Performance profiling with ghc-events-analyze

ghc-events-analyze is a new simple Haskell profiling tool that uses GHC’s eventlog system. It helps with some profiling use cases that are not covered by the existing GHC profiling modes or tools. It has two major features:

• While ThreadScope shows CPU activity across all your cores, ghc-events-analyze shows CPU activity across all your Haskell threads.
• It lets you label periods of time during program execution (by instrumenting your code with special trace calls) and then lets you visualize those time periods or get statistics on them.

Read more at well-typed.com