439 results about "Call stack" patented technology

A process and system for profiling code executing on a data processing system is provided. Event-based trace data is recorded in response to selected events, and the event-based trace data includes an indication which code is being interrupted. The trace data may be processed to identify a thread or method that was executing during the event. A periodically occurring event is also detected, and a call stack associated with the profiled code is identified in response to detection of the periodically occurring event, such as a timer interrupt. The call stack is examined to identify each routine that is currently executing during the periodically occurring event, and the trace data is recorded with the call stack information. The trace data from the recorded events and the trace data from the call stacks are processed to generate a tree structure in which the nodes indicate the call structure of the routine information from both the trace events and the call stacks.

Data about a transaction is accessed. The transaction has a set of components. A graphical representation of the components of the transaction is displayed such that the graphical representation includes a time axis and a call stack position axis. In one embodiment, the time axis depicts time left to right and the call stack position axis depicts call stack position top to bottom. Additionally, the user interface can receive a selection of one of the components, access data for the selected component and display additional details about that selected component.

Call stack inspection for a thread of execution, including, for each stack frame in the call stack, beginning with the stack frame at the top of the call stack: inspecting the stack frame; determining whether the stack frame was present in the call stack on a previous inspection of the call stack; if the stack frame was not present on a previous inspection, indicating in the stack frame the stack frame's presence on the current inspection of the call stack; and if the stack frame was present on a previous inspection, notifying a user.

A method, apparatus, and computer instructions for determining computer flows autonomically using hardware assisted thread stack and cataloged symbolic data. When a new thread is spawned during execution of a computer program, new thread work area is allocated by the operating system in memory for storage of call stack information for the new thread. Hardware registers are set with values corresponding to the new thread work area. Upon context switch, values of the registers are saved in a context save area for future restoration. When call stack data is post-processed, the operating system or a device driver copies call stack data from the thread work areas to a consolidated buffer and each thread is mapped to a process. Symbolic data may be obtained based on the process identifier and address of the method/routine that was called/returned in the thread. Corresponding program flow is determined using retrieved symbolic data and call stack data.

A batching module that inspects call stacks within a stack evaluator to identify current expressions that can be evaluated in batch with other expressions. If such expressions are identified, the corresponding stacks are blocked from further processing and a batch processing request for processing the expressions is transmitted to the application server. The application server processes the expressions in batch and generates a value for each of the expressions. The blocked stacks are then populated with the values for the expressions.

A batching module that inspects call stacks within a stack evaluator to identify current expressions that can be evaluated in batch with other expressions. If such expressions are identified, the corresponding stacks are blocked from further processing and a batch processing request for processing the expressions is transmitted to the application server. The application server processes the expressions in batch and generates a value for each of the expressions. The blocked stacks are then populated with the values for the expressions.

A method is provided for diagnosing failures in an object-oriented software system. The method comprises collecting runtime diagnostic information; maintaining a record of the diagnostic information in a storage buffer; and dynamically updating the record of the diagnostic information to include a group of the diagnostic information collected over a most recent occurrence of a predetermined interval. The diagnostic information includes at least one set of call stack information for at least one currently running application and at least one set of other information. Each of the at least one set of other information is selected from a set of memory access information, a set of data access information, and a set of paging information for each currently executing process.

The invention finds matches in ordered sequences, e.g. program function call stacks from anomalous software program executions for discovering related or identical software flaws and possible known solutions. Call stacks are matched after removing recursive and uninformative subpatterns, e.g. names of common error handling routines, to see if they were generated due to the same possibly known problem. Sequences statistically unlikely to be matches are pruned from the search. Matches found earlier in the sequences may be weighted differently, e.g. to be more important in call stacks, than other matches. Sequences are indexed so that those relevant to a query are identified automatically without detailed exhaustive search. Maximum matches are found by optimizing a cost function based on weighted sequence similarity.

An evidence-based policy manager generates a permission grant set for a code assembly received from a resource location. The policy manager executes in a computer system (e.g., a Web client or server) in combination with the verification module and class loader of the run-time environment. The permission grant set generated for a code assembly is applied in the run-time call stack to help the system determine whether a given system operation by the code assembly is authorized. Both code assemblies and evidence may be received from a local origin or from a remote resource location via a network (e.g., the Internet). Evidence having different levels of trust may be evaluated in combination so that a permission grant set is associated only with trusted code assemblies. The policy manager may comprise execution modules for parsing a security policy specification, generating one or more code hierarchies, evaluating membership of the received code assembly in one or more code groups, and generating a permission grant set based upon this membership evaluation.

A computer implemented method, apparatus, and computer usable program code for sampling call stack information. Monitoring for an event is performed during an execution of a plurality of threads by a set of processors. A portion of the plurality of threads is identified based on a policy to form a set of identified threads in response to an occurrence of the event. Call stack information is collected for the set of identified threads using an under utilized processor in a set of processors in response to identifying the portion of the plurality of threads, wherein the call stack information is used to profile a processor in the set of processors.

An apparatus and method are provided for the dynamic instrumentation of code to minimize system perturbation during tracing of the execution of the code. With the apparatus and method, “hot spots” in the execution of the code are dynamically determined during tracing of the execution of the code. These “hot spots” are dynamically instrumented, i.e. an event hook is inserted, to cause control to be passed to a handler that determines a caller of the “hot spot” method. The method that called the “hot spot” method, or “caller” method, is identified from a call stack and is dynamically instrumented for an appropriate metric so that the next time the calling method is executed, the dynamically inserted hooks are executed. The execution of the hooks in the caller method is continued for a predetermined period, e.g., number of invocations, to get an understanding of the caller method's characteristics. A list of callers of instrumented methods is maintained and used to determine one or more calling methods of the instrumented caller method. One or more of these calling methods may be instrumented and the hooks inserted in the instrumented caller method (called by the one or more calling methods), are removed. In this way, the call graph of the hot spots of a program execution is “walked up” and characterized over time.

Methods, systems, and computer program products for summarizing operational behavior of a computer program are disclosed. A method for summarizing the operational behavior of a computer program may include executing a computer program in a mode that allows control over execution of the computer program. Execution of the program is paused at predetermined locations corresponding to each instruction in the computer program. For each location, contents of a call stack containing function calls made by the program that have not yet returned are recorded. For each function call in the call stack, information regarding conditions under which the function was called are recorded. Execution of the program is resumed until the next pause location is encountered.

A method and apparatus for monitoring the performance of a computer system with one or more active programs. A periodic sampling of the call stack is obtained. The sampled call stack is examined to infer the system performance similar to that obtained using prior art event based profiling. Embodiments also are directed to a combination approach to describing the system performance using a historical sampling to infer additional detail to fill in the gaps of the sampled data.

A computer implemented method, apparatus, and computer usable program code for sampling call stack information. A flag associated with a target thread is set in a memory work area associated with a virtual machine in response to an interrupt. Monitoring for an event during execution of a plurality of threads created by the virtual machine. A determination is made as to whether the flag is set in response to an occurrence of the event. If the flag is set, the virtual machine makes a call out to a profiler which initiates sampling of the call stack information in response to the flag being set.

A method and apparatus for providing an autonomic mechanism for tracking thread stacks during a trace of a computer program. The method and apparatus include hardware assistance mechanisms that allow the processor to autonomically maintain a work area for each thread where a call stack is stored. With the apparatus and method, the operating system of the computing device informs the operating system of the size of the data area to allocate to a particular thread work area. In addition, when a trace of a computer program is to be performed, the trace software, via the operating system, informs the processor to begin maintaining the thread call stack information in the thread work area. For each thread in the computer program execution, the processor maintains a work area having a size that is determined based on the size communicated by the operating system. The work area is designated by address and length information stored in control registers of the processor. The processor contains microcode that is used to cause the processor to automatically store thread tracking information in the work areas designated by the control registers of the processor when the control bit is set.

A security policy manager generates a permission grant set for a code assembly received from a resource location. The policy manager can execute in a computer system (e.g., a Web client) in combination with the verification module and class loader of the run-time environment. The permission grant set generated for a code assembly is applied in the run-time call stack to help the system determine whether a given system operation by the code assembly is authorized. A permission request set may also be received in association with the code assembly. The permission request set may include a minimum request set, specifying permissions required by the code assembly to run properly. The permission request set may also include an optional request set, specifying permissions requested by the code assembly to provide an alternative level of functionality. In addition, the permission request set may include a refuse request set, specifying permissions that are not to be granted to the code assembly. The permission requests are used to filter a permission set to generate a permission grant set.

A method of diagnosing a fault condition within software can include, responsive to a fault condition within a computing system belonging to an organization, automatically sending call-stack information for the fault condition to a first server within the organization. Within the first server, the call-stack information for the fault condition can be compared with call-stack information from prior fault conditions that occurred within the organization to determine whether the call-stack information for the fault condition matches call-stack information from one of the prior fault conditions. The method further can include sending the call-stack information to a second server for comparison with call-stack information from prior fault conditions that occurred within at least one different organization if the call-stack information for the fault condition does not match.

The present invention provides a method and system for capturing the call stack of a currently-running thread at the time a profiler interrupt occurs. The thread context of the thread is determined before a full push of the thread context is performed by the CPU architecture. The hardware state at the time of the interrupt is used to aid in determining which portions of memory to search for portions of the thread context. Based on the hardware state and the software state of the thread at the time of the interrupt the thread context is captured. Code may also be injected into a thread to capture a thread's call stack. The state of the thread is altered to induce the thread to invoke the kernel's call stack API itself, using its own context.

In embodiments of the invention, selected aspects of a process' call stacks are hashed, and the hash is used to capture the execution state of the process in a concise form and with minimal impact on the performance of the process and with no modification to the process code. The hash allows vendors and developers to classify failures in order to associate them with their known root causes to support rapid customer feedback and to maximize efficiency of correction. Further, the hash provides a metric usable to prioritize diagnosis of failures. In an embodiment of the invention, the identities of modules on the call stack are hashed in combination with some but not all offset information to minimize the affect of patches and minor changes to the code, and improve the ability to discriminate different execution paths.

An evidence-based policy manager generates a permission grant set for a code assembly received from a resource location. The policy manager executes in a computer system (e.g., a Web client or server) in combination with the verification module and class loader of the run-time environment. The permission grant set generated for a code assembly is applied in the run-time call stack to help the system determine whether a given system operation by the code assembly is authorized. Both code assemblies and evidence may be received from a local origin or from a remote resource location via a network (e.g., the Internet). The policy manager may comprise execution modules for parsing a security policy specification, generating a one or more code hierarchies, evaluating membership of the received code assembly in one or more code groups, and generating a permission grant set based upon this membership evaluation.

A method of acquiring software profile information of a target software application includes receiving a programmed interrupt while executing an application in a computer system, servicing the interrupt such that call stack information is acquired and processing the call stack information to produce statistical information concerning function calls. The call stack information includes program counter and other information which is derived from the target application as well as operating system. Some or all of the call stack information may be recorded. The statistical information includes statistics concerning the number of samples wherein a series of functions calls are included in the call stack information and the number of samples wherein a set of function calls are at the top of the call stack information.

A computer program is traced by associating a trigger with at least one code location, and upon encountering the trigger during execution, selectively enabling trace data collection data at subsequent traceable events. Preferably, collection of trace data is enabled only for procedure instances active (i.e., currently executing or on the call stack) at the time that the trigger is encountered. Preferably, a special environmental flag is set on encountering the trigger, saved in each current stack frame, reset on calling any new procedure, and restored from the stack on return from a procedure. Collection of trace data on a traceable event (such as an explicit trace statement in the code) is conditioned on the state of the special environmental flag.

A method for controlling access to deprecated methods of an implementation is provided. The method includes receiving a request to access a method that has been marked as deprecated and building a call stack for the request. Also included is inspecting the call stack to determine if the request is from an application outside of the implementation. The method further includes acting on the request in accordance with a control policy defined by a pluggable policy.