compute: Implement filter scheduler

This change adds an implementation of the filter scheduler to the OpenDC
Compute module. This is modeled after the filter scheduler
implementation in OpenStack and should allow for more flexible
scheduling policies.

See: https://docs.openstack.org/nova/latest/user/filter-scheduler.html

2 files changed, 16 insertions, 8 deletions

diff --git a/simulator/opendc-compute/opendc-compute-service/src/test/kotlin/org/opendc/compute/service/ComputeServiceTest.kt b/simulator/opendc-compute/opendc-compute-service/src/test/kotlin/org/opendc/compute/service/ComputeServiceTest.kt
index 45a306aa..c6e24346 100644
--- a/simulator/opendc-compute/opendc-compute-service/src/test/kotlin/org/opendc/compute/service/ComputeServiceTest.kt
+++ b/simulator/opendc-compute/opendc-compute-service/src/test/kotlin/org/opendc/compute/service/ComputeServiceTest.kt
@@ -39,7 +39,10 @@ import org.opendc.compute.service.driver.Host
 import org.opendc.compute.service.driver.HostListener
 import org.opendc.compute.service.driver.HostModel
 import org.opendc.compute.service.driver.HostState
-import org.opendc.compute.service.scheduler.AvailableMemoryAllocationPolicy
+import org.opendc.compute.service.scheduler.FilterScheduler
+import org.opendc.compute.service.scheduler.filters.ComputeCapabilitiesFilter
+import org.opendc.compute.service.scheduler.filters.ComputeFilter
+import org.opendc.compute.service.scheduler.weights.MemoryWeigher
 import org.opendc.simulator.utils.DelayControllerClockAdapter
 import java.util.*
 
@@ -55,9 +58,12 @@ internal class ComputeServiceTest {
     fun setUp() {
         scope = TestCoroutineScope()
         val clock = DelayControllerClockAdapter(scope)
-        val policy = AvailableMemoryAllocationPolicy()
+        val computeScheduler = FilterScheduler(
+            filters = listOf(ComputeFilter(), ComputeCapabilitiesFilter()),
+            weighers = listOf(MemoryWeigher() to -1.0)
+        )
         val meter = MeterProvider.noop().get("opendc-compute")
-        service = ComputeService(scope.coroutineContext, clock, meter, policy)
+        service = ComputeService(scope.coroutineContext, clock, meter, computeScheduler)
     }
 
     @AfterEach
@@ -257,6 +263,7 @@ internal class ComputeServiceTest {
         server.start()
         delay(5 * 60 * 1000)
 
+        every { host.state } returns HostState.UP
         listeners.forEach { it.onStateChanged(host, HostState.UP) }
 
         delay(5 * 60 * 1000)
@@ -286,6 +293,7 @@ internal class ComputeServiceTest {
 
         delay(5 * 60 * 1000)
 
+        every { host.state } returns HostState.DOWN
         listeners.forEach { it.onStateChanged(host, HostState.DOWN) }
 
         server.start()
diff --git a/simulator/opendc-compute/opendc-compute-service/src/test/kotlin/org/opendc/compute/service/scheduler/AllocationPolicyTest.kt b/simulator/opendc-compute/opendc-compute-service/src/test/kotlin/org/opendc/compute/service/scheduler/AllocationPolicyTest.kt
index db377914..7227d225 100644
--- a/simulator/opendc-compute/opendc-compute-service/src/test/kotlin/org/opendc/compute/service/scheduler/AllocationPolicyTest.kt
+++ b/simulator/opendc-compute/opendc-compute-service/src/test/kotlin/org/opendc/compute/service/scheduler/AllocationPolicyTest.kt
@@ -100,9 +100,9 @@ internal class AllocationPolicyTest {
                 every { view.host.model.cpuCount } returns random.nextInt(1, 16)
                 every { view.host.model.memorySize } returns random.nextLong(1024, 1024 * 1024)
                 every { view.availableMemory } returns random.nextLong(0, view.host.model.memorySize)
-                every { view.numberOfActiveServers } returns random.nextInt(0, 6)
+                every { view.instanceCount } returns random.nextInt(0, 6)
                 every { view.provisionedCores } returns random.nextInt(0, view.host.model.cpuCount)
-                every { view.toString() } returns "HostView[$i,numberOfActiveServers=${view.numberOfActiveServers}]"
+                every { view.toString() } returns "HostView[$i,numberOfActiveServers=${view.instanceCount}]"
                 view
             }
 
@@ -132,7 +132,7 @@ internal class AllocationPolicyTest {
                 every { view.host.model.cpuCount } returns random.nextInt(1, 16)
                 every { view.host.model.memorySize } returns random.nextLong(1024, 1024 * 1024)
                 every { view.availableMemory } returns random.nextLong(0, view.host.model.memorySize)
-                every { view.numberOfActiveServers } returns random.nextInt(0, 6)
+                every { view.instanceCount } returns random.nextInt(0, 6)
                 every { view.provisionedCores } returns random.nextInt(0, view.host.model.cpuCount)
                 every { view.toString() } returns "HostView[$i,availableMemory=${view.availableMemory}]"
                 view
@@ -164,7 +164,7 @@ internal class AllocationPolicyTest {
                 every { view.host.model.cpuCount } returns random.nextInt(1, 16)
                 every { view.host.model.memorySize } returns random.nextLong(1024, 1024 * 1024)
                 every { view.availableMemory } returns random.nextLong(0, view.host.model.memorySize)
-                every { view.numberOfActiveServers } returns random.nextInt(0, 6)
+                every { view.instanceCount } returns random.nextInt(0, 6)
                 every { view.provisionedCores } returns random.nextInt(0, view.host.model.cpuCount)
                 every { view.toString() } returns "HostView[$i,availableMemory=${view.availableMemory}]"
                 view
@@ -196,7 +196,7 @@ internal class AllocationPolicyTest {
                 every { view.host.model.cpuCount } returns random.nextInt(1, 16)
                 every { view.host.model.memorySize } returns random.nextLong(1024, 1024 * 1024)
                 every { view.availableMemory } returns random.nextLong(0, view.host.model.memorySize)
-                every { view.numberOfActiveServers } returns random.nextInt(0, 6)
+                every { view.instanceCount } returns random.nextInt(0, 6)
                 every { view.provisionedCores } returns random.nextInt(0, view.host.model.cpuCount)
                 every { view.toString() } returns "HostView[$i,provisionedCores=${view.provisionedCores}]"
                 view