel.

Emulation of extended input/output measurement block facilities

An input/output subsystem is configured as a plurality of input/output subsystem images, each of which appears to a program as an independent input/output subsystem. An input/output subsystem image is identified by an input/output subsystem image identifier, which is used by various programs to designate the particular input/output subsystem image for which an I/O operation is to be performed. An input/output subsystem image includes, for instance, one or more input/output paths. An input/output path of an input/output subsystem image is identified by an input/output path identifier, as well as a physical input/output path identifier.

Multiple logical input/output subsystem facility

Input/output interruptions are managed in computing environments that do not use dedicated per-guest interruption hardware to present interruptions. Dispatchable guest programs in the environment receive I/O interruptions directly without hypervisor intervention. This is facilitated by using one or more interruption controls stored in memory and associated with each guest program. For those guest programs that are not currently dispatchable, interruptions can be posted for the guests and notifications to the hypervisor can be aggregated. The hypervisor can then process a plurality of notifications for the plurality of guests in a single invocation.

Managing input/output interruptions in non-dedicated interruption hardware environments

I/O measurement data for channels attached to logical control unit queues is obtained related to a plurality of logical control unit queues. A store secondary queue measurement data instruction specifies a range of queues for which extended secondary measurement blocks derived from the I/O measurement data are stored at a memory address specified by the store secondary queue measurement data instruction.

Obtaining extended queue measurement data for a range of logical control unit queues

Managing input/output interruptions in non-dedicated interruption hardware environments, and methods therefor

An Input/output (I/O) measurement block facility is provided that creates subchannel measurement blocks (comprising device busy values) related to performance of an I/O operation of a subchannel, wherein a device busy time value is a sum of time intervals when the subchannel is device busy during an attempt to initiate any one of a start function or a resume function at the subchannel.

Extended input/output measurement block

Growing community of inventors

Poughkeepsie, NY, United States of America

Tan Lu