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Module Munin

Records of runs and artifacts, in plain files.

munin records what a program does as it runs: its params, its metrics step by step, readings of its machine and devices, files it produces, and versioned artifacts such as checkpoints. Everything lives in a store, a directory of JSON and text files that Store_format specifies, so that jq, tail -f or another program reads a store as well as this library does. No server and no account is involved.

A run is one execution of a program. The program opens a Session, the run's one writer, declares its metrics and logs samples into them, and finishes the session at the end. Readers list runs (Store.runs), each a Run as its first and last records state it, and fold a run's log into its History: series, statistics and best values (Metric). An artifact is a name with immutable versions that a run publishes and other runs use (Artifact). Value and Provenance are what runs record about themselves.

A run of a training loop, then the best loss read back:

ocaml

  let store = Munin.Store.open_ () in
  let id =
    Munin.Session.within
      (Munin.Session.start ~store ~experiment:"mnist" ())
    @@ fun s ->
    let loss = Munin.Session.metric s ~goal:`Minimize "train/loss" in
    for step = 0 to 999 do
      Munin.Session.log loss ~step (train_step ())
    done;
    Munin.Session.id s
  in
  let run = Option.get (Munin.Store.run store id) in
  let h = Munin.History.read run in
  match Munin.History.(goal h "train/loss", stats h "train/loss") with
  | Some g, Some st -> Munin.Metric.best g st
  | _ -> None

#module Store_format : sig ... end

The files of a munin store.

#module Value : sig ... end

Values of params, summaries and metadata.

#module Provenance : sig ... end

How and where a run started.

#module Metric : sig ... end

Samples, series and their statistics.

#module Run : sig ... end

Runs, as a listing reads them.

#module History : sig ... end

What a run's log says, folded.

#module Artifact : sig ... end

Artifact versions.

#module Store : sig ... end

Stores: a root directory and what it holds.

#module Session : sig ... end

Writing a run.