Abstract: An approach to virtualizing a coherent memory hardware accelerator is provided comprising creating a segment table for a client logical partition (LPAR), wherein a virtual address space is reserved in the segment table, receiving an Input/Output (I/O) request to use the coherent memory hardware accelerator, generating an I/O operation associated with the I/O request, wherein the I/O operation is passed to the coherent memory hardware accelerator, receiving a map request from the coherent memory hardware accelerator, creating an entry in the reserved virtual address space in the segment table, creating a hardware page table map request for mapping a memory address associated with the client LPAR and returning the reserved virtual address space to the coherent memory hardware accelerator, wherein the coherent memory hardware accelerator has remote direct memory access to memory associated with the client LPAR for performing an acceleration of one or more processes.

Abstract: An approach for avoiding overloads of network adapters. The approach receives one or more requests from one or more virtual machines, wherein the one or more requests are directed to one or more network adapters. The approach determines whether a first network adapter of the one or more network adapters is saturated. Responsive to a determination that the first network adapter is saturated, the approach sends a first busy event to a first virtual machine of the one or more virtual machines.

Abstract: An approach for avoiding overloads of network adapters. The approach receives one or more requests from one or more virtual machines, wherein the one or more requests are directed to one or more network adapters. The approach determines whether a first network adapter of the one or more network adapters is saturated. Responsive to a determination that the first network adapter is saturated, the approach sends a first busy event to a first virtual machine of the one or more virtual machines.

Abstract: Embodiments include systems, methods, and computer program products to perform an operation for enabling multipath I/O for logical volume backed virtual disks through redundant virtual I/O servers (VIOSs) on a computing system. The operation generally includes creating, from a physical storage device, a logical volume on a first VIOS. The logical volume on the first VIOS is activated in a first access mode. The operation also includes importing the logical volume to a second VIOS. The logical volume on the second VIOS is activated in a second access mode different from the first access mode. The operation further includes mapping the logical volume on the first and second VIOSs as a backing storage device for at least one logical partition hosted on the computing system.

Abstract: An approach for avoiding overloads of network adapters. The approach receives one or more requests from one or more virtual machines, wherein the one or more requests are directed to one or more network adapters. The approach determines whether a first network adapter of the one or more network adapters is saturated. Responsive to a determination that the first network adapter is saturated, the approach sends a first busy event to a first virtual machine of the one or more virtual machines.

Abstract: An approach to virtualizing a coherent memory hardware accelerator is provided comprising creating a segment table for a client logical partition (LPAR), wherein a virtual address space is reserved in the segment table, receiving an Input/Output (I/O) request to use the coherent memory hardware accelerator, generating an I/O operation associated with the I/O request, wherein the I/O operation is passed to the coherent memory hardware accelerator, receiving a map request from the coherent memory hardware accelerator, creating an entry in the reserved virtual address space in the segment table, creating a hardware page table map request for mapping a memory address associated with the client LPAR and returning the reserved virtual address space to the coherent memory hardware accelerator, wherein the coherent memory hardware accelerator has remote direct memory access to memory associated with the client LPAR for performing an acceleration of one or more processes.

Abstract: An approach to virtualizing a coherent memory hardware accelerator is provided comprising creating a segment table for a client logical partition (LPAR), wherein a virtual address space is reserved in the segment table, receiving an Input/Output (I/O) request to use the coherent memory hardware accelerator, generating an I/O operation associated with the I/O request, wherein the I/O operation is passed to the coherent memory hardware accelerator, receiving a map request from the coherent memory hardware accelerator, creating an entry in the reserved virtual address space in the segment table, creating a hardware page table map request for mapping a memory address associated with the client LPAR and returning the reserved virtual address space to the coherent memory hardware accelerator, wherein the coherent memory hardware accelerator has remote direct memory access to memory associated with the client LPAR for performing an acceleration of one or more processes.

Abstract: Dynamic reconfiguration of queue pairs in a data processing system is provided. A device driver determines whether a dynamic CPU reconfiguration has added one or more CPUs to the data processing system, wherein the data processing system comprises a number of CPUs and a number of queue pairs. Responsive to the dynamic CPU configuration adding one or more CPUs, the device driver allocates a portion of a memory corresponding to a queue pair, wherein each queue pair comprises a receive queue and a transmit queue, programs a receive side scaling mechanism in a network adapter to allow for dynamic insertion of a processing engine associated with the queue pair, and enables transmit tuple hashing to the queue pair.

Abstract: According to one exemplary embodiment, a method for VIOS failover in an environment with a physical storage adapter is provided. The method may include assigning the physical storage adapter to a first VIOS, wherein the physical storage adapter has I/O connectivity to at least one storage device. The method may include configuring a first I/O path between the first VIOS and a second VIOS. The method may include configuring a second I/O path from a client partition to the first VIOS, wherein the second I/O path is set as a primary I/O path. The method may include configuring a third I/O path from the client partition to the second VIOS. The method may include determining the first VIOS is inaccessible. The method may include unassigning the physical storage adapter from the first VIOS. The method may include assigning the physical storage adapter to the second VIOS.

Abstract: In a method for communicating in a computing environment, a first computer establishing communication with a first virtual computer through a first virtual port using a primary port name for the first virtual port, wherein the first virtual computer is executing on a second computer. The first computer acquires an alternate port name for the first virtual port from the first virtual computer executing on the second computer. The first computer determines that the first virtual computer is not accessible using the primary port name for the first virtual port, wherein the first virtual computer is migrated to execute on a third computer. The first computer establishes communication with the first virtual computer executing on the third computer using the alternate port name of the first virtual port.

Abstract: In a method for communicating in a computing environment, a first computer establishing communication with a first virtual computer through a first virtual port using a primary port name for the first virtual port, wherein the first virtual computer is executing on a second computer. The first computer acquires an alternate port name for the first virtual port from the first virtual computer executing on the second computer. The first computer determines that the first virtual computer is not accessible using the primary port name for the first virtual port, wherein the first virtual computer is migrated to execute on a third computer. The first computer establishes communication with the first virtual computer executing on the third computer using the alternate port name of the first virtual port.

Abstract: According to one exemplary embodiment, a method for VIOS failover in an environment with a physical storage adapter is provided. The method may include assigning the physical storage adapter to a first VIOS, wherein the physical storage adapter has I/O connectivity to at least one storage device. The method may include configuring a first I/O path between the first VIOS and a second VIOS. The method may include configuring a second I/O path from a client partition to the first VIOS, wherein the second I/O path is set as a primary I/O path. The method may include configuring a third I/O path from the client partition to the second VIOS. The method may include determining the first VIOS is inaccessible. The method may include unassigning the physical storage adapter from the first VIOS. The method may include assigning the physical storage adapter to the second VIOS.

Abstract: Dynamic reconfiguration of queue pairs in a data processing system is provided. A device driver determines whether a dynamic CPU reconfiguration has added one or more CPUs to the data processing system, wherein the data processing system comprises a number of CPUs and a number of queue pairs. Responsive to the dynamic CPU configuration adding one or more CPUs, the device driver allocates a portion of a memory corresponding to a queue pair, wherein each queue pair comprises a receive queue and a transmit queue, programs a receive side scaling mechanism in a network adapter to allow for dynamic insertion of a processing engine associated with the queue pair, and enables transmit tuple hashing to the queue pair.

Abstract: Dynamic reconfiguration of queue pairs in a data processing system is provided. A device driver determines whether a dynamic CPU reconfiguration has added one or more CPUs to the data processing system, wherein the data processing system comprises a number of CPUs and a number of queue pairs. Responsive to the dynamic CPU configuration adding one or more CPUs, the device driver allocates a portion of a memory corresponding to a queue pair, wherein each queue pair comprises a receive queue and a transmit queue, programs a receive side scaling mechanism in a network adapter to allow for dynamic insertion of a processing engine associated with the queue pair, and enables transmit tuple hashing to the queue pair.

Abstract: Dynamic reconfiguration of queue pairs in a data processing system is provided. A device driver determines whether a dynamic CPU reconfiguration has added one or more CPUs to the data processing system, wherein the data processing system comprises a number of CPUs and a number of queue pairs. Responsive to the dynamic CPU configuration adding one or more CPUs, the device driver allocates a portion of a memory corresponding to a queue pair, wherein each queue pair comprises a receive queue and a transmit queue, programs a receive side scaling mechanism in a network adapter to allow for dynamic insertion of a processing engine associated with the queue pair, and enables transmit tuple hashing to the queue pair.

Abstract: A method is disclosed for retrieving the reservation status information of a storage area network (SAN) device, a host transmits a persistent reservation in command with service action setting of ‘read reservation’ to a first LUN, wherein the host is connected to a port of the data storage server to which the LUN belongs. The host receives a message from the LUN. The host determines that the message is a success. The host sends to the LUN a persistent reservation in command with service action setting of ‘read keys’, responsive to a success message. The host determines that the LUN responds with a zero data length. The host determines the LUN is reserved with type 2 reservation, responsive to a determination that the LUN responds with a non-zero data length.

Abstract: A technique for operating a storage area network includes detecting an input/output operation failure associated with a logical unit number, which is associated with a first target port. The technique also includes determining, subsequent to the detected input/output operation failure, whether the logical unit number is associated with a second target port. Finally, the technique includes routing subsequent input/output operations for the logical unit number to the logical unit number via the second target port, in response to determining that the logical unit number is associated with the second target port.

Abstract: According to one exemplary embodiment, a method for VIOS failover in an environment with a physical storage adapter is provided. The method may include assigning the physical storage adapter to a first VIOS, wherein the physical storage adapter has I/O connectivity to at least one storage device. The method may include configuring a first I/O path between the first VIOS and a second VIOS. The method may include configuring a second I/O path from a client partition to the first VIOS, wherein the second I/O path is set as a primary I/O path. The method may include configuring a third I/O path from the client partition to the second VIOS. The method may include determining the first VIOS is inaccessible. The method may include unassigning the physical storage adapter from the first VIOS. The method may include assigning the physical storage adapter to the second VIOS.

Abstract: According to one exemplary embodiment, a method for VIOS failover in an environment with a physical storage adapter is provided. The method may include assigning the physical storage adapter to a first VIOS, wherein the physical storage adapter has I/O connectivity to at least one storage device. The method may include configuring a first I/O path between the first VIOS and a second VIOS. The method may include configuring a second I/O path from a client partition to the first VIOS, wherein the second I/O path is set as a primary I/O path. The method may include configuring a third I/O path from the client partition to the second VIOS. The method may include determining the first VIOS is inaccessible. The method may include unassigning the physical storage adapter from the first VIOS. The method may include assigning the physical storage adapter to the second VIOS.

Abstract: A method for selecting a path control module (PCM) for a logical unit number (LUN) associated with a host enabled to support multiple PCMs is provided. The method may include selecting a PCM associated with the LUN from a plurality of supported PCMs. The method may also include creating an entry in a configuration database or a configuration file associated with the host, whereby the entry maps the selected PCM with a unique ID associated with the LUN. The method may further include determining a unique ID associated with a hard disk. The method may include matching the unique ID with the created entry. The method may include selecting the PCM from the matched entry based on the matching. Additionally, the method may include loading a kernel extension corresponding to the selected PCM. The method may include configuring the LUN using the loaded kernel extension corresponding to the selected PCM.