NAME

       Spacetime - Profiling of a program's space behaviour over time.

Module

       Module   Spacetime

Documentation

       Module Spacetime
        : sig end

       Profiling  of  a  program's space behaviour over time.  Currently only supported on x86-64
       platforms running 64-bit code.

       To use the functions in this module you must:

       -configure the compiler with "-spacetime";

       -compile to native code.  Without these conditions being satisfied the functions  in  this
       module will have no effect.

       Instead of manually taking profiling heap snapshots with this module it is possible to use
       an automatic snapshot facility that writes profiling information at fixed intervals  to  a
       file.  To  enable this, all that needs to be done is to build the relevant program using a
       compiler   configured   with   -spacetime;    and    set    the    environment    variable
       OCAML_SPACETIME_INTERVAL  to an integer number of milliseconds giving the interval between
       profiling heap snapshots. This interval should not be made excessively small  relative  to
       the  running  time  of the program. A typical interval to start with might be 1/100 of the
       running time of the program.  The program must exit "normally" (i.e.  by  calling  exit  ,
       with  whatever exit code, rather than being abnormally terminated by a signal) so that the
       snapshot file is correctly completed.

       When using the automatic snapshot mode the profiling output is written to  a  file  called
       "spacetime-<pid>" where <pid> is the process ID of the program.  (If the program forks and
       continues executing then multiple files may be produced with different pid numbers.)   The
       profiling  output  is by default written to the current working directory when the program
       starts.  This may be customised by setting  the  OCAML_SPACETIME_SNAPSHOT_DIR  environment
       variable to the name of the desired directory.

       If  using  automatic  snapshots  the  presence  of  the save_event_for_automatic_snapshots
       function, below, should be noted.

       The functions in this module are thread safe.

       For functions to decode the information  recorded  by  the  profiler,  see  the  Spacetime
       offline library in otherlibs/.

       val enabled : bool

       enabled is true if the compiler is configured with spacetime and false otherwise

       module Series : sig end

       module Snapshot : sig end

       val save_event_for_automatic_snapshots : event_name:string -> unit

       Like  Spacetime.Series.save_event  ,  but  writes  to  the  automatic snapshot file.  This
       function is a no-op if OCAML_SPACETIME_INTERVAL was not set.