Class: ConsistentHashing::Continuum

Inherits:
Object
  • Object
show all
Defined in:
lib/consistent_hashing.rb

Constant Summary collapse

DEFAULT_ANCHORS_PER_SERVER = 
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Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(servers, anchors_per_server = DEFAULT_ANCHORS_PER_SERVER) ⇒ Continuum

Returns a new instance of Continuum.



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# File 'lib/consistent_hashing.rb', line 35

def initialize(servers, anchors_per_server=DEFAULT_ANCHORS_PER_SERVER)
  @servers = servers
  @anchors_per_server = anchors_per_server
  @hasher = JenkinsOneAtATime
  create_all_anchors!
end

Instance Attribute Details

#anchors ⇒ Object

Returns the value of attribute anchors.



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# File 'lib/consistent_hashing.rb', line 28

def anchors
  @anchors
end

#anchors_per_server ⇒ Object

Returns the value of attribute anchors_per_server.



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# File 'lib/consistent_hashing.rb', line 28

def anchors_per_server
  @anchors_per_server
end

#hasher ⇒ Object

Returns the value of attribute hasher.



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# File 'lib/consistent_hashing.rb', line 28

def hasher
  @hasher
end

#servers ⇒ Object

Returns the value of attribute servers.



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# File 'lib/consistent_hashing.rb', line 28

def servers
  @servers
end

Instance Method Details

#expected_load ⇒ Object 



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# File 'lib/consistent_hashing.rb', line 50

def expected_load
  point = 0
  address_to_load = Hash.new(0)
  
  anchors.each do |anchor|
    address_to_load[anchor.server.address] += (anchor.value - point)
    point = anchor.value
  end
  
  address_to_load[anchors.first.server.address] += (1.0 - point)
  address_to_load
end

#find_server(search_value) ⇒ Object 



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# File 'lib/consistent_hashing.rb', line 42

def find_server(search_value)
  closest_anchor(search_value).server
end

#hash_to_unit_circle(key) ⇒ Object 



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# File 'lib/consistent_hashing.rb', line 46

def hash_to_unit_circle(key)
  hasher.hash_to_unit_circle(key)
end

#to_s ⇒ Object 



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# File 'lib/consistent_hashing.rb', line 63

def to_s
  anchors.map{|p| p.to_s}.join("\n")
end