Garnet Daemon

Garnet Daemon

garnet.py now has a --daemon option, designed to improve turnaround time for garnet dense apps.

Testing a dense app test requires three phases: mapping, pnr, and testing. The pnr phase uses an internal python representation of the garnet circuit. Previously, this circuit object would be rebuilt from scratch for every test, even though it is generally the same structure each time.

The garnet circuit object is such that it cannot be "pickled" (saved to an external file) for later reuse. So, we added the option to launch garnet.py as a reusable background daemon, allowing successive pnr/test invocations to reuse the same circuit over and over.

Using the Daemon

For aha regressions, you can use the aha regress --daemon auto option to tell pnr to use the daemon (or launch one if it does not yet exist).

When doing standalone pnr, you can do the same thing with aha pnr --daemon auto. The pnr program will in turn pass along the --daemon auto switch when it invokes garnet.py.

When using the --daemon switch, it is important to run your job in the background, as the daemon is designed to remain running and available for future jobs (see example below). To control the running daemon, use the various --daemon switches available via garnet.py e.g.

    aha garnet --daemon help
    aha garnet --daemon kill

See "options" section below and/or aha garnet --daemon help for more information about daemon options.

EXAMPLE: Regression suite using daemon

  # Note: examples assume you are running from inside an aha docker instance
  $ source /aha/bin/activate
  $ aha regress pr --daemon auto

EXAMPLE: Using the daemon across multiple pnr sessions

  # Launch the daemon. Background it so that it will persist.
  $ aha pnr apps/pointwise --width 4 --height 2 --daemon auto &

  # Wait for pnr job to complete (optional; can instead just watch for daemon to finish)
  $ aha garnet --daemon wait

  # Subsequent pnr jobs use existing daemon
  $ aha pnr tests/ushift --width 4 --height 2 --daemon auto
  $ aha pnr <app3>       --width 4 --height 2 --daemon auto
  $ aha pnr <app4>       --width 4 --height 2 --daemon auto
  $ ...

EXAMPLE: App development using daemon

( Also see daemon-test.sh )

  $ source /aha/bin/activate

  ### Garnet Verilog build
  $ flags1="--width  4 --height  2 --verilog --use_sim_sram --rv --sparse-cgra --sparse-cgra-combined"
  $ aha garnet $flags1

  ### Kill existing daemon if one exists
  $ aha garnet --daemon kill

  ### Run first app (pointwise) and launch daemon
  ### Remember to background the daemon so that it will persist
  $ app=apps/pointwise
  $ (cd aha/Halide-to-Hardware/apps/hardware_benchmarks/$app; make clean)
  $ aha map $app --chain
  $ aha pnr $app --width 4 --height 2 --daemon auto &
  $ python garnet/garnet.py --daemon wait   # (optional)

  ### Run a second app (ushift) using the daemon
  ### No need to background pnr here, it uses existing background daemon
  $ app=tests/ushift
  $ (cd aha/Halide-to-Hardware/apps/hardware_benchmarks/$app; make clean)
  $ aha map $app --chain
  $ aha pnr $app --width 4 --height 2 --daemon auto

Garnet daemon options

Use --daemon help to find the latest info about how to use the daemon.

$ aha garnet --daemon help

    DESCRIPTION:
      garnet.py can run as a daemon to save you time when generating
      bitstreams for multiple apps using the same garnet circuit. Use
      the "launch" command to build a circuit and keep state in the
      background. The "use-daemon" command reuses the background state
      to more quickly do pnr and bitstream generation.

          --daemon launch -> process args and launch a daemon
          --daemon use    -> use existing daemon to process args
          --daemon auto   -> "launch" if no daemon yet, else "use"
          --daemon wait   -> wait for daemon to finish processing args
          --daemon kill   -> kill the daemon
          --daemon status -> print daemon status and exit
          --daemon force  -> same as kill + launch

    EXAMPLE:
        garnet.py --daemon kill
        garnet.py --width 28 --height 16 --verilog ...
        garnet.py <app1-pnr-args> --daemon launch
        garnet.py <app2-pnr-args> --daemon use
        garnet.py <app3-pnr-args> --daemon use
        garnet.py <app4-pnr-args> --daemon use
        ...
        garnet.py --daemon kill

    NOTE! 'daemon.use' width and height must match 'daemon.launch'!!!
    NOTE 2: cannot use the same daemon for verilog *and* pnr (not sure why).

Also See

For more details see Garnet daemon README