Abstract: In one embodiment, a method and apparatus for high-efficiency time-series archiving for computer server telemetry signals are disclosed. The method includes maintaining a data structure in a kernel module that identifies information related to a system including the kernel module, the information to be manipulated by the kernel module, comparing, by a kernel in the system that loads the kernel module, the data structure of the kernel module with one or more other data structures of kernel modules the kernel loads, and performing, by the kernel, an error routine if an incompatibility is found between the data structure and the one or more other data structures. Other embodiments are also disclosed.

Abstract: A method for analyzing memory after a system panic to identify scope and cause of memory corruption. The method includes retrieving a memory image for a computer system and identifying a data structure in the memory image that caused the panic. A rule set for the identified data structure is selected and applied to the memory image to determine a scope of the memory corruption. The method includes identifying data structures in the memory that are related to the identified data structure by type, structure, content, or location and applying the rule set to this subset of data structures. The method may include generating the rule set for the identified data structure and then validating the created rule set such as by applying it to data structures that are known to be uncorrupted. The corrupted data structures are then processed to determine a cause of the corruption.

Abstract: A method for determining an ownership of for a multiple owner lock. The method includes determining potential owners of the lock by inspecting a core file of a computer system or memory of a live system to determine which threads have pointers to the lock. The method includes identifying a stack for the threads with a stack pointer pointing to the current active frame and dividing the stack into active and inactive portions. The stack information is examined for each potential owner of the lock for pointers to the lock. If the thread has a pointer to the lock in the inactive portion of the stack, the thread is removed from the set of potential owners. The method includes retrieving a waiting list for the lock, and any threads on the waiting list are removed from the set of potential owners.

Abstract: A method for analyzing memory after a system panic to identify scope and cause of memory corruption. The method includes retrieving a memory image for a computer system and identifying a data structure in the memory image that caused the panic. A rule set for the identified data structure is selected and applied to the memory image to determine a scope of the memory corruption. The method includes identifying data structures in the memory that are related to the identified data structure by type, structure, content, or location and applying the rule set to this subset of data structures. The method may include generating the rule set for the identified data structure and then validating the created rule set such as by applying it to data structures that are known to be uncorrupted. The corrupted data structures are then processed to determine a cause of the corruption.

Abstract: A method for determining code execution paths based on stack information provided in a core file. Stack information is processed to determine flow gaps between pairs of functions identified in frames in the stack. Direct call paths are determined between the functions by determining every direct path between the two functions by scanning the source function for called functions and then repeatedly scanning the called functions until a branch reaches the destination function or terminates with a function other than the destination function. In another embodiment, the paths are determined by identifying call branches from the source function and terminating the following of a call branch whenever a repeat function is found. In another embodiment, the result set of potential paths is generated by identifying branches from the source function but only continuing to follow a branch when intermediate functions are followed by a restore function.

Abstract: A method for determining an ownership of for a multiple owner lock. The method includes determining potential owners of the lock by inspecting a core file of a computer system or memory of a live system to determine which threads have pointers to the lock. The method includes identifying a stack for the threads with a stack pointer pointing to the current active frame and dividing the stack into active and inactive portions. The stack information is examined for each potential owner of the lock for pointers to the lock. If the thread has a pointer to the lock in the inactive portion of the stack, the thread is removed from the set of potential owners. The method includes retrieving a waiting list for the lock, and any threads on the waiting list are removed from the set of potential owners.