A method in a data processing system for implementing a sampling performance analysis for a selected application within a multi-thread operating system having a high degree of isolation between applications within the operating system, said method comprising the data processing system implemented steps of:
- initiating a trace function for controlling the execution of a selected application and accessing memory within said selected application;
- substituting a mole program for a selected code segment at a particular memory location within said selected application;
- in response to an initial execution of said mold program within said selected application, initiating a separate running thread program within said operating system and rewriting said selected code segment at said particular memory location within said selected application, said separate running thread program continuously generating break point interrupts on a periodic basis;
- in response to each break point interrupt generated by said separate running thread program during execution of said selected application suspending execution of said selected application, examining said selected application utilizing said trace function and storing an indication of a current execution location within said selected application at said suspension for utilization in performance analysis;
- and
- thereafter, resuming execution of said selected application.