Abstract: A network switch, in response to receipt from a source station of a Layer 2 reservation request, establishes a reservation for capacity of an ingress queue of the network switch for a data flow of the source station. In response to a queue overrun condition on the ingress queue of the network switch while the reservation is active, the network switch preserves data frames in the data flow of the source station transmitted pursuant to the reservation and discards other data frames.

Abstract: A computer implemented method, apparatus, and computer usable program code for managing a software partition in logical partitioned data processing system. A virtual root process is created for the software partition, wherein the virtual root process functions as a root process for the software partition. The set of child processes is re-parented to the virtual root process in response to termination of a process having a set of child processes.

Abstract: In some example embodiments, there is a method for failback to a primary communications adapter. The method includes receiving, in a driver for the primary communications adapter and a backup communications adapter, a link up event for the primary communications adapter, wherein the link up event is sent from the primary communications adapter to the driver, and wherein the link up event is triggered by establishing electrical connectivity to the primary communications adapter. The method includes inferring that the primary communications adapter is configured for receiving packets. The method includes setting the backup communications adapter to idle, wherein the backup communications adapter receives packets and drops the packets while idle. The method includes activating the primary communications adapter, wherein the primary communications adapter receives packets and passes the packets up a protocol stack while activated.

Abstract: In one embodiment a method for migrating a workload from one processing resource to a second processing resource of a computing platform is disclosed. The method can include a command to migrate a workload that is processing and the process can be interrupted and some memory processes can be frozen in response to the migration command. An index table can be created that identifies memory locations that determined where the process was when it is interrupted. Table data, pinned page data, and non-private process data can be sent to the second processing resource. Contained in this data can be restart type data. The second resource or target resource can utilize this data to restart the process without the requirement of bulk data transfers providing an efficient migration process. Other embodiments are also disclosed.

Abstract: Methods, systems, and program products are provided for failback to a primary communications adapter. Embodiments of the present invention include receiving, in a driver for a primary communications adapter and a backup communications adapter, a link up event for the primary communications adapter; inferring that the primary communications adapter is capable of receiving packets; setting the backup communications adapter to idle; and activating the primary communications adapter. In typical embodiments, the primary communications adapter includes a plurality of linked communications adapters comprising an EtherChannel pseudo-adapter.

Abstract: A computer implemented method, apparatus, and computer usable program code for managing a software partition in logical partitioned data processing system. A virtual root process is created for the software partition, wherein the virtual root process functions as a root process for the software partition. The set of child processes is re-parented to the virtual root process in response to termination of a process having a set of child processes.

Abstract: A computer implemented method, apparatus, and computer program product for dynamically loading a module into an application address space. In response to receiving a checkpoint signal by a plurality of threads associated with an application running in a software partition, the plurality of threads rendezvous to a point outside an application text associated with the application. Rendezvousing the plurality of threads suspends execution of application text by the plurality of threads. The application text is moved out of an application address space for the application to form an available application address space. The available application address space is an address space that was occupied by the application text. A software module is moved into the available application address space.

Abstract: An operating system manages virtualized instances of hardware resources and migration enabled applications partitioned into one of multiple partitions with a separate operating system kernel running in each of the partitions. A migration event controller of the operating system manages the checkpoint and restart process during migration of a virtualized instance of at least one migration enabled application from a departure partition to an arrival partition. The migration event controller supports migration enabled applications to separately specify at least one application specific checkpoint script and restart script to be triggered by checkpoint and restart events by the migration event controller so the at least one migration enabled application can participate in performing the checkpoint and restart process for additional state information during migration of the virtualized instance from the departure partition to the arrival partition.

Abstract: In a computer system divided into multiple separate workload partitions, wherein at least one of the partitions contains multiple applications, and a loopback interface is made available to each partition, a method is provided for routing packets from one application to another application. In one embodiment of the invention, each packet to be routed from one application to another application in the same home partition comprises a first packet, and all other packets comprise second packets. The method comprises the steps of assigning the same pre-specified IP address to each of the first packets, and routing each of the first packets from its home partition to a loopback interface at the IP network processing layer. The method further includes marking the first packets to identify the home partition of each first packet, and directing the marked first packets to a mechanism configured to deliver each first packet only to its home partition, in response to the markings.

Abstract: A method, computer program product, and data processing system for performing efficient communication between software entities residing in the same operating system using conventional network communications APIs are disclosed. According to a preferred embodiment, when a software entity (e.g., a process) attempts to communicate through a networking API, the operating system determines whether the other end of the communication refers to the same hardware node. If so, the operating system replaces the network protocol connection (socket connection) with a direct interprocess communication construct. The operating system provides additional code to simulate the appearance of an actual network (socket) connection at the API level while performing all actual I/O using the interprocess communication construct.

Abstract: A method, data processing system, and computer usable code are provided for protocol definition for software bridge failover. In a first aspect of the present invention, a first software bridge determines the proper working operation of a physical adapter. Limbo packets are sent to a second software bridge alerting the second software bridge that the first software bridge is no longer bridging traffic responsive to the physical adapter failure in the first software bridge. The second software bridge receives the limbo packets, and, in response to receiving the limbo packets, asserts primary control and initiates bridging of traffic. In an alternative aspect of the present invention a first software bridge sends keep-alive packets. A second software bridge monitors the keep-alive packets from the first software bridge and, in response to a failure to detect the keep-alive packets from the first software bridge, the second software bridge initiates bridging of traffic.

Abstract: A method, system and computer program product for transitioning network traffic between logical partitions in one or more data processing systems are disclosed. The method includes defining a plurality of logical partitions with respect to one or more processing units of one or more data processing systems and dynamically reallocating resources from a second partition to a first partition among the plurality of logical partitions. Packets awaiting processing are transferred from the second partition to the first partition and processed on the first partition.

Abstract: A method, system and apparatus for improving data transfer rate over a network are provided. When a piece of data is to be transmitted to a target system, it is divided into a number of packets and a determination is made as to whether the number of packets exceeds a threshold number. If so, the packets are transferred in parallel over a plurality of network connections. The ideal network connections are TCP/IP connections. Thus, each packet has an IP header, which contains an IP identification field. An indicium is placed into the IP identification field for proper reconstruction of the data by the target system.

Abstract: A computer implemented method, apparatus, and computer program product for transferring a privilege to a module. In one embodiment, a set of privileges required to initiate execution of code associated with the software module is identified to form enhanced privileges. The application is frozen. The enhanced privileges are unassigned to the application and the application has insufficient privileges to initiate execution of code associated with the software module. The software module is loaded into available application address space associated with the application. The enhanced privileges are transferred to the application. Execution of the application is unsuspended and the code associated with the software module is executed within the application.

Abstract: An apparatus and method for an improved bulk read socket call are provided. With the apparatus and method, a new field, so_rcvlen, is added to the socket structure that identifies the bulk read size requested by the user. The kernel of the prior art recv( ) function is also modified so that it sets the so_rcvlen to the size requested by the user prior to the recv( ) function going to sleep and waiting for the full data size requested by the user. A new flag, SP_MSGWAITALL, is also provided in the socket structure. In the TCP input processing, when data is received for a particular socket, the current setting of the SP_MSGWAITALL is checked. If the SP_MSGWAITALL flag is set, it is determined whether the amount of data stored in the socket receive buffer is less than the value of so_rcvlen. If not, the TCP input processing does not wake up the recv( ) thread. However, for every alternate segment, the TCP input processing sends back an acknowledgment (ACK).

Abstract: Exemplary embodiments provide a computer implemented method, apparatus, and computer-usable program code for moving a software partition from an origination network file system client data processing system to a destination network file system client data processing system. Responsive to receiving a request to perform a checkpoint operation on a software partition, network file system related mount information for the software partition is gathered. Determined ports of a network are unblocked. Unwritten data on the origination network file system client data processing system is synchronized with a remote network file system server. The network is re-blocked. A checkpoint file is generated and stored. The checkpoint file is sent to the destination network file system data processing system.

Abstract: A computer implemented method, data processing system, and computer program product for enabling network statistics to be collected per software partition. When an incoming data packet is received at the Internet Protocol (IP) layer of an operating system, the IP address in the incoming data packet is identified. The IP address in the incoming data packet is then compared against IP addresses stored in a hash table, wherein the hash table maps each IP address in the hash table to a software partition of the operating system. If an IP address in the hash table matches the IP address in the data packet, the software partition mapped to the located IP address in the hash table is identified. Network statistics collected for the incoming data packet are then associated with the software partition.

Abstract: A host enables any adapter of multiple adapters of the host to concurrently support any VIPA of the multiple VIPAs assigned to the host. Responsive to a failure of at least one particular adapter from among the multiple adapters, the host triggers the remaining, functioning adapters to broadcast a separate hardware address update for each VIPA over the network, such that for a failover in the host supporting the multiple VIPAs the host directs at least one other host accessible via the network to address any new packets for the multiple VIPAs to one of the separate hardware addresses of one of the remaining adapters.

Abstract: A method, system, and program are provided for managing a response to an email by a hidden email recipient. A hidden recipient manager detects a request to respond to an electronic communication by a hidden recipient of that electronic communication from among a plurality of recipients of the electronic communication. The hidden recipient detects whether the request to respond is addressed to at least one recipient other than a sender of the electronic communication. If the request to respond is addressed to at least one recipient other than a sender of the electronic communication, then the hidden recipient manager warns the hidden recipient that the request to respond is addressed to at least one recipient who is unaware of the recipient of the electronic communication by the hidden recipient.

Abstract: A last router in the route of a packet determines when a packet is at the last hop prior to reaching its destination, based on information conveyed in the routing table that the destination is a directly-connected host, and can then convey that information to the host by setting the TTL to zero in the packet being forwarded to its final destination. The host, being so informed that the packet is destined for its IP address, can thereby eliminate the IP address table search for the destination IP address of the incoming packet against the list of its allocated IP addresses to determine if the packet is destined for that host, thereby providing significant performance enhancements to the network system by enabling a receiving host to skip the IP address lookup process and immediately consume the received packet.