Class: Dalli::Ring
- Inherits:
-
Object
- Object
- Dalli::Ring
- Defined in:
- lib/dalli/ring.rb
Defined Under Namespace
Classes: Entry
Constant Summary collapse
- POINTS_PER_SERVER =
this is the default in libmemcached
160
Instance Attribute Summary collapse
-
#continuum ⇒ Object
Returns the value of attribute continuum.
-
#servers ⇒ Object
Returns the value of attribute servers.
Instance Method Summary collapse
-
#initialize(servers, options) ⇒ Ring
constructor
A new instance of Ring.
- #lock ⇒ Object
- #server_for_key(key) ⇒ Object
Constructor Details
#initialize(servers, options) ⇒ Ring
Returns a new instance of Ring.
11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 |
# File 'lib/dalli/ring.rb', line 11 def initialize(servers, ) @servers = servers @continuum = nil if servers.size > 1 total_weight = servers.inject(0) { |memo, srv| memo + srv.weight } continuum = [] servers.each do |server| entry_count_for(server, servers.size, total_weight).times do |idx| hash = Digest::SHA1.hexdigest("#{server.name}:#{idx}") value = Integer("0x#{hash[0..7]}") continuum << Dalli::Ring::Entry.new(value, server) end end @continuum = continuum.sort_by(&:value) end threadsafe! unless [:threadsafe] == false @failover = [:failover] != false end |
Instance Attribute Details
#continuum ⇒ Object
Returns the value of attribute continuum.
9 10 11 |
# File 'lib/dalli/ring.rb', line 9 def continuum @continuum end |
#servers ⇒ Object
Returns the value of attribute servers.
9 10 11 |
# File 'lib/dalli/ring.rb', line 9 def servers @servers end |
Instance Method Details
#lock ⇒ Object
49 50 51 52 53 54 55 56 |
# File 'lib/dalli/ring.rb', line 49 def lock @servers.each(&:lock!) begin return yield ensure @servers.each(&:unlock!) end end |
#server_for_key(key) ⇒ Object
31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 |
# File 'lib/dalli/ring.rb', line 31 def server_for_key(key) if @continuum hkey = hash_for(key) 20.times do |try| entryidx = binary_search(@continuum, hkey) server = @continuum[entryidx].server return server if server.alive? break unless @failover hkey = hash_for("#{try}#{key}") end else server = @servers.first return server if server && server.alive? end raise Dalli::RingError, "No server available" end |