Abstract: A method for dynamically changing system recovery actions based on system load. The method includes measuring a value of a workload characteristic of a computer system over a period of time, detecting an error in the computer system, determining a workload level of the computer system, and selecting a set of error recovery actions in response to the system workload analysis module determining the workload level of the computer system. A workload characteristic defines a type of work performed by the computer system. A workload level can be based on user defined parameters or a measurement of the value of one or more workload characteristics.

Abstract: In accordance with one aspect of the present description, a node of the distributed computing system has multiple communication paths to a data processing resource lock which controls access to shared resources, for example. In this manner, at least one redundant communication path is provided between a node and a data processing resource lock to facilitate reliable transmission of data processing resource lock signals between the node and the data processing resource lock. Other features and aspects may be realized, depending upon the particular application.

Abstract: Extent migration is provided in a data storage environment configured for synchronous replication between a primary and secondary pair of storage entities, each having tiered storage devices. In one embodiment, by way of example only, a migration instruction is sent, by the primary storage entity, to the secondary storage entity, the migration instruction including a relative priority based on a primary ordered heat map of the tiered storage devices of the primary storage entity. The relative priority is used against a secondary ordered heat map of the tiered storage devices of the secondary storage entity to perform the extent migration, regardless of whether the primary and secondary storage entities are identical.

Abstract: Provided are a computer program product, system, and method for determining an availability score based on available resources of different resource types in a storage system to determine whether to perform a failure operation for the storage system. Information is maintained indicating availability of a plurality of storage system resources for a plurality of resource types. An availability score is calculated as a function of a number of available resources of the resource types. Information on the availability score is transmitted to a failure manager. The failure manager uses the transmitted availability information to determine whether to initiate a storage system failure mode for the storage system.

Abstract: Provided are a computer program product, system, and method for a computer program product, system, and method for determining an availability score based on available resources of different resource types in a distributed computing environment of storage servers to determine whether to perform a failure operation for one of the storage servers. A health status monitor program deployed in the storage servers performs: maintaining information indicating availability of a plurality of storage server resources for a plurality of resource types; calculating an availability score as a function of a number of available resources of the resource types; and transmitting information on the availability score to a management program. The management program uses the transmitted information to determine whether to migrate services from the storage server from which the availability score is received to at least one of the other storage servers in the distributed computing environment.

Abstract: Provided are a method, a system, and a computer program product in which a storage controller determines one or more resources that are impacted by an error. A cleanup of tasks associated with the one or more resources that are impacted by the error is performed, to recover from the error, wherein host input/output (I/O) operations continue to be processed, and wherein tasks associated with other resources continue to execute.

Abstract: In accordance with one aspect of the present description, a node of the distributed computing system has multiple communication paths to a data processing resource lock which controls access to shared resources, for example. In this manner, at least one redundant communication path is provided between a node and a data processing resource lock to facilitate reliable transmission of data processing resource lock signals between the node and the data processing resource lock. Other features and aspects may be realized, depending upon the particular application.

Abstract: In accordance with one aspect of the present description, a node of the distributed computing system has multiple communication paths to a data processing resource lock which controls access to shared resources, for example. In this manner, at least one redundant communication path is provided between a node and a data processing resource lock to facilitate reliable transmission of data processing resource lock signals between the node and the data processing resource lock. Other features and aspects may be realized, depending upon the particular application.

Abstract: Provided are a computer program product, system, and method for generating data structure to maintain error and connection information on components and use the data structure to determine an error correction operation. For each of a plurality of first level components in enclosures connected to second level components, errors at the first level component and a connection between the first level component to one of the second level components are determined and error variables are set to indicate whether an error was reported at the first level component. A data structure is generated indicating connections among the first level components and the second level components. The error variable values and the data structure are used to determine an error correction operation with respect to at least one of the first level component and the connected second level component.

Abstract: In accordance with one aspect of the present description, an indication that a communication failure reported in a predetermined time interval is more likely the result of a software failure than a hardware failure may be made if the number of communication links reporting a communication failure in the predetermined time interval exceeds a communication link failure threshold, and the number of communication link devices such as nodes or communication paths which have been implicated as causing a communication failure, exceeds an implicated device threshold. Other features and aspects may be realized, depending upon the particular application.

Abstract: Dynamically adjust an error threshold in a data system based system status changes caused by either an external environment and/or an internal status.

Abstract: Provided are a computer program product, system, and method for processing main cause errors and sympathetic errors in devices in a system. Error data for the devices in the system are analyzed to determine a main cause error for one of the devices that cause at least one sympathetic error in the system. A main cause event object for the determined main cause error and at least one sympathetic event object for the determined at least one sympathetic error resulting from the main cause error are generated. A determination is made from the at least one sympathetic event object of at least one sympathetic event action to perform. The determined at least one sympathetic event action is performed to recover from the at least one sympathetic error represented by the at least one sympathetic event object providing the at least one sympathetic event action.

Abstract: A method according to one embodiment includes determining to move an extent from a source-tier in a storage system to a destination-tier in the storage system, wherein a set of tracks of the extent is presently being accessed. In response to determining that a parameter of the extent exceeds a migration threshold, a destination-tier cache is populated with tracks as they are removed from a read-stack associated with the source-tier and/or a write-stack associated with the source-tier using a predetermined read-to-write ratio. The extent is migrated from the source-tier to the destination-tier.

Abstract: Provided are a computer program product, system, and method for processing main cause errors and sympathetic errors in devices in a system. Error data for the devices in the system are analyzed to determine a main cause error for one of the devices that cause at least one sympathetic error in the system. A main cause event object for the determined main cause error and at least one sympathetic event object for the determined at least one sympathetic error resulting from the main cause error are generated. A determination is made from the at least one sympathetic event object of at least one sympathetic event action to perform. The determined at least one sympathetic event action is performed to recover from the at least one sympathetic error represented by the at least one sympathetic event object providing the at least one sympathetic event action.

Abstract: Provided are a computer program product, system, and method for processing main cause errors and sympathetic errors in devices in a system. Error data for the devices in the system are analyzed to determine a main cause error for one of the devices that cause at least one sympathetic error in the system. A main cause event object for the determined main cause error and at least one sympathetic event object for the determined at least one sympathetic error resulting from the main cause error are generated. A determination is made from the at least one sympathetic event object of at least one sympathetic event action to perform. The determined at least one sympathetic event action is performed to recover from the at least one sympathetic error represented by the at least one sympathetic event object providing the at least one sympathetic event action.

Abstract: A method according to one embodiment includes determining to move an extent from a source-tier in a storage system to a destination-tier in the storage system; determining whether any track from the set of tracks is presently being written to; designating to a write-stack associated with the source-tier each track that is presently being written to and designating to a read-stack associated with the source-tier remaining tracks from the set of tracks; removing oldest tracks from the read-stack and the write-stack until the read-stack and the write-stack have been depleted of tracks; when a parameter of the extent exceeds a migration threshold: populating a destination-tier cache with the tracks as they are removed from the read-stack and the write-stack using a predetermined read-to-write ratio and removing tracks from a source-tier cache that were removed from the read-stack and the write-stack; and migrating the extent from the source-tier to the destination-tier.

Abstract: Extent migration is provided in a data storage environment configured for synchronous replication between a primary and secondary pair of storage entities, each having tiered storage devices. In one embodiment, by way of example only, a migration instruction is sent, by the primary storage entity, to the secondary storage entity, the migration instruction including a relative priority based on a primary ordered heat map of the tiered storage devices of the primary storage entity. The relative priority is used against a secondary ordered heat map of the tiered storage devices of the secondary storage entity to perform the extent migration, regardless of whether the primary and secondary storage entities are identical.

Abstract: Power line disturbance hold up times are dynamically adjusted prior to the commencement of the power disturbance failover based on battery capacity of batteries in racks of the storage system as the batteries either fail, are repaired, or are added to the storage system having at least one uninterruptible power supply (UPS).

Abstract: Exemplary method, system, and computer program embodiments for, in a data storage environment configured for synchronous replication between a primary and secondary pair of storage entities, each having tiered storage devices, extent migration are provided. In one embodiment, by way of example only, a migration instruction is sent, by the primary storage entity, to the secondary storage entity, the migration instruction including a relative priority based on a primary ordered heat map of the tiered storage devices of the primary storage entity. The relative priority is used against a secondary ordered heat map of the tiered storage devices of the secondary storage entity to perform the extent migration, regardless of whether the primary and secondary storage entities are identical.

Abstract: Provided are a computer program product, system, and method for embedding and executing trace functions in code to gather trace data. A plurality of trace functions are embedded in the code. For each embedded trace function, a trace level is included indicating code to which the trace applies. The trace level comprises one of a plurality of levels. During the execution of the code, the embedded trace functions having one of the levels associated with a specified at least one level specified are executed. The embedded trace functions associated with at least one level not comprising one of the at least one specified level are not invoked.