Subject: [PATCH 0/1] Hardware Latency Detector (formerly SMI detector)
Date: Thursday 11th June 2009 04:58:29 UTC (over 7 years ago)
Hi folks, Please find attached my second re-write of the SMI detector, now called the Hardware Latency Detector. This is a loadable module that grabs the CPU for configurable periods of time (all under stop_machine()) and samples the TSC looking for discontinuity. If observed latencies exceed a threshold (for example caused by an System Management Interrupt or similar) then the event is recorded in a global ring_buffer, readable via debugfs. The previous version was too x86-centric, since there is no reason one could not also use this newly renamed hwlat_detector on any supported platform with some kind of underlying firmware/virtualization issues effecting observable system latency measurements. Thanks to akpm and others for feedback comments so far. Changes since the previous version: - Renamed to hwlat_detector - Followed Andrew's cleanup advice - Rewritten the documentation Jon.