Source code for pacman.model.resources.variable_sdram

# Copyright (c) 2017-2019 The University of Manchester
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

from spinn_utilities.overrides import overrides
from pacman.exceptions import PacmanConfigurationException
from .abstract_sdram import AbstractSDRAM


class VariableSDRAM(AbstractSDRAM):
    """ Represents an amount of SDRAM used on a chip in the machine.

    This is where the usage increase as the run time increases
    """

    __slots__ = [
        # The amount of SDRAM in bytes used no matter what
        "_fixed_sdram"
        # The amount of extra SDRAm used for each timestep
        "_per_timestep_sdram"
    ]

    def __init__(self, fixed_sdram, per_timestep_sdram):
        """
        :param fixed_sdram:
            The amount of SDRAM (in bytes) that represents static overhead
        :type dtcm: int or numpy.integer
        :param per_timestep_sdram:
            The amount of SDRAM (in bytes) required per timestep.
            Often represents the space to record a timestep.
        :type per_timestep_sdram: float or numpy.float
        """
        self._fixed_sdram = int(fixed_sdram)
        self._per_timestep_sdram = float(per_timestep_sdram)

[docs] @overrides(AbstractSDRAM.get_total_sdram) def get_total_sdram(self, n_timesteps): if n_timesteps is not None: return (self._fixed_sdram + self._per_timestep_sdram * n_timesteps) if self._per_timestep_sdram == 0: return self._fixed_sdram raise PacmanConfigurationException( "Unable to run forever with a variable SDRAM cost")
@property @overrides(AbstractSDRAM.fixed) def fixed(self): return self._fixed_sdram @property @overrides(AbstractSDRAM.per_timestep) def per_timestep(self): return self._per_timestep_sdram def __add__(self, other): return VariableSDRAM( self._fixed_sdram + other.fixed, self._per_timestep_sdram + other.per_timestep) def __sub__(self, other): return VariableSDRAM( self._fixed_sdram - other.fixed, self._per_timestep_sdram - other.per_timestep)
[docs] @overrides(AbstractSDRAM.sub_from) def sub_from(self, other): return VariableSDRAM( other.fixed - self._fixed_sdram, other.per_timestep - self._per_timestep_sdram)
[docs] @overrides(AbstractSDRAM.report) def report(self, timesteps, indent="", preamble="", target=None): print(indent, preamble, "Fixed {} bytes Per_timestep {} bytes for a total of {}".format( self._fixed_sdram, self._per_timestep_sdram, self.get_total_sdram(timesteps)), file=target)