diff options
Diffstat (limited to 'opendc-compute/opendc-compute-simulator/src')
2 files changed, 24 insertions, 4 deletions
diff --git a/opendc-compute/opendc-compute-simulator/src/main/kotlin/org/opendc/compute/simulator/failure/StochasticVictimSelector.kt b/opendc-compute/opendc-compute-simulator/src/main/kotlin/org/opendc/compute/simulator/failure/StochasticVictimSelector.kt index b6d466bd..4aba0e91 100644 --- a/opendc-compute/opendc-compute-simulator/src/main/kotlin/org/opendc/compute/simulator/failure/StochasticVictimSelector.kt +++ b/opendc-compute/opendc-compute-simulator/src/main/kotlin/org/opendc/compute/simulator/failure/StochasticVictimSelector.kt @@ -24,7 +24,9 @@ package org.opendc.compute.simulator.failure import org.apache.commons.math3.distribution.RealDistribution import org.opendc.compute.simulator.SimHost -import java.util.Random +import java.util.ArrayList +import java.util.SplittableRandom +import java.util.random.RandomGenerator import kotlin.math.roundToInt /** @@ -32,12 +34,30 @@ import kotlin.math.roundToInt */ public class StochasticVictimSelector( private val size: RealDistribution, - private val random: Random = Random(0) + private val random: RandomGenerator = SplittableRandom(0) ) : VictimSelector { override fun select(hosts: Set<SimHost>): List<SimHost> { val n = size.sample().roundToInt() - return hosts.shuffled(random).take(n) + val result = ArrayList<SimHost>(n) + + val random = random + var samplesNeeded = n + var remainingHosts = hosts.size + val iterator = hosts.iterator() + + while (iterator.hasNext() && samplesNeeded > 0) { + val host = iterator.next() + + if (random.nextInt(remainingHosts) < samplesNeeded) { + result.add(host) + samplesNeeded-- + } + + remainingHosts-- + } + + return result } override fun toString(): String = "StochasticVictimSelector[$size]" diff --git a/opendc-compute/opendc-compute-simulator/src/test/kotlin/org/opendc/compute/simulator/failure/HostFaultInjectorTest.kt b/opendc-compute/opendc-compute-simulator/src/test/kotlin/org/opendc/compute/simulator/failure/HostFaultInjectorTest.kt index 90f534e6..a65c37cf 100644 --- a/opendc-compute/opendc-compute-simulator/src/test/kotlin/org/opendc/compute/simulator/failure/HostFaultInjectorTest.kt +++ b/opendc-compute/opendc-compute-simulator/src/test/kotlin/org/opendc/compute/simulator/failure/HostFaultInjectorTest.kt @@ -38,7 +38,7 @@ import kotlin.math.ln /** * Test suite for [HostFaultInjector] class. */ -internal class HostFaultInjectorTest { +class HostFaultInjectorTest { /** * Simple test case to test that nothing happens when the injector is not started. */ |