Measuring HAL-Level Timer Latencies

KSRTM is a driver and a Win32 utility that measures HAL-level timer latency. Short code paths make it less sensitive to cache jitter than Srtm. It can determine which Windows OS component or device driver is causing the greatest latency event for a real-time application.

KSRTM measures timer response latencies and obtains reports and histograms of the results.

This tool exercises the real-time HAL extension, and measures and reports timer response latencies against a synchronized clock. It can present a histogram of such latencies and report which kernel component was running when the longest latency event occurred. It can also provide a list of drivers.

KSRTM optionally measures the latencies associated with kernel (DPC-level) and multimedia (user-level) timers. It also allows the timer to drive the sound speaker (a 500-microsecond timer will generate a 1000 Hz square wave). Any timing jitter will produce an audible frequency wobble.

NOTE: KSRTM works only with uniprocessor systems. It is not supported on multiprocessor systems because RTSS is allocated to a separate processor. Instead, SRTM is recommended for measuring latencies on a multiprocessor system.