Hot Spot Analyzer
for MIPS Technologies MIPS32™ Cores

The Hot Spot Analyzer, or HSA, is an Eclipse plug-in that provides non-intrusive profiling of software running on MIPS32 cores. It is built on the unique Zero Overhead Program Counter (PC) Sampling feature that is included in the MIPS 24K®, 34K™ and 74K™ cores. The tool combines that feature with the System Navigator™ EJTAG probe, and host software to collect and display measurement results in the MIPS Navigator IDE™, an Eclipse-based development and analysis tool suite. HSA is licensed as an Eclipse plug-in option.

Linux Kernel Profiling

HSA was designed specifically to support Linux kernel profiling, which resides in the kseg0 region of the MIPS memory architecture. It can handle large numbers of module and function symbols - the typical Linux kernel has over 12,000 – and accumulate counts for each address range they represent. The HSA accumulates the total counts then sorts and displays percentage of total counts for each symbol providing a profile view of the target’s kernel activity. With this information the user can quickly identify program bottlenecks that are restricting system performance and understand the best methods for making kernel system calls.

Linux Loadable Modules Profiling

Most device drivers are built as Linux loadable modules. These are run-time loaded into the kseg2 memory space of the MIPS architecture. The Hot Spot Analyzer can load multiple .elf symbol files – one for each loadable module - and provide the means of entering the offset address of where the module was loaded. This adjusts each symbol to its absolute virtual address.

Easy to Set Up and Run

The HSA is an Eclipse plug-in that provides its own views and run controls. Because no instrumentation is necessary, it is simple to take measurements on a target MIPS core – plug in the SysNav EJTAG probe, load symbols, launch a debug session, then start the HSA plug-in. The results can be periodically updated or manually with a refresh button to review the latest results.