Abstract: Method, system, and computer program product embodiments of a time-based trace facility for facilitating software debugging without interfering with the run-time behavior, performance or resource usage of the traced software are provided. The trace facility resides in a different address space than the target address space and uses different time-slices of CPU resources to execute the instructions in the address spaces. The trace facility uses a cross-memory mode to read the state data from the target address space in accordance with a time schedule. The trace facility writes the state data to a trace area, which may be located in either the target or trace address spaces or external storage. With this approach, the trace facility can read a large amount of state data frequently to construct the type of historical record needed to analysis run-time behavior, performance and resource usage. The trace facility may use a parameter file to configure a particular trace e.g.

Abstract: Computer systems and methods for call-stacks representation for easier analysis of thread dumps. Execution data for a number of process threads are accessed by a parser in a thread dump wherein execution data includes a number of call-stacks. Process threads have corresponding call-stacks comprising information about active program subroutines of the thread. Threads are grouped in a number of sets that include threads with one or more actions in common. The sets correspond to a same action or subroutine in the call-stacks of the grouped threads. A tree representation of the execution data is generated based on the active actions in the call-stacks. In the tree representation, a first set of grouped threads is a child to a second set of grouped threads when the action corresponding to the first set is invoked by the subroutine corresponding to the second set.

Abstract: A system and method for identifying a root cause of a wait in a computer system are provided. Given the identity of a thread of interest and time window, a longest wait period for the thread of interest within the time window is identified. The longest wait period is used as a starting node to generate a ready tree by walking backwards through the data in a system trace to construct a tree of readying events that ready threads for running on a processor. A potentially anomalous chain of events is automatically identified and highlighted in the ready tree. A visualization of the ready tree is presented to a user so that the user can explore the events in the tree and annotate the automatically generated tree to aid in problem diagnosis.

Abstract: In an embodiment, virtual trace records are read and physical trace records are created and displayed. The virtual trace records are associated with virtual processors allocated to logical partitions in a logically-partitioned computer system. Each of the virtual trace records has a wait timestamp, specifying a time at which a virtual processor began waiting to be dispatched and a wait time delta, specifying an amount of time that the virtual processor waited to be dispatched. An execute timestamp is created in each of the virtual trace records, which specifies a time at which the virtual processor was dispatched. The virtual trace records are sorted for each of the virtual processors by the execute timestamp. Physical trace records are created based on the sorted virtual trace records. Each physical trace record describes a dispatch of one of the virtual processors to one of the physical processors.

Abstract: A computer implemented method, apparatus, and computer usable program code for network fault isolation. A plurality of real-time path traces is performed between the sender and the receiver to form a plurality of trace paths in response to receiving a request for the network fault isolation between a sender and a receiver. A determination is made as to whether an asymmetry is present between the sender and the receiver from the plurality of trace paths. A set of routers is identified with each trace path in the plurality of trace paths to form a plurality of identified routers. Each event stored is identified for the plurality of identified routers to form a set of identified events.

Abstract: A data processing apparatus is provided with packing circuitry 130 arranged to receive said source data elements from said trace data receiver and applies a packing protocol to said source data elements to pack data of source data elements of a source trace stream into a packed trace data stream for supply to trace accepting circuitry in a format comprising acceptance data elements. The acceptance data elements have a bit-length that is not a factor of the source data element bit-length. In some arrangements the source data elements are non byte-sized data elements. In alternative arrangements, the packing circuitry packs a first positive integer number of source data elements into a data chunk comprising a second, different positive integer number of acceptance data elements.

Abstract: A tracing mechanism operates at a low level of detail during normal program execution and automatically provides an increased level of detail during exception situations. The tracing mechanism also discloses history information prior to the exception situation. Program activity trace data is used to control action of the configurable trace facility allowing history data of a program's activity to be combined with current trace data into a persistent log. The trace facility may also be configured to recognize specified trigger values from either hardware or software means.

Abstract: This invention provides a system including a computer and a storage-subsystem comprising at least either a first storage area for storing data sent from the computer or a second storage area to be associated with the first storage area, for storing replicated data of data stored in the first storage area. This system includes a replication processing status referral unit for referring to a replication processing status of data of the first storage area and the second storage area to be associated, and an output unit for outputting first performance information concerning data I/O stored in the first storage area, and outputting second performance information concerning data I/O stored in the second storage area together with the first performance information when the replicated data is being subject to replication processing from the first storage area to the second storage area as a result of referring to the replication processing status.

Abstract: Nodes in a query execution data structure have monitor and dump methods defined. The monitor method enables the collection of information from the node. The dump method outputs the monitored information from each node. A monitor and debug mechanism of the preferred embodiments includes a graphical user interface that allows a user to graphically examine a query execution tree, to enable monitoring of the nodes on a node-by-node basis, and to view information dumped from the query execution data structure as the query is executed or after the query is executed. The result is a powerful tool that allows efficiently monitoring and debugging a query implemented in an object oriented query execution data structure.

Abstract: A computer program product and method for displaying trace log entries from a plurality of trace logs call for identifying trace log entries; determining a degree of relevancy for each of the trace log entries; and classifying the trace log entries.