Source code for pacman.model.resources.multi_region_sdram

# Copyright (c) 2017 The University of Manchester
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import annotations
from enum import Enum
import math
from typing import Any, Dict, Optional, TextIO, Union

import numpy
from typing_extensions import TypeAlias

from spinn_utilities.overrides import overrides

from .abstract_sdram import AbstractSDRAM
from .constant_sdram import ConstantSDRAM
from .variable_sdram import VariableSDRAM

_RegionKey: TypeAlias = Union[int, str, Enum]
_Value: TypeAlias = Union[int, float, numpy.integer, numpy.floating]


def _ceil(value: _Value) -> int:
    return math.ceil(value)


class MultiRegionSDRAM(AbstractSDRAM):
    """
    A resource for SDRAM that comes in regions.

    .. note::
        Adding or subtracting two MultiRegionSDRAM objects will be assumed to
        be an operation over multiple cores/placements so these functions
        return a VariableSDRAM object without the regions data.

        To add extra SDRAM costs for the same core/placement use the methods
        :py:meth:`add_cost` and :py:meth:`merge`.
    """

    __slots__ = (
        # The regions of SDRAM, each of which is an AbstractSDRAM
        "__regions",
        # The total cost of all the regions
        "_total")

    def __init__(self) -> None:
        self.__regions: Dict[_RegionKey, AbstractSDRAM] = {}
        self._total: AbstractSDRAM = ConstantSDRAM(0)

    @property
    def regions(self) -> dict[_RegionKey, AbstractSDRAM]:
        """
        The map from region identifiers to the amount of SDRAM required.

        :rtype: dict(int or str or enum, AbstractSDRAM)
        """
        return self.__regions

[docs] def add_cost(self, region: _RegionKey, fixed_sdram: _Value, per_timestep_sdram: _Value = 0) -> None: """ Adds the cost for the specified region. :param region: Key to identify the region :param fixed_sdram: The fixed cost for this region. :param per_timestep_sdram: The variable cost for this region is any """ if per_timestep_sdram: self.nest(region, VariableSDRAM( _ceil(fixed_sdram), _ceil(per_timestep_sdram))) else: self.nest(region, ConstantSDRAM(_ceil(fixed_sdram)))
[docs] def nest(self, region: _RegionKey, other: AbstractSDRAM) -> None: """ Combines the other SDRAM cost, in a nested fashion. The totals for the new region are added to the total of this one. A new region is created summarising the cost of others. If other contains a regions which is the same as one in self they are *not* combined, but kept separate. :param region: Key to identify the summary region :type region: int or str or enum :param AbstractSDRAM other: Another SDRAM model to make combine by nesting """ self._total += other if region in self.__regions: if isinstance(other, MultiRegionSDRAM): r = self.__regions[region] if isinstance(r, MultiRegionSDRAM): r.merge(other) else: other.nest(region, r) self.__regions[region] = other else: self.__regions[region] += other else: self.__regions[region] = other
[docs] def merge(self, other: MultiRegionSDRAM) -> None: """ Combines the other SDRAM costs keeping the region mappings. .. note:: This method should only be called when combining cost for the same core/ placement. Use + to combine for different cores :param MultiRegionSDRAM other: Another mapping of costs by region """ self._total += other for region in other.regions: if region in self.regions: self.__regions[region] += other.regions[region] else: self.__regions[region] = other.regions[region]
[docs] @overrides(AbstractSDRAM.report) def report(self, timesteps: Optional[int], indent: str = "", preamble: str = "", target: Optional[TextIO] = None) -> None: self._total.report(timesteps, indent, preamble, target) for region in self.__regions: self.__regions[region].report( timesteps, indent+" ", str(region)+":", target)
[docs] def get_total_sdram(self, n_timesteps: Optional[int]) -> int: """ The total SDRAM. :param int n_timesteps: number of timesteps to cost for :return: """ return self._total.get_total_sdram(n_timesteps)
def __eq__(self, other: Any) -> bool: if isinstance(other, MultiRegionSDRAM): return self._total == other._total return self._total == other def __add__(self, other: AbstractSDRAM) -> AbstractSDRAM: """ Combines this SDRAM resource with the other one and creates a new one. :param other: another SDRAM resource :return: a New AbstractSDRAM """ return self._total + other @property def fixed(self) -> int: """ The fixed SDRAM cost. """ return self._total.fixed @property def per_timestep(self) -> float: """ The extra SDRAM cost for each additional timestep. .. warning:: May well be zero. """ return self._total.per_timestep @property @overrides(AbstractSDRAM.short_str) def short_str(self) -> str: return f"Multi:{self._total.short_str}"