Abstract: A system, method and computer program product for calibrating a Time Of Day (TOD)-clock in a computing system node provided in a multi-node network. The network comprises an infrastructure of computing devices each having a physical clock providing a time base for executing operations that is stepped to a common oscillator. The system implements steps for obtaining samples of timing values of a computing device in the network, the values including a physical clock value maintained at that device and a TOD-offset value; computing an oscillator skew value from the samples; setting a fine steering rate value as equal to the opposite of the computed oscillator skew value; and, utilizing the fine steering rate value to adjust the physical clock value and correct for potential oscillator skew errors occurring in the oscillator crystal at the computing device.

Abstract: A mechanism is provided for multi-part aggregated variables in structured external storage. The shared external storage provides a serialized, aggregated structure update capability. The shared external storage identifies each local value for which a group value is needed by name. Each time a member writes out its value, the member specifies the name of the object, the member's current value, and the type of aggregate function to apply (e.g., minimum, maximum, etc.). The structured external storage in one atomic operation updates the member's value, recalculates the aggregate of all of the individual values, and returns the aggregate to the member. The advantage of this approach is that it requires only one write operation to the structured external storage. The update operation does not require locking, because the operation is atomic.

Abstract: A mechanism for automatic reallocation of shared external storage structures is provided. The shared external storage divides the dynamically allocable storage into fixed sized blocks referred to as allocation units. To create an object of a specific type, the shared external storage uses some number of allocation units. If the object will fit in one allocation unit, then it is placed in one allocation unit. If the object is larger than one allocation unit, then the appropriate number of allocation units is obtained and chained together to contain all of the information of the required object. When an object so allocated is no longer needed, the shared external storage breaks the object down to a set of one or more fixed sized allocation units. The shared external storage then returns the allocation units to the pool of available objects.

Abstract: A coupling facility is coupled to one or more other coupling facilities via one or more peer links. The coupling of the facilities enables various functions to be supported, including the duplexing of structures of the coupling facilities. Duplexing is performed on a structure basis, and thus, a coupling facility may include duplexed structures, as well as non-duplexed or simplexed structures.

Abstract: A coherency manager provides coherent access to shared data by receiving a copy of updated database data from a host computer through RDMA, the copy including updates to a given database data; storing the copy of the updated database data as a valid copy of the given database data in local memory; invalidating local copies of the given database data on other host computers through RDMA; receiving acknowledgements from the other host computers through RDMA that the local copies of the given database data have been invalidated; and sending an acknowledgement of receipt of the copy of the updated database data to the host computer through RDMA. When the coherency manager receives a request for the valid copy of the given database data from a host computer through RDMA, it retrieves the valid copy of the given database data from the local memory and returns the valid copy through RDMA.

Abstract: A coupling facility is coupled to one or more other coupling facilities via one or more peer links. The coupling of the facilities enables various functions to be supported, including the duplexing of structures of the coupling facilities. Duplexing is performed on a structure basis, and thus, a coupling facility may include duplexed structures, as well as non-duplexed or simplexed structures.

Abstract: In a networked data processing system, the updating of timing parameters is carried out via a process in which the detection of the loss of communications with the network is not immediately employed as an indication of parameter invalidity but rather the process employs a system specific delay which permits actions such as server or link recovery to occur without necessitating the declaration of timing parameter invalidity.

Abstract: A timing network is provided that includes a plurality of servers. The servers of the network obtain information used to maintain the servers in time synchronization, thus ensuring the integrity of the servers.

Abstract: Recovery is provided in a timing network. A configuration is defined for that network, and in that configuration, an active primary server is identified that provides a clock source for the network. Additionally, an alternate server is identified that can perform the role of the active primary server, should the active primary server fail. In response to a failure of the primary server, the alternate server detects the failure and performs takeover of the primary server.

Abstract: A timing network is provided that includes a plurality of servers. The servers of the network obtain information used to maintain the servers in time synchronization, thus ensuring the integrity of the servers.

Abstract: A method, system, and product in a data processing system are disclosed for providing centralized management of an INFINIBAND distributed system-area network that includes multiple end nodes. A manager application is established in one of the end nodes. An agent application is established in one or more end nodes. Each agent application is independent from the manager application. The manager application maintains a current list of active agent applications and uses the list to manage the agent applications in the end nodes.

Abstract: A system, method and computer program product for dynamically debugging a multi-node network comprising an infrastructure including a plurality of devices, each device adapted for communicating messages between nodes which may include information for synchronizing a timing clock provided in each node. The apparatus comprises a plurality of probe links interconnecting each node with a probe device that monitors data included in each message communicated by a node. Each probe device processes data from each message to determine existence of a trigger condition at a node and, in response to detecting a trigger condition, generates a specialized message for receipt by all nodes in the network. Each node responds to the specialized message by halting operation at the node and recording data useful for debugging purposes. In this manner, debug information is collected at each node at the time of a first error detection and collected dynamically at execution time without manual intervention.

Abstract: A system, method and computer program product for calibrating a Time Of Day (TOD)-clock in a computing system node provided in a multi-node network. The network comprises an infrastructure of computing devices each having a physical clock providing a time base for executing operations that is stepped to a common oscillator. The system implements steps for obtaining samples of timing values of a computing device in the network, the values including a physical clock value maintained at that device and a TOD-offset value; computing an oscillator skew value from the samples; setting a fine steering rate value as equal to the opposite of the computed oscillator skew value; and, utilizing the fine steering rate value to adjust the physical clock value and correct for potential oscillator skew errors occurring in the oscillator crystal at the computing device.

Abstract: A system, method and computer program product for calibrating a Time Of Day (TOD)-clock in a computing system node provided in a multi-node network. The network comprises an infrastructure of computing devices each having a physical clock providing a time base for executing operations that is stepped to a common oscillator. The system implements steps for obtaining samples of timing values of a computing device in the network, the values including a physical clock value maintained at that device and a TOD-offset value; computing an oscillator skew value from the samples; setting a fine steering rate value as equal to the opposite of the computed oscillator skew value; and, utilizing the fine steering rate value to adjust the physical clock value and correct for potential oscillator skew errors occurring in the oscillator crystal at the computing device.

Abstract: A timing network is provided that includes a plurality of servers. The servers of the network obtain information used to maintain the servers in time synchronization, thus ensuring the integrity of the servers.

Abstract: A timing network is provided that includes a plurality of servers. The servers of the network obtain information used to maintain the servers in time synchronization, thus ensuring the integrity of the servers.

Abstract: Recovery is provided in a timing network. A configuration is defined for that network, and in that configuration, an active primary server is identified that provides a clock source for the network. Additionally, an alternate server is identified that can perform the role of the active primary server, should the active primary server fail. In response to a failure of the primary server, the alternate server detects the failure and performs takeover of the primary server.

Abstract: In a networked data processing system, the updating of timing parameters is carried out via a process in which the detection of the loss of communications with the network is not immediately employed as an indication of parameter invalidity but rather the process employs a system specific delay which permits actions such as server or link recovery to occur without necessitating the declaration of timing parameter invalidity.

Abstract: A coupling facility is coupled to one or more other coupling facilities via one or more peer links. The coupling of the facilities enables various functions to be supported, including the duplexing of structures of the coupling facilities. Duplexing is performed on a structure basis, and thus, a coupling facility may include duplexed structures, as well as non-duplexed or simplexed structures.

Abstract: A method for providing a message-time-ordering facility is disclosed. The method comprises initiating the message-timer ordering facility for a message at a sender system. Initiating includes setting a delay variable to zero. The message is sent to a receiver system in response to initiating the message-time-ordering facility. Sending the message includes marking the message with a first departure time-stamp responsive to a sender system clock and transmitting the message to the receiver system. The message is received at the at the receiver system, receiving includes delaying the processing of the message until the time on a receiver system clock is greater than the first departure time-stamp and recording a time associated with the delaying the processing of the message in the delay variable. A response to the message is sent to the sender system in response to receiving the message.