func chooseStrategy(generator writestrategies.MessageGenerator, writer writestrategies.MessageWriter, writeRate int, burstDelay time.Duration) experiment.WriteStrategy {
if burstDelay > 0 {
params := writestrategies.BurstParameters{
Minimum: writeRate,
Maximum: writeRate,
Frequency: burstDelay,
}
return writestrategies.NewBurstWriteStrategy(generator, writer, params)
}
return writestrategies.NewConstantWriteStrategy(generator, writer, writeRate)
}
var (
writer mockWriter
stopChan chan struct{}
writeStrategy *writestrategies.BurstWriteStrategy
params writestrategies.BurstParameters
)
BeforeEach(func() {
writer = mockWriter{}
stopChan = make(chan struct{})
params = writestrategies.BurstParameters{
Minimum: 10,
Maximum: 100,
Frequency: 900 * time.Millisecond,
}
writeStrategy = writestrategies.NewBurstWriteStrategy(&mockGenerator{}, &writer, params)
})
It("writes messages in bursts", func() {
go writeStrategy.StartWriter(stopChan)
defer close(stopChan)
writes := func() uint32 {
return atomic.LoadUint32(&writer.count)
}
Eventually(writes).Should(BeNumerically(">=", params.Minimum))
Eventually(writes).Should(BeNumerically("<=", params.Maximum))
})
It("stops writing after the stoChan is closed", func() {
go writeStrategy.StartWriter(stopChan)
reportResults(firehoseReader, metronStreamWriter.Writes, b)
Expect(float64(firehoseReader.MetronSentMessageCount)).To(BeNumerically(">", writeRatePerSecond))
}, 1)
Measure("dropsonde metrics being passed from metron to the firehose nozzle in burst sequence", func(b Benchmarker) {
metronStreamWriter := endtoend.NewMetronStreamWriter()
firehoseReader := endtoend.NewFirehoseReader()
params := writestrategies.BurstParameters{
Minimum: 10,
Maximum: 100,
Frequency: time.Second,
}
generator := messagegenerator.NewValueMetricGenerator()
writeStrategy := writestrategies.NewBurstWriteStrategy(generator, metronStreamWriter, params)
ex := experiment.NewExperiment(firehoseReader)
ex.AddWriteStrategy(writeStrategy)
ex.Warmup()
go stopExperimentAfterTimeout(ex)
b.Time("runtime", func() {
ex.Start()
})
reportResults(firehoseReader, metronStreamWriter.Writes, b)
}, 1)
}
Context("Metron UDP, Doppler UDP", func() {