Summary

EventLog framework exists in the GHC RTS to support profiling of GHC run-time events, such as capability states. A visualizer is currently under development for viewing the profiling information.

Design

• EventLog framework is located in ghc/rts/eventlog/
• Library to parse EventLog files for any visualizer, which relies upon the Data.Binary library: GHC/RTS/Events
• Visualizer: under development

Feature List

• EventLog framework
  • Support for more events, such as cpu and memory usage (TODO)
• EventLog parser library
  • Parsing all events supported by EventLog framework (TODO)
• Visualizer
  • Capability to Thread view (TODO)
  • Filtering of capabilities and/or threads (TODO)
  • Querying: find sequences of events, use regular expressions to find events (TODO)
  • Overlay multiple graphs to display multiple event types (e.g., a graph with thread states, cpu usage, and memory usage)
  • Gracefully handle when a non-EventLog file is loaded by the visualizer (TODO: robustness needed)
  • Export graphs in multiple formats: pdf, jpg, grayscale, etc. (TODO)
  • Link code to events (TODO: very difficult, may not happen)

Code repository

• Available in GHC 6.10.x in ghc_root/rts/eventlog
•  ghc-events: EventLog binary file parser for profilers
•  ThreadScope: thread-level profiler for GHC EventLog events

Contributors

• Satnam Singh
• Simon Marlow
• Donnie Jones <donnie@…>