1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
|
RSpec.shared_examples 'exchanger method with indefinite timeout' do
before(:each) do
subject # ensure proper initialization
end
it 'blocks indefinitely' do
latch_1 = Concurrent::CountDownLatch.new
latch_2 = Concurrent::CountDownLatch.new
t = in_thread do
latch_1.count_down
subject.send(method_name, 0.1)
latch_2.count_down
end
is_sleeping t
expect(latch_1.count).to eq 0
expect(latch_2.count).to eq 1
end
it 'receives the other value' do
first_value = nil
second_value = nil
latch = Concurrent::CountDownLatch.new(2)
in_thread { first_value = subject.send(method_name, 2); latch.count_down }
in_thread { second_value = subject.send(method_name, 4); latch.count_down }
latch.wait(1)
expect(get_value(first_value)).to eq 4
expect(get_value(second_value)).to eq 2
end
it 'can be reused' do
first_value = nil
second_value = nil
latch_1 = Concurrent::CountDownLatch.new(2)
latch_2 = Concurrent::CountDownLatch.new(2)
in_thread { first_value = subject.send(method_name, 1); latch_1.count_down }
in_thread { second_value = subject.send(method_name, 0); latch_1.count_down }
latch_1.wait(1)
in_thread { first_value = subject.send(method_name, 10); latch_2.count_down }
in_thread { second_value = subject.send(method_name, 12); latch_2.count_down }
latch_2.wait(1)
expect(get_value(first_value)).to eq 12
expect(get_value(second_value)).to eq 10
end
end
RSpec.shared_examples 'exchanger method with finite timeout' do
it 'blocks until timeout' do
duration = Concurrent::TestHelpers.monotonic_interval do
begin
subject.send(method_name, 2, 0.1)
rescue Concurrent::TimeoutError
# do nothing
end
end
expect(duration).to be_within(0.05).of(0.1)
end
it 'receives the other value' do
first_value = nil
second_value = nil
latch = Concurrent::CountDownLatch.new(2)
in_thread { first_value = subject.send(method_name, 2, 1); latch.count_down }
in_thread { second_value = subject.send(method_name, 4, 1); latch.count_down }
latch.wait(1)
expect(get_value(first_value)).to eq 4
expect(get_value(second_value)).to eq 2
end
it 'can be reused' do
first_value = nil
second_value = nil
latch_1 = Concurrent::CountDownLatch.new(2)
latch_2 = Concurrent::CountDownLatch.new(2)
in_thread { first_value = subject.send(method_name, 1, 1); latch_1.count_down }
in_thread { second_value = subject.send(method_name, 0, 1); latch_1.count_down }
latch_1.wait(1)
in_thread { first_value = subject.send(method_name, 10, 1); latch_2.count_down }
in_thread { second_value = subject.send(method_name, 12, 1); latch_2.count_down }
latch_2.wait(1)
expect(get_value(first_value)).to eq 12
expect(get_value(second_value)).to eq 10
end
end
RSpec.shared_examples 'exchanger method cross-thread interactions' do
it 'when first, waits for a second' do
first_value = nil
second_value = nil
latch = Concurrent::CountDownLatch.new(1)
t1 = in_thread do
first_value = subject.send(method_name, :foo, 1)
latch.count_down
end
t1.join(0.1)
second_value = subject.send(method_name, :bar, 0)
latch.wait(1)
expect(get_value(first_value)).to eq :bar
expect(get_value(second_value)).to eq :foo
end
it 'allows multiple firsts to cancel if necessary', notravis: true do
first_value = nil
second_value = nil
cancels = 3
cancel_latch = Concurrent::CountDownLatch.new(cancels)
success_latch = Concurrent::CountDownLatch.new(1)
threads = cancels.times.collect do
in_thread do
begin
first_value = subject.send(method_name, :foo, 0.1)
rescue Concurrent::TimeoutError
# suppress
ensure
cancel_latch.count_down
end
end
end
threads.each { |t| t.join(1) }
cancel_latch.wait(1)
t1 = in_thread do
first_value = subject.send(method_name, :bar, 1)
success_latch.count_down
end
t1.join(0.1)
second_value = subject.send(method_name, :baz, 0)
success_latch.wait(1)
expect(get_value(first_value)).to eq :baz
expect(get_value(second_value)).to eq :bar
end
end
RSpec.shared_examples :exchanger do
context '#exchange' do
let!(:method_name) { :exchange }
def get_value(result)
result
end
it_behaves_like 'exchanger method with indefinite timeout'
it_behaves_like 'exchanger method with finite timeout'
it_behaves_like 'exchanger method cross-thread interactions'
end
context '#exchange!' do
let!(:method_name) { :exchange! }
def get_value(result)
result
end
it_behaves_like 'exchanger method with indefinite timeout'
it_behaves_like 'exchanger method with finite timeout'
it_behaves_like 'exchanger method cross-thread interactions'
end
context '#try_exchange' do
let!(:method_name) { :try_exchange }
def get_value(result)
result.value
end
it_behaves_like 'exchanger method with indefinite timeout'
it_behaves_like 'exchanger method with finite timeout'
it_behaves_like 'exchanger method cross-thread interactions'
end
end
module Concurrent
RSpec.describe RubyExchanger do
it_behaves_like :exchanger
if Concurrent.on_cruby?
specify 'stress test', notravis: true do
thread_count = 100
exchange_count = 100
latch = Concurrent::CountDownLatch.new(thread_count)
good = Concurrent::AtomicFixnum.new(0)
bad = Concurrent::AtomicFixnum.new(0)
ugly = Concurrent::AtomicFixnum.new(0)
thread_count.times.collect do |i|
in_thread do
exchange_count.times do |j|
begin
result = subject.exchange!(i, 1)
result == i ? ugly.up : good.up
rescue Concurrent::TimeoutError
bad.up
end
end
latch.count_down
end
end
latch.wait
puts "Good: #{good.value}, Bad (timeout): #{bad.value}, Ugly: #{ugly.value}"
expect(good.value + bad.value + ugly.value).to eq thread_count * exchange_count
expect(ugly.value).to eq 0
end
end
end
if defined? JavaExchanger
RSpec.describe JavaExchanger do
it_behaves_like :exchanger
end
end
RSpec.describe Exchanger do
context 'class hierarchy' do
if Concurrent.on_jruby?
it 'inherits from JavaExchanger' do
expect(Exchanger.ancestors).to include(JavaExchanger)
end
else
it 'inherits from RubyExchanger' do
expect(Exchanger.ancestors).to include(RubyExchanger)
end
end
end
end
end
|
