Recording the core data of a computer process which provides trace data

Abstract

A method, apparatus and computer program for recording the core data of a computer process, the computer process comprising trace points and core data is provided for each such trace point. A first set of core data comprising an image of a memory for the computer process is stored in response to a first set of trace data being produced for the computer process for a first trace point. A second set of core data is stored in response to a second set of trace data being produced for the computer process for a second trace, where the second set of core data comprises a record of any change in current memory contents for the computer process with respect to the first set of core data.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application claims the benefit of priority to United Kingdom Patent Application Serial No. 1219535.0, filed on Oct. 31, 2012, the contents of which are hereby incorporated by reference.FIELD OF INVENTION[0002]The present invention relates to recording the core data of a computer process wherein the computer process is arranged to provide trace data.BACKGROUND[0003]Computing systems require memory in order to function. This computer memory is referenced by address and the full range of memory available to the system is known as the address space. When a problem with a computer system is being investigated, a copy or image of this address space, that is, the memory addresses and address data contents, can be stored for later inspection. Such data is commonly referred to as core or dump data and stored in a core or dump file.[0004]If the program under investigation has been written to include trace entries, these can be enabled so that ...

AI Technical Summary

Benefits of technology

[0007]Embodiments of the invention remove the need for a full core file to be saved at the point at which a crash or other problem occurs with the process being monitored, thus speeding up the computer processing and reducing storage requirements. Since such core files can be very large and thus time consuming to produce, embodiments of the invention therefore reduce the processing time required to recover from a crash.

[0008]Embodiments of the invention enable the state of memory to be more quickly determined at any given trace point, providing the engineer with both trace data and the contemporaneous memory image, thus improving the information available for identifying the cause of the relevant fault. Therefore, trace data references to memory locations, such as pointers, may be dereferenced so as to provide further insight into the cause of a problem being diagnosed.

[0009]Embodiments of the invention provide a storage and processing-efficient method for recording core data at each trace point that avoids the need to perform repeated memory dumps.

Problems solved by technology

One problem with this arrangement is that tracing has limitations as only those areas of the address space that the developer decided to trace when the code was written are available for subsequent analysis.

For example if a parameter list is traced out containing a pointer, it is not possible to view the storage addressed by the pointer unless it also happened to be specifically traced out.

Another problem is that the core file may not reflect the content of memory when a problem actually occurred.

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