x
/
bareon-allocator
Code Issues Proposed changes

Refactoring of allocation solvers. 

Implemented layering so it will allow to have multiple
solver engines.

Implements blueprint: dynamic-allocation

Change-Id: I7ed1ec0216fb9778b4fa5be4fb4f6141a0e26fc9
This commit is contained in:
Evgeniy L 2016-03-30 15:06:51 +03:00
parent 5d6290ac1a
commit b1cef8c4a0
19 changed files with 1137 additions and 409 deletions
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393
bareon_allocator/allocators.py
View File

@ -14,21 +14,13 @@
# License for the specific language governing permissions and limitations
# under the License.
import itertools
import math
import numpy as np
from oslo_log import log
from scipy.optimize import linprog
from bareon_allocator import errors
from bareon_allocator.parsers import DynamicSchemaParser
from bareon_allocator.solvers import LinearProgramCreator
from bareon_allocator.solvers import LinearProgrammingScipySolver
from bareon_allocator import utils
from bareon_allocator.sequences import CrossSumInequalitySequence
LOG = log.getLogger(__name__)
@ -37,388 +29,39 @@ class DynamicAllocator(object):
def __init__(self, hw_info, schema):
LOG.debug('Hardware information: %s', hw_info)
LOG.debug('Spaces schema: %s', schema)
dynamic_schema = DynamicSchemaParser(hw_info, schema)
LOG.debug('Spaces objects: %s', dynamic_schema.spaces)
LOG.debug('Disks objects: \n%s', dynamic_schema.disks)
self.dynamic_schema = DynamicSchemaParser(hw_info, schema)
LOG.debug('Spaces objects: %s', self.dynamic_schema.spaces)
LOG.debug('Disks objects: %s', self.dynamic_schema.disks)
self.solver = DynamicAllocationLinearProgram(
dynamic_schema.disks,
dynamic_schema.spaces)
linear_program = LinearProgramCreator(
self.dynamic_schema).linear_program()
self.solver = LinearProgrammingScipySolver(linear_program)
def generate_static(self):
sizes = self.solver.solve()
return sizes
class DynamicAllocationLinearProgram(object):
"""Linear programming allocator.
Use Linear Programming method [0] (the method itself has nothing to do
with computer-programming) in order to formulate and solve the problem
of spaces allocation on disks, with the best outcome.
In this implementation scipy is being used since it already implements
simplex algorithm to find the best feasible solution.
[0] https://en.wikipedia.org/wiki/Linear_programming
[1] http://docs.scipy.org/doc/scipy-0.16.0/reference/generated
/scipy.optimize.linprog.html
[2] https://en.wikipedia.org/wiki/Simplex_algorithm
"""
weight_set_mapping = [
# Don't use minimal size, in this case
# we will get a weight for the space which
# in combination with space which has max_size
# so there will be unallocated space
# ['min_size', 'best_with_disks'],
# ['max_size', 'best_with_disks'],
['min_size', 'max_size', 'best_with_disks']]
def __init__(self, disks, spaces):
self.disks = disks
self.spaces = spaces
# Coefficients of the linear objective minimization function.
# During iteration over vertexes the function is used to identify
# if current solution (vertex) satisfies the equation more, than
# previous one.
# Example of equation: c[0]*x1 + c[1]*x2
self.objective_function_coefficients = []
# A matrix which, gives the values of the equality constraints at x,
# when multipled by x.
self.equality_constraint_matrix = []
# An array of values representing right side of equation,
# left side is represented by row of `equality_constraint_matrix`
# matrix
self.equality_constraint_vector = np.array([])
self.upper_bound_constraint_matrix = []
self.upper_bound_constraint_vector = []
self.lower_bound_constraint_matrix = []
self.lower_bound_constraint_vector = []
# Specify boundaries of each x in the next format (min, max). Use
# None for one of min or max when there is no bound.
self.bounds = np.array([])
# For each space, xn (size of the space) is represented
# for each disk as separate variable, so for each
# disk we have len(spaces) * len(disks) sizes
self.x_amount = len(self.disks) * len(self.spaces)
# TODO(eli): has to be refactored
# Here we store indexes for bounds and equation
# matrix, in order to be able to change it on
# refresh
self.weight_equation_indexes = []
self._set_spaces_sets_by(self.weight_set_mapping[0])
self._init_equation(self.disks, self.spaces)
self._init_objective_function_coefficient()
self._init_min_max()
self._refresh_weight()
def solve(self):
upper_bound_matrix = self._make_upper_bound_constraint_matrix() or None
upper_bound_vector = self._make_upper_bound_constraint_vector() or None
LOG.debug('Objective function coefficients human-readable:\n%s\n',
utils.format_x_vector(self.objective_function_coefficients,
len(self.spaces)))
LOG.debug('Equality equation:\n%s\n',
utils.format_equation(
self.equality_constraint_matrix,
self.equality_constraint_vector,
len(self.spaces)))
LOG.debug('Inequality equation:\n%s\n',
utils.format_equation(
upper_bound_matrix,
upper_bound_vector,
len(self.spaces)))
for weight_for_sets in self.weight_set_mapping:
LOG.debug('Parameters for spaces set formation: %s',
weight_for_sets)
self._set_spaces_sets_by(weight_for_sets)
solution = linprog(
self.objective_function_coefficients,
A_eq=self.equality_constraint_matrix,
b_eq=self.equality_constraint_vector,
A_ub=upper_bound_matrix,
b_ub=upper_bound_vector,
bounds=self.bounds,
options={"disp": False})
# If solution is found we can finish attempts to find
# the best solution
if not solution.success:
break
LOG.debug("Solution: %s", solution)
self._check_errors(solution)
# Naive implementation of getting integer result
# from a linear programming algorithm, MIP
# (mixed integer programming) should be considered
# instead, but it may have a lot of problems (solution
# of such equations is NP-hard in some cases),
# for our practical purposes it's enough to round
# the number down, in this case we may get `n` megabytes
# unallocated, where n is len(spaces) * len(disks)
solution_vector = self._round_down(solution.x)
return self._convert_solution(solution_vector)
def _check_errors(self, solution):
if not solution.success:
raise errors.NoSolutionFound(
'Allocation is not possible '
'with specified constraints: {0}'.format(solution.message))
def _round_down(self, vector):
return [int(math.floor(f)) for f in vector]
def _init_min_max(self):
"""Create min and max constraints for each space.
In case of 2 disks and 2 spaces
For first space min_size >= 10 and max_size <= 20
1 * x1 + 0 * x2 + 1 * x3 + 0 * x4 >= 10
1 * x1 + 0 * x2 + 1 * x3 + 0 * x4 <= 20
For second space min_size >= 15 and max_size <= 30
0 * x1 + 1 * x2 + 0 * x3 + 1 * x4 >= 15
0 * x1 + 1 * x2 + 0 * x3 + 1 * x4 <= 30
"""
for space_idx, space in enumerate(self.spaces):
row = self._make_matrix_row()
max_size = getattr(space, 'max_size', None)
min_size = getattr(space, 'min_size', None)
for disk_idx in range(len(self.disks)):
row[disk_idx * len(self.spaces) + space_idx] = 1
if min_size is not None:
self.lower_bound_constraint_matrix.append(row)
self.lower_bound_constraint_vector.append(min_size)
if max_size is not None:
self.upper_bound_constraint_matrix.append(row)
self.upper_bound_constraint_vector.append(max_size)
def _get_spaces_sets_by(self, criteria):
return [i[1] for i in self._get_sets_by(criteria)]
def _get_sets_by(self, criteria):
def get_values(space):
return [getattr(space, c, None) for c in criteria]
grouped_spaces = itertools.groupby(
sorted(self.spaces, key=get_values),
key=get_values)
return [(k, list(v)) for k, v in grouped_spaces]
def _set_spaces_sets_by(self, criteria):
self.weight_spaces_sets = self._get_spaces_sets_by(criteria)
def _refresh_weight(self):
"""Refresh weight.
Create weight constraints for spaces which have same
max constraint or for those which don't have it at all.
Lets say, second's space is equal to max of the third and fourth,
we will have next equation:
0 * x1 + (1 / weight) * x2 + (-1 / weight) * x3 +
0 * x4 + (1 / weight) * x5 + (-1 / weight) * x6 = 0
"""
DEFAULT_WEIGHT = 1
# Clean constraint matrix and vector from previous values
for idx in sorted(self.weight_equation_indexes, reverse=True):
del self.equality_constraint_matrix[idx]
del self.equality_constraint_vector[idx]
self.weight_equation_indexes = []
for spaces_set in self.weight_spaces_sets:
# Don't set weight if there is less than one space in the set
if len(spaces_set) < 2:
continue
first_weight = getattr(spaces_set[0], 'weight', DEFAULT_WEIGHT)
first_space_idx = self.spaces.index(spaces_set[0])
for space in spaces_set[1:]:
row = self._make_matrix_row()
weight = getattr(space, 'weight', DEFAULT_WEIGHT)
# If weight is 0, it doesn't make sense to set for such
# space a weight
if weight == 0:
continue
space_idx = self.spaces.index(space)
for disk_idx in range(len(self.disks)):
row_i = disk_idx * len(self.spaces)
row[row_i + first_space_idx] = 1 / first_weight
row[row_i + space_idx] = -1 / weight
self.weight_equation_indexes.append(
len(self.equality_constraint_matrix) - 1)
self.equality_constraint_matrix.append(row)
self.equality_constraint_vector = np.append(
self.equality_constraint_vector,
0)
def _make_matrix_row(self):
return np.zeros(self.x_amount)
def _make_upper_bound_constraint_matrix(self):
"""Creates upper bound constraint matrix.
Upper bound constraint matrix consist of upper bound
matrix and lower bound matrix witch changed sign.
"""
return (self.upper_bound_constraint_matrix +
[[-i for i in row]
for row in self.lower_bound_constraint_matrix])
def _make_upper_bound_constraint_vector(self):
"""Create upper bound constraint vector.
Upper bound constraint vector consist of upper bound and
lower bound, with changed sign.
"""
return (self.upper_bound_constraint_vector +
[-i for i in self.lower_bound_constraint_vector])
solution = self.solver.solve()
LOG.debug('Static allocation schema: \n%s', solution)
return self._convert_solution(solution)
def _convert_solution(self, solution_vector):
# TODO(eli): convertation logic should be moved to solvers,
# as result Solver object should be returned and used
result = []
spaces_grouped_by_disk = list(utils.grouper(
solution_vector,
len(self.spaces)))
for disk_i in range(len(self.disks)):
disk_id = self.disks[disk_i].id
len(self.dynamic_schema.spaces)))
for disk_i in range(len(self.dynamic_schema.disks)):
disk_id = self.dynamic_schema.disks[disk_i].id
disk = {'disk_id': disk_id,
'size': self.disks[disk_i].size,
'size': self.dynamic_schema.disks[disk_i].size,
'spaces': []}
spaces_for_disk = spaces_grouped_by_disk[disk_i]
for space_i, space_size in enumerate(spaces_for_disk):
disk['spaces'].append({
'space_id': self.spaces[space_i].id,
'space_id': self.dynamic_schema.spaces[space_i].id,
'size': space_size})
result.append(disk)
return result
def _init_equation(self, disks, spaces):
for d in disks:
# Initialize constraints, each row in the matrix should
# be equal to size of the disk
self.equality_constraint_vector = np.append(
self.equality_constraint_vector,
d.size)
# Initialize the matrix
# In case of 2 spaces and 3 disks the result should be:
# [[1, 1, 0, 0, 0, 0],
# [0, 0, 1, 1, 0, 0],
# [0, 0, 0, 0, 1, 1]]
#
# Explanation of the first row
# [1, - x1 multiplier, size of space 1 on the first disk
# 1, - x2 multiplier, size of space 2 on the first disk
# 0, - x3 multiplier, size of space 1 on 2nd disk, 0 for the first
# 0, - x4 multiplier, size of space 2 on 2nd disk, 0 for the first
# 0, - x5 multiplier, size of space 1 on 3rd disk, 0 for the first
# 0] - x6 multiplier, size of space 2 on 3rd disk, 0 for the first
equality_matrix_row = self._make_matrix_row()
# Set first len(spaces) elements to 1
equality_matrix_row = utils.shift(
equality_matrix_row,
len(spaces),
val=1)
for _ in range(len(disks)):
self.equality_constraint_matrix.append(equality_matrix_row)
equality_matrix_row = utils.shift(
equality_matrix_row,
len(spaces),
val=0)
# Size of each space should be more or equal to 0
for _ in range(self.x_amount):
self._add_bound(0, None)
def _init_objective_function_coefficient(self):
# Amount of coefficients is equal to amount of x
c_amount = self.x_amount
# We want spaces to be allocated on disks
# in order which user specified them in the schema.
# In order to do that, we set coefficients
# higher for those spaces which defined earlier
# in the list
# TODO(eli): describe why we should use special sequence
# as order coefficients
coefficients = [1.0 / i for i in CrossSumInequalitySequence(c_amount)]
NONE_ORDER_COEFF = 1
SET_COEFF = 2
space_sets = self._get_spaces_sets_by(['best_with_disks'])
# A list of disks ids which are not selected for specific spaces
all_disks_ids = [i for i in range(len(self.disks))]
used_disks_ids = []
for k, space in self._get_sets_by(['best_with_disks']):
if k[0]:
used_disks_ids.extend(list(k[0]))
not_best_disks = list(set(all_disks_ids) - set(used_disks_ids))
for i_set, space_set in enumerate(space_sets):
for space in space_set:
s_i = self.spaces.index(space)
for d_i in range(len(self.disks)):
c_i = len(self.spaces) * d_i + s_i
# Set constant for none_order spaces
if getattr(space, 'none_order', False):
coefficients[c_i] = NONE_ORDER_COEFF
continue
if space.best_with_disks:
if d_i in space.best_with_disks:
coefficients[c_i] += SET_COEFF
else:
# If current disk is not in the set, set it to 0
# TODO(eli): isn't it better to leave there order
# coefficient?
# coefficients[c_i] = 0
pass
else:
# Don't allcoate coefficient for the spaces
# which have no best_with_disks, on best_with_disks
if d_i in not_best_disks:
coefficients[c_i] += SET_COEFF
# By default the algorithm tries to minimize the solution
# we should invert sign, in order to make it a maximization
# function, because we want disks to be maximally allocated.
self.objective_function_coefficients = [-c for c in coefficients]
def _add_bound(self, min_, max_):
np.append(self.bounds, (min_, max_))

6
bareon_allocator/objects/space.py
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@ -24,14 +24,16 @@ class Space(BaseObject):
'min_size': 0,
'max_size': None,
'best_with_disks': set([]),
'weight': 1
'weight': 1,
'none_order': False,
'type': None
}
required = ['id', 'type']
def __init__(self, **kwargs):
super(Space, self).__init__(**kwargs)
# Exact size should be repreneted as min_size and max_size
# Exact size should be represented as min_size and max_size
if kwargs.get('size'):
self.min_size = kwargs.get('size')
self.max_size = kwargs.get('size')

6
bareon_allocator/parsers/dynamic_schema_parser.py
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@ -70,13 +70,13 @@ class DynamicSchemaParser(object):
for i, space in enumerate(spaces):
if space.get('best_with_disks'):
disks_idx = set()
disks_ids = set()
for disk in space['best_with_disks']:
try:
disks_idx.add(self.raw_disks.index(disk))
disks_ids.add(disk['id'])
except ValueError as exc:
LOG.warn('Warning: %s', exc)
spaces[i]['best_with_disks'] = disks_idx
spaces[i]['best_with_disks'] = disks_ids
return spaces

24
bareon_allocator/solvers/__init__.py Normal file
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@ -0,0 +1,24 @@
# -*- coding: utf-8 -*-
# Copyright 2016 Mirantis, Inc.
#
# 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
#
# http://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.
# flake8: noqa
from bareon_allocator.solvers.base import BaseSolver
from bareon_allocator.solvers.linear_program import LinearProgram
from bareon_allocator.solvers.linear_programming_scipy_solver \
import LinearProgrammingScipySolver
from bareon_allocator.solvers.linear_program_creator \
import LinearProgramCreator

38
bareon_allocator/solvers/base.py Normal file
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@ -0,0 +1,38 @@
# -*- coding: utf-8 -*-
# Copyright 2016 Mirantis, Inc.
#
# 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
#
# http://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.
import abc
import six
@six.add_metaclass(abc.ABCMeta)
class BaseSolver(object):
"""Base class for Bareon Allocator Objects."""
def __init__(self, linear_program):
"""Initialize object.
:param linear_program: `class`:LinearProgram object
"""
self.linear_program = linear_program
@abc.abstractmethod
def solve(self):
"""Returns solution hash.
:raises: errors.NoSolutionFound
"""

97
bareon_allocator/solvers/linear_program.py Normal file
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@ -0,0 +1,97 @@
# -*- coding: utf-8 -*-
# Copyright 2016 Mirantis, Inc.
#
# 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
#
# http://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.
class LinearProgram(object):
"""LinearProgram object is abstract way to describe linear program."""
MAXIMIZE = 'maximize'
MINIMIZE = 'minimize'
# Linear Program
LP_TYPE_LP = 'lp'
# Mixed Integer Program
LP_TYPE_MIP = 'mip'
def __init__(
self,
x_amount=0,
optimization_type=MAXIMIZE,
lp_type=LP_TYPE_LP,
objective_function_coefficients=None,
equality_constraint_matrix=None,
lower_constraint_matrix=None,
upper_constraint_matrix=None,
equality_constraint_vector=None,
lower_constraint_vector=None,
upper_constraint_vector=None):
self.lp_type = lp_type
self.objective_function_optimization_type = optimization_type
# Coefficients of the linear objective minimization function.
# During iteration over vertexes the function is used to identify
# if current solution (vertex) satisfies the equation more, than
# previous one.
# Example of equation: c[0]*x1 + c[1]*x2
self.objective_function_coefficients = objective_function_coefficients
# Matrices which, gives values of the equality/inequality
# constraints, when multiplied by x.
self.equality_constraint_matrix = equality_constraint_matrix
self.lower_constraint_matrix = lower_constraint_matrix
self.upper_constraint_matrix = upper_constraint_matrix
# Vectors in combination with equality matrices give
# equality/inequality system of linear equations.
self.equality_constraint_vector = equality_constraint_vector
self.lower_constraint_vector = lower_constraint_vector
self.upper_constraint_vector = upper_constraint_vector
# Amount unknown of variables.
self.x_amount = x_amount
# A list of tuples which represents min and max possible values for
# each variable.
self.bounds = [(0, None) for _ in xrange(self.x_amount)]
def minimize_objective_function(self):
"""Minimize objective function."""
self.objective_function_optimization_type = self.MINIMIZE
def maximize_objective_function(self):
"""Maximize objective function."""
self.objective_function_optimization_type = self.MAXIMIZE
def set_type_lp(self):
"""Set type of linear program to Linear Program.
Is default, produces real number result, without any integer
constraints.
"""
self.lp_type = self.LP_TYPE_LP
def set_type_mip(self):
""""Set type of linear program to Mixed Integer Program.
This type may include integer constraints, as result wider range of
operations may be available.
Note: Not all linear programming solvers support this type.
See: https://en.wikipedia.org/wiki/Integer_programming
"""
self.lp_type = self.LP_TYPE_MIP

331
bareon_allocator/solvers/linear_program_creator.py Normal file
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@ -0,0 +1,331 @@
# -*- coding: utf-8 -*-
# Copyright 2016 Mirantis, Inc.
#
# 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
#
# http://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.
import itertools
from bareon_allocator.sequences import CrossSumInequalitySequence
from bareon_allocator.solvers.linear_program import LinearProgram
class LinearProgramCreator(object):
"""Creates LinearProgram based on DynamicSchema object."""
NONE_ORDER_COEFFICIENT = 1
SET_COEFFICIENT = 2
def __init__(self,
dynamic_schema,
weight_sets_criteria=[
'min_size',
'max_size',
'best_with_disks']):
"""Initializes the object.
:param dynamic_schema: :class:`DynamicSchema` object
:param weight_sets_criteria: a list of strings, which represents
attributes of spaces based on which sets will be created to
make equations.
"""
self.weight_sets_criteria = weight_sets_criteria
self.disks = dynamic_schema.disks
self.spaces = dynamic_schema.spaces
self.spaces_len = len(self.spaces)
self.disks_len = len(self.disks)
# For each space, x (size of the space) is represented
# for each disk as separate variable, so for each
# disk we have len(spaces) * len(disks) sizes
self.x_amount = self.disks_len * self.spaces_len
def linear_program(self):
"""Returns linear program object
:return: :class:`LinearProgram` linear program object
"""
space_size_equation = self._make_space_size_constraints()
disk_size_equation = self._make_disk_size_constraints()
equality_weight_equation = self._make_weight_constraints()
# Merge both equality and constraint vectors into a single dictionary
equations = self._merge_equations(space_size_equation,
disk_size_equation)
equations = self._merge_equations(equations,
equality_weight_equation)
objective_coefficients = self._make_objective_function_coefficient()
return LinearProgram(
x_amount=self.x_amount,
optimization_type=LinearProgram.MAXIMIZE,
objective_function_coefficients=objective_coefficients,
**equations)
def _make_space_size_constraints(self):
"""Create min and max constraints for each space.
In case of 2 disks and 2 spaces
For first space min_size >= 10 and max_size <= 20
1 * x1 + 0 * x2 + 1 * x3 + 0 * x4 >= 10
1 * x1 + 0 * x2 + 1 * x3 + 0 * x4 <= 20
For second space min_size >= 15 and max_size <= 30
0 * x1 + 1 * x2 + 0 * x3 + 1 * x4 >= 15
0 * x1 + 1 * x2 + 0 * x3 + 1 * x4 <= 30
"""
constraint_equation = {
'lower_constraint_matrix': [],
'lower_constraint_vector': [],
'upper_constraint_matrix': [],
'upper_constraint_vector': []}
for space_idx, space in enumerate(self.spaces):
row = self._make_matrix_row()
for disk_idx in range(self.disks_len):
row[disk_idx * self.spaces_len + space_idx] = 1
if space.min_size is not None:
constraint_equation['lower_constraint_matrix'].append(
row)
constraint_equation['lower_constraint_vector'].append(
space.min_size)
if space.max_size is not None:
constraint_equation['upper_constraint_matrix'].append(
row)
constraint_equation['upper_constraint_vector'].append(
space.max_size)
return constraint_equation
def _merge_equations(self, eq1, eq2):
"""Merges two equations into a single dictionary of equations.
:param eq1: equation dictionary, where key is a name of equation and
value is a vector or matrix
:param eq2: same as eq1
:return: merged equation
"""
result = {}
all_keys = set(eq1.keys() + eq2.keys())
for key in all_keys:
if eq2.get(key) and eq1.get(key):
# Merge if both have values
result[key] = eq1[key] + eq2[key]
elif eq2.get(key):
result[key] = eq2[key]
elif eq1.get(key):
result[key] = eq1[key]
return result
def _make_disk_size_constraints(self):
"""Creates equations based on disk sizes.
So solver will not allocate more then "disk size" space for each disk.
In case of 2 spaces and 3 disks the result should be:
[[1, 1, 0, 0, 0, 0],
[0, 0, 1, 1, 0, 0],
[0, 0, 0, 0, 1, 1]]
Explanation of the first row
[1, - x1 multiplier, size of space 1 on the first disk
1, - x2 multiplier, size of space 2 on the first disk
0, - x3 multiplier, size of space 1 on 2nd disk, 0 for the first
0, - x4 multiplier, size of space 2 on 2nd disk, 0 for the first
0, - x5 multiplier, size of space 1 on 3rd disk, 0 for the first
0] - x6 multiplier, size of space 2 on 3rd disk, 0 for the first
:return: equations, where key is a name of equation, value is a list
or vector
"""
constraint_equation = {
'upper_constraint_matrix': [],
'upper_constraint_vector': []}
for disk_idx in range(self.disks_len):
row = self._make_matrix_row()
for space_idx, space in enumerate(self.spaces):
row[disk_idx * self.spaces_len + space_idx] = 1
constraint_equation['upper_constraint_matrix'].append(row)
constraint_equation['upper_constraint_vector'].append(
self.disks[disk_idx].size)
return constraint_equation
def _make_weight_constraints(self):
"""Refresh weight.
Create weight constraints for spaces which have same
max constraint or for those which don't have it at all.
Lets say, second space is equal to the third, as the result
we will have next equation:
0 * x1 + (1 / weight) * x2 + (-1 / weight) * x3 +
0 * x4 + (1 / weight) * x5 + (-1 / weight) * x6 = 0
See "Weight" section in the documentation for details:
http://bareon-allocator.readthedocs.org/en
/latest/architecture.html#weight
TODO(eli): it should be not equality, but inequality with some
range, so we will not get fails every time exact constraint cannot be
satisfied.
"""
weight_equations = {
'equality_constraint_matrix': [],
'equality_constraint_vector': []}
weight_spaces_sets = self._get_spaces_sets_by(
self.weight_sets_criteria)
for spaces_set in weight_spaces_sets:
# Don't set weight if there is less than one space in the set
if len(spaces_set) < 2:
continue
first_weight = spaces_set[0].weight
first_space_idx = self.spaces.index(spaces_set[0])
for space in spaces_set[1:]:
row = self._make_matrix_row()
# If weight is 0, it doesn't make sense to set for such
# space a weight
if space.weight == 0:
continue
space_idx = self.spaces.index(space)
for disk_idx in range(self.disks_len):
row_i = disk_idx * len(self.spaces)
row[row_i + first_space_idx] = 1.0 / first_weight
row[row_i + space_idx] = -1.0 / space.weight
weight_equations['equality_constraint_matrix'].append(row)
weight_equations['equality_constraint_vector'].append(0)
return weight_equations
def _make_objective_function_coefficient(self):
"""Creates objective function coefficients.
We want spaces to be allocated on disks in order which user
specified them in the schema. In order to do that, we set
coefficients higher for those spaces which defined earlier in the
list.
:return: a vector of coefficients
"""
# Instead of just Integer sequence special type of sequence is being
# used, see documentation [1] for details.
# Every order coefficient should be between 0 and 1 (not included),
# in order to aviod having 1st element equal to 1, sequence should be
# started from 2nd element.
#
# [1] http://bareon-allocator.readthedocs.org/en
# /latest/architecture.html#ordering
seq = CrossSumInequalitySequence(self.x_amount + 1)
next(seq, None)
coefficients = [1.0 / i for i in seq]
space_sets = self._get_spaces_sets_by(['best_with_disks'])
no_best_disks = self._get_empty_sets_disks_ids(['best_with_disks'])
for i_set, space_set in enumerate(space_sets):
for space in space_set:
s_i = self.spaces.index(space)
for d_i, disk in enumerate(self.disks):
c_i = self.spaces_len * d_i + s_i
# Set constant for none_order spaces
if space.none_order:
coefficients[c_i] = self.NONE_ORDER_COEFFICIENT
continue
# If space does not belong to any set, order coefficient
# will be left without any additional coefficients.
if (space.best_with_disks and
disk.id in space.best_with_disks):
# If the space has "best disks" and current disk is
# in best disks list, add coefficient.
coefficients[c_i] += self.SET_COEFFICIENT
elif (not space.best_with_disks and
disk.id in no_best_disks):
# If the space does *not* have "best disks" and
# current disk is not in the list of "best disks" of
# any space, add set coefficient.
coefficients[c_i] += self.SET_COEFFICIENT
# By default the algorithm tries to minimize the solution
# we should invert sign, in order to make it a maximization
# function, because we want disks to be maximally allocated.
return [-c for c in coefficients]
def _get_empty_sets_disks_ids(self, criteria):
"""Get disks indexes which do not belong to set of any spaces.
:param criteria: a list of strings, with criteria by which sets has
to be created
:return: a list of disks indexes
"""
all_disks_ids = [d.id for d in self.disks]
used_disks_ids = []
for k, space in self._get_sets_by(criteria):
if k[0]:
used_disks_ids.extend(list(k[0]))
return list(set(all_disks_ids) - set(used_disks_ids))
def _get_spaces_sets_by(self, criteria):
"""Get all spaces which are used for sets.
:param criteria: a list of strings with attributes by which sets has
to be created
:return: a list of spaces lists, where each list item is represents
a set
"""
return [i[1] for i in self._get_sets_by(criteria)]
def _get_sets_by(self, criteria):
"""Makes sets based on criteria from space attributes.
:param criteria: a list of strings with attributes by which sets has
to be created
:return: a list of tuples, where first item are criteria, second
item is a list of spaces
"""
def get_values(space):
return [getattr(space, c, None) for c in criteria]
grouped_spaces = itertools.groupby(
sorted(self.spaces, key=get_values),
key=get_values)
return [(k, list(v)) for k, v in grouped_spaces]
def _make_matrix_row(self):
"""Make a matrix row
:return: a vector where all the items are 0
"""
return [0] * self.x_amount

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# -*- coding: utf-8 -*-
# Copyright 2016 Mirantis, Inc.
#
# 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
#
# http://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 scipy.optimize import linprog
from bareon_allocator import errors
from bareon_allocator.solvers import BaseSolver
from bareon_allocator.solvers import utils
class LinearProgrammingScipySolver(BaseSolver):
"""Linear programming allocator.
Use Linear Programming method [0] (the method itself has nothing to do
with computer-programming) in order to formulate and solve the problem
of spaces allocation on disks, with the best outcome.
In this implementation scipy is being used since it already implements
simplex algorithm to find the best feasible solution.
[0] https://en.wikipedia.org/wiki/Linear_programming
[1] http://docs.scipy.org/doc/scipy-0.16.0/reference/generated
/scipy.optimize.linprog.html
[2] https://en.wikipedia.org/wiki/Simplex_algorithm
"""
def solve(self):
"""Solves linear program.
:return: solution vector
"""
lp_solution = linprog(
self.linear_program.objective_function_coefficients,
A_eq=self.linear_program.equality_constraint_matrix or None,
b_eq=self.linear_program.equality_constraint_vector or None,
A_ub=self._make_upper_constraint_matrix() or None,
b_ub=self._make_upper_constraint_vector() or None,
bounds=self.linear_program.bounds,
options={"disp": False})
self._check_errors(lp_solution)
# Naive implementation of getting integer result
# from a linear programming algorithm, MIP
# (mixed integer programming) should be considered
# instead, but it may have a lot of problems (solution
# of such equations is NP-hard in some cases),
# for our practical purposes it's enough to round
# the number down, in this case we may get `n` megabytes
# unallocated, where n is len(spaces) * len(disks)
solution_vector = utils.round_vector_down(lp_solution.x)
return solution_vector
def _check_errors(self, solution):
"""Checks if solution is not found.
:param solution: solution object from scipy
:raises: errors.NoSolutionFound if solution is not found
"""
if not solution.success:
raise errors.NoSolutionFound(
'Allocation is not possible '
'with specified constraints: {0}'.format(solution.message))
def _make_upper_constraint_matrix(self):
"""Merges lower constraint matrix into upper."""
upper_constraint_matrix = []
if self.linear_program.upper_constraint_matrix:
upper_constraint_matrix.extend(
self.linear_program.upper_constraint_matrix)
if self.linear_program.lower_constraint_matrix:
# Swap sign for lower constraint matrix in order to make it
# upper bound instead of lower bound
upper_constraint_matrix.extend(
[-i for i in row] for row in
self.linear_program.lower_constraint_matrix)
return upper_constraint_matrix
def _make_upper_constraint_vector(self):
"""Merges lower constraint vector into upper."""
upper_constraint_vector = []
if self.linear_program.upper_constraint_vector:
upper_constraint_vector.extend(
self.linear_program.upper_constraint_vector)
if self.linear_program.lower_constraint_vector:
# Swap sign for items in the vector to make it upper bound
# instead of lower bound
upper_constraint_vector.extend(
[-i for i in self.linear_program.lower_constraint_vector])
return upper_constraint_vector

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# -*- coding: utf-8 -*-
# Copyright 2016 Mirantis, Inc.
#
# 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
#
# http://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.
import math
def round_vector_down(vector):
"""Rounds items in the vector down.
:param vector: vector of float numbers
:return: a list of integers
"""
return [int(math.floor(f)) for f in vector]

28
bareon_allocator/tests/test_bareon_dynamic_allocator.py
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@ -1,28 +0,0 @@
# -*- coding: utf-8 -*-
# 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
#
# http://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.
"""
test_bareon_allocator
----------------------------------
Tests for `bareon_allocator` module.
"""
from bareon_allocator.tests import base
class TestBareon_dynamic_allocator(base.TestCase):
def test_something(self):
pass

26
bareon_allocator/tests/test_objects_disk.py Normal file
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# -*- coding: utf-8 -*-
# Copyright 2016 Mirantis, Inc.
#
# 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
#
# http://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 bareon_allocator.objects import Disk
from bareon_allocator.tests import base
class TestObjectsDisk(base.TestCase):
def test_object_creation(self):
disk = Disk(id=10, size=42)
self.assertEqual(disk.id, 10)
self.assertEqual(disk.size, 42)

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bareon_allocator/tests/test_objects_space.py Normal file
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# -*- coding: utf-8 -*-
# Copyright 2016 Mirantis, Inc.
#
# 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
#
# http://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 bareon_allocator import errors
from bareon_allocator.objects import Space
from bareon_allocator.tests import base
class TestObjectsSpace(base.TestCase):
def test_object_creation(self):
space = Space(id=10,
min_size=1,
max_size=2,
type='lv',
best_with_disks=[1, 2, 3])
self.assertEqual(space.id, 10)
self.assertEqual(space.min_size, 1)
self.assertEqual(space.max_size, 2)
self.assertEqual(space.type, 'lv')
self.assertEqual(space.best_with_disks, [1, 2, 3])
self.assertEqual(space.weight, 1)
self.assertEqual(space.none_order, False)
def test_size_sets_min_and_max(self):
space = Space(id=10, type='lv', size=15)
self.assertEqual(space.min_size, 15)
self.assertEqual(space.max_size, 15)
def test_fail_if_no_type(self):
self.assertRaises(errors.InvalidData, Space, id=11)

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bareon_allocator/tests/test_parsers_dynamic_schema_parser.py Normal file
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# -*- coding: utf-8 -*-
# Copyright 2016 Mirantis, Inc.
#
# 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
#
# http://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 bareon_allocator.parsers import DynamicSchemaParser
from bareon_allocator.tests import base
class TestParsersDynamicSchemaParser(base.TestCase):
def setUp(self):
super(TestParsersDynamicSchemaParser, self).setUp()
hw_info = {
'disks': [
{'id': 'sda', 'size': 100},
{'id': 'sdb', 'size': 42},
{'id': 'sdc', 'size': 42}]}
schema = [
{'id': 'lv1',
'type': 'lv',
'max_size': 1},
{'id': 'lv2',
'type': 'lv',
'max_size': 1,
'best_with_disks': 'yaql=$.disks.where($.size=42)'},
{'id': 'vg1',
'type': 'vg'}]
self.dynamic_schema_parser = DynamicSchemaParser(hw_info, schema)
def test_unallocated_is_added(self):
unallocated = filter(lambda s: s.id == 'unallocated',
self.dynamic_schema_parser.spaces)
self.assertEqual(len(unallocated), 1)
self.assertEqual(unallocated[0].type, 'unallocated')
self.assertEqual(unallocated[0].none_order, True)
self.assertEqual(unallocated[0].weight, 0)
def test_aggregation_spaces_are_not_in_the_list(self):
spaces = filter(lambda d: d.type == 'vg',
self.dynamic_schema_parser.spaces)
self.assertEqual(len(spaces), 0)
def test_sets_best_with_disks_ids(self):
spaces = filter(lambda s: s.id == 'lv2',
self.dynamic_schema_parser.spaces)
self.assertEqual(len(spaces), 1)
self.assertEqual(spaces[0].best_with_disks, {'sdb', 'sdc'})

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bareon_allocator/tests/test_parsers_expressions.py Normal file
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# -*- coding: utf-8 -*-
# Copyright 2016 Mirantis, Inc.
#
# 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
#
# http://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 bareon_allocator.parsers import ExpressionsParser
from bareon_allocator.tests import base
class TestParsersExpressions(base.TestCase):
def test_substitutes_value_recursively(self):
parsed = ExpressionsParser(
[{'key1': 'key2'},
{'list': [{'list_key': 'yaql=$.some_key'}]}],
{'some_key': 'some_value'}).parse()
self.assertEqual(
parsed,
[{'key1': 'key2'},
{'list': [{'list_key': 'some_value'}]}])

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bareon_allocator/tests/test_solvers_linear_program.py Normal file
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# -*- coding: utf-8 -*-
# Copyright 2016 Mirantis, Inc.
#
# 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
#
# http://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 bareon_allocator.solvers import LinearProgram
from bareon_allocator.tests import base
class TestSolversLinearProgram(base.TestCase):
def setUp(self):
super(TestSolversLinearProgram, self).setUp()
self.lp = LinearProgram(
x_amount=3,
objective_function_coefficients=[1, 0, 0],
equality_constraint_matrix=[[1, 2, 3], [4, 5, 6]],
lower_constraint_matrix=[[7, 8, 9], [10, 11, 12]],
upper_constraint_matrix=[[13, 14, 15], [16, 17, 18]],
equality_constraint_vector=[1, 2, 3],
lower_constraint_vector=[3, 4, 5],
upper_constraint_vector=[6, 7, 8])
def test_values_are_set(self):
self.assertEqual(self.lp.x_amount, 3)
self.assertEqual(
self.lp.objective_function_coefficients,
[1, 0, 0])
self.assertEqual(
self.lp.equality_constraint_matrix,
[[1, 2, 3], [4, 5, 6]])
self.assertEqual(
self.lp.lower_constraint_matrix,
[[7, 8, 9], [10, 11, 12]])
self.assertEqual(
self.lp.upper_constraint_matrix,
[[13, 14, 15], [16, 17, 18]])
self.assertEqual(
self.lp.equality_constraint_vector,
[1, 2, 3])
self.assertEqual(
self.lp.lower_constraint_vector,
[3, 4, 5])
self.assertEqual(
self.lp.upper_constraint_vector,
[6, 7, 8])
def test_default_values_are_set(self):
self.assertEqual(self.lp.lp_type, self.lp.LP_TYPE_LP)
self.assertEqual(self.lp.objective_function_optimization_type,
self.lp.MAXIMIZE)
self.assertEqual(self.lp.bounds, [(0, None), (0, None), (0, None)])

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# -*- coding: utf-8 -*-
# Copyright 2016 Mirantis, Inc.
#
# 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
#
# http://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.
import mock
from bareon_allocator.solvers import LinearProgramCreator
from bareon_allocator.tests import base
class TestSolversLinearProgramCreator(base.TestCase):
def create_lp(self, spaces_info=[], disks_info=[]):
dynamic_schema_mock = mock.MagicMock(spaces=[], disks=[])
for s in spaces_info:
dynamic_schema_mock.spaces.append(mock.MagicMock(**s))
for d in disks_info:
dynamic_schema_mock.disks.append(mock.MagicMock(**d))
return LinearProgramCreator(dynamic_schema_mock).linear_program()
def assert_lower_eq_exists(self, lp, eq, value):
self.assert_eq_and_value(
lp.lower_constraint_matrix,
lp.lower_constraint_vector,
eq,
value)
def assert_upper_eq_exists(self, lp, eq, value):
self.assert_eq_and_value(
lp.upper_constraint_matrix,
lp.upper_constraint_vector,
eq,
value)
def assert_eq_exists(self, lp, eq, value):
self.assert_eq_and_value(
lp.equality_constraint_matrix,
lp.equality_constraint_vector,
eq,
value)
def assert_eq_and_value(self, eq_list, eq_vector, expected_eq, value):
eq = None
i_eq = None
for i, _eq in enumerate(eq_list):
if _eq == expected_eq:
eq = _eq
i_eq = i
break
self.assertIsNotNone(eq, 'Cannot find equation')
self.assertEqual(eq_vector[i_eq], value,
'Value of equation does not match to expected')
def test_min_size_equations(self):
lp = self.create_lp(
spaces_info=[
{'min_size': 10},
{'min_size': 20},
{'min_size': 0}],
disks_info=[
{'id': 'sda', 'size': 50},
{'id': 'sda', 'size': 60}])
self.assert_lower_eq_exists(lp, [1, 0, 0, 1, 0, 0], 10)
self.assert_lower_eq_exists(lp, [0, 1, 0, 0, 1, 0], 20)
self.assert_lower_eq_exists(lp, [0, 0, 1, 0, 0, 1], 0)
def test_max_size_equations(self):
lp = self.create_lp(
spaces_info=[
{'max_size': 10},
{'max_size': 20},
{'min_size': 0}],
disks_info=[
{'id': 'sda', 'size': 50},
{'id': 'sda', 'size': 60}])
self.assert_upper_eq_exists(lp, [1, 0, 0, 1, 0, 0], 10)
self.assert_upper_eq_exists(lp, [0, 1, 0, 0, 1, 0], 20)
def test_disk_size_equations(self):
lp = self.create_lp(
spaces_info=[
{'max_size': 10},
{'max_size': 20},
{'min_size': 0}],
disks_info=[
{'id': 'sda', 'size': 50},
{'id': 'sda', 'size': 60}])
self.assert_upper_eq_exists(lp, [1, 1, 1, 0, 0, 0], 50)
self.assert_upper_eq_exists(lp, [0, 0, 0, 1, 1, 1], 60)
def test_weight_eq(self):
lp = self.create_lp(
spaces_info=[
{'id': 'v1', 'min_size': 20, 'max_size': None,
'best_with_disks': [], 'weight': 10},
{'id': 'v2', 'min_size': 20, 'max_size': None,
'best_with_disks': [], 'weight': 5},
{'id': 'v3', 'min_size': 30, 'max_size': None,
'best_with_disks': ['sda'], 'weight': 1},
{'id': 'v4', 'min_size': 30, 'max_size': None,
'best_with_disks': ['sda'], 'weight': 1}],
disks_info=[
{'id': 'sda', 'size': 100},
{'id': 'sdb', 'size': 200},
{'id': 'sdc', 'size': 300}])
self.assert_eq_exists(
lp,
[0.1, -0.2, 0, 0,
0.1, -0.2, 0, 0,
0.1, -0.2, 0, 0],
0)
self.assert_eq_exists(
lp,
[0, 0, 1.0, -1.0,
0, 0, 1.0, -1.0,
0, 0, 1.0, -1.0],
0)
def test_objective_function_equation(self):
lp = self.create_lp(
spaces_info=[
{'id': 'v0', 'min_size': 20, 'max_size': None,
'best_with_disks': [],
'weight': 10, 'none_order': False},
{'id': 'v1', 'min_size': 20, 'max_size': None,
'best_with_disks': [],
'weight': 5, 'none_order': False},
{'id': 'v2', 'min_size': 30, 'max_size': None,
'best_with_disks': ['sda'],
'weight': 1, 'none_order': False},
{'id': 'v3', 'min_size': 30, 'max_size': None,
'best_with_disks': ['sda'],
'weight': 1, 'none_order': False}],
disks_info=[
{'id': 'sda', 'size': 100},
{'id': 'sdb', 'size': 200},
{'id': 'sdc', 'size': 300}])
seq = [2, 4, 6, 9, 12, 16, 20, 25, 30, 36, 42, 49]
reverse_seq = [-1.0 / s for s in seq]
weight_indexes = [
2, # v2, sda
3, # v3, sda
4, # v0, sdb
5, # v1, sdb
8, # v0, sdc
9] # v1, sdc
for idx in weight_indexes:
# Substitute "set" coefficient
reverse_seq[idx] -= 2
self.assertEqual(
lp.objective_function_coefficients,
reverse_seq)

55
bareon_allocator/tests/test_solvers_linear_programming_scipy_solver.py Normal file
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@ -0,0 +1,55 @@
# -*- coding: utf-8 -*-
# Copyright 2016 Mirantis, Inc.
#
# 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
#
# http://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 bareon_allocator import errors
from bareon_allocator.solvers.linear_program import LinearProgram
from bareon_allocator.solvers.linear_programming_scipy_solver \
import LinearProgrammingScipySolver
from bareon_allocator.tests import base
class TestSolversLinearProgrammingScipySolver(base.TestCase):
def test_solves_lp(self):
# x = 1
# y = 1
# z + j >= 2
# x + y + z + j <= 4
lp = LinearProgram(
equality_constraint_matrix=[[1, 0, 0, 0], [0, 1, 0, 0]],
equality_constraint_vector=[1, 1],
lower_constraint_matrix=[[0, 0, 1, 1]],
lower_constraint_vector=[2],
upper_constraint_matrix=[[1, 1, 1, 1]],
upper_constraint_vector=[4],
objective_function_coefficients=[0, 0, 0, 0],
x_amount=4)
solver = LinearProgrammingScipySolver(lp)
self.assertEqual(
solver.solve(),
[1, 1, 2, 0])
def test_raises_error(self):
# 0 + 0 = 2
lp = LinearProgram(
equality_constraint_matrix=[[0, 0]],
equality_constraint_vector=[1],
objective_function_coefficients=[0, 0],
x_amount=2)
solver = LinearProgrammingScipySolver(lp)
self.assertRaises(errors.NoSolutionFound, solver.solve)

27
bareon_allocator/tests/test_solvers_utils.py Normal file
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@ -0,0 +1,27 @@
# -*- coding: utf-8 -*-
# Copyright 2016 Mirantis, Inc.
#
# 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
#
# http://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 bareon_allocator.solvers.utils import round_vector_down
from bareon_allocator.tests import base
class TestSolversUtils(base.TestCase):
def test_round_down(self):
self.assertEqual(
round_vector_down([1.9, 2.0, 3.1]),
[1, 2, 3])

2
doc/source/architecture.rst
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@ -673,7 +673,7 @@ or
#. Build sets according to selected disks, in our case we have two sets, **hdd** and **ssd** disks.
#. For spaces which belong to specific set of disks add **1** to a coefficient which represents this space on a disk from the set.
#. If space does not belong to the set of disks, add **0**.
#. Spaces which do not belong to any disks sets are assigned to set of disks which is left, in our case it is **hdd** disks set.
To make sure that spaces are always (unless size constraints are not violated) allocated on the disks which they best suited with,
we automatically add a special artificial volume **unallocated**, whose coefficient is always **1**, and in this case we should change