International Business Machines Corporation

Stephen G Wilkins

Mark P Gardiner

Matthew J Kalos

Harry M Yudenfriend

Clint Alan Hardy

Susan Kay Candelaria

Steven S Shultz

William Romney White

Hongjie Yang

Matthew J Rosato

Gustav E Sittmann, Iii

Frank William Brice

Donald W Schmidt

Charles W Gainey, Jr

Damian Leo Osisek

Janet R Easton

Ugochukwu Charles Njoku

Tan Lu

Robert Walter Schreiber

John W Yacynych

Harry M Yunderfriend

A computer-implemented method for transferring a reserve to a target host, according to one embodiment, includes granting to a source system, by a control unit, a reserve for a volume of a storage device. A push reserve command is received from the source system. The push reserve command specifies: a transfer of the reserve to a target system, parameter data identifying the target system, and path information specifying the source system. The reserve is transferred only to the target system in response to release of the reserve by the source system.

Methods for transferring reserves when moving virtual machines across systems

According to one embodiment, a host system includes logic adapted for receiving device information from a source system, logic adapted for building a virtual device based at least in part on the received device information, logic adapted for transferring a reserve of a storage device to the host system and/or receiving results of transferring the reserve to the host system, logic adapted for determining if the reserve is held by the host system, logic adapted for recording the reserve if the reserve is held by the host system, and logic adapted for sending a notification that the reserve is not held by the host system if the reserve is not held by the host system. Other systems and computer program products are also described according to various embodiments.

Systems and computer program products for transferring reserves when moving virtual machines across systems

According to one embodiment, a method includes receiving device information from a source system; building a virtual device on a host system based at least in part on the received device information; at least one of: transferring a reserve of a device stored on a storage device to a target system; and receiving results of transferring the reserve to the target system; determining if the reserve is held by the target system; recording the reserve if the reserve is held by the target system; and sending a notification that the reserve is not held by the target system if the reserve is not held by the target system. Other methods are also described according to various embodiments.

In an exemplary embodiment of this disclosure, a system may include a first hypervisor, a second hypervisor, and a shared memory set. The first hypervisor and the second hypervisor run over a single logical partition. The shared memory set is accessible by both the first hypervisor and the second hypervisor, and the first hypervisor is configured to communicate with the second hypervisor by writing to the shared memory. The second hypervisor may provide support for hardware that is not supported by the first hypervisor, which hardware may be accessed by the first hypervisor through communications facilitated by use of the shared memory.

Systems and methods to offload hardware support using a hypervisor subpartition

Embodiments relate to a method for encapsulating a virtual server in a hypervisor subpartition of a single logical partition to provide additional hardware support and advanced virtualization functions. An aspect includes running a first hypervisor and one or more additional hypervisors over a single logical partition. A request to manage a virtual server is received at the first hypervisor. The request is then analyzed to determine what resources are necessary to manage the virtual server. Based on the analyzed request, one of the first hypervisor or the one or more additional hypervisors is selected to complete the request.

Offloading service requests to a second guest hypervisor in a logical partition shared by a plurality of guest hypervisors

Parallel, coordinated, and optimized access of real Base and Alias DASDs by one or more virtual machines, each utilizing one or more virtual Base and Alias DASDs. Each of a plurality of virtual machines defines a virtual Base DASD device and a modified operating system may coordinate the virtual machine activity on real Base and Alias devices to maximize overall system throughput. In more complex embodiments, one or more virtual machines define one or more virtual Bases and associated virtual Alias devices in which case wherein the embodiments described coordinate their activity on one or more real Base and Alias devices to maximize overall system throughput.

Enabling parallel access volumes in virtual machine environments

A method for changing self-description data of a functional device in a computing system. The method may include virtualizing the functional device to create a virtual functional device, and adding, changing, or removing information in the self-description information sent from a functional device as a part of virtualization of the device by a hypervisor. Changing the self-description data of the functional device occurs after the self-description data has left the functional device.

Method and storage medium for virtualization of device self-description information using in-transit modification

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.

Growing community of inventors

Berkshire, NY, United States of America

Stephen G Wilkins