dspk.runtime

Compute runtime choice.

Every call that runs on a device uses, in order: its runtime= argument, the runtime chosen with set, the DSPK_RUNTIME environment variable, the first compiled-in runtime (GPUs first).

autotune	Tunes the operations on this machine’s devices ahead of time, and compiles their kernels.
available	Names of the runtimes compiled into this build, in preference order (GPUs first).
current	The runtime calls use when they are not given runtime=.
set	Chooses the runtime of every later call that is not given runtime=.

Functions

autotune

autotune(
    runtime: str | None = None,
    channels: Sequence[int] = [32, 64, 128, 384],
    samples: Sequence[int] = [8192, 32768, 131072, 524288],
) -> dict[str, dict[str, float]]

Tunes the operations on this machine’s devices ahead of time, and compiles their kernels.

An operation benchmarks its kernels the first time it meets a device and problem size, which can stall a first run. This does that work now, over a grid of common sizes, and saves the results for every later process. A size off the grid still tunes when it is first met.

Parameters

• runtime : str, default None
  One runtime to tune; by default every runtime compiled in that can open a device here.
• channels : list of int, default [32, 64, 128, 384]
  Channel counts to tune.
• samples : list of int, default [8192, 32768, 131072, 524288]
  Samples per channel to tune.

Returns

• dict — Per runtime tuned, {"sizes": int, "seconds": float}.

Raises

• ValueError: When runtime is not one of this build’s runtimes.

Examples

>>> import dspk
>>> dspk.runtime.autotune(channels=[4], samples=[512], runtime="cpu")

available

available() -> list[str]

Names of the runtimes compiled into this build, in preference order (GPUs first).

Returns

• list of str — Runtime names, such as ["cuda", "wgpu", "cpu"].

Examples

>>> import dspk
>>> names = dspk.runtime.available()

current

current() -> str

The runtime calls use when they are not given runtime=.

The one chosen with set, else the DSPK_RUNTIME environment variable, else the first of available().

Returns

• str — A runtime name.

Raises

• ValueError: When DSPK_RUNTIME names a runtime that is unknown or not compiled in.

set

set(name: str | None) -> None

Chooses the runtime of every later call that is not given runtime=.

Parameters

• name : str or None
  A runtime from available() ("cuda", "hip", "wgpu", "cpu"), or None to go back to the default (DSPK_RUNTIME, else the first available).

Raises

• ValueError: When name is unknown or not compiled into this build.

Examples

>>> import dspk
>>> dspk.runtime.set("cpu")
>>> dspk.runtime.current()
'cpu'
>>> dspk.runtime.set(None)