compute: Migrate compute service simulator to OpenTelemetry

This change updates the compute service simulator to use OpenTelemetry
for reporting metrics of the (simulated) hosts as opposed to using
custom event flows.

This approach is more generic, flexible and possibly offers better
performance as we can collect metrics of all services in a single sweep,
as opposed to listening to several services and each invoking the
handlers.

2 files changed, 0 insertions, 78 deletions

diff --git a/simulator/opendc-compute/opendc-compute-service/src/main/kotlin/org/opendc/compute/service/driver/Host.kt b/simulator/opendc-compute/opendc-compute-service/src/main/kotlin/org/opendc/compute/service/driver/Host.kt
index c3c39572..bed15dfd 100644
--- a/simulator/opendc-compute/opendc-compute-service/src/main/kotlin/org/opendc/compute/service/driver/Host.kt
+++ b/simulator/opendc-compute/opendc-compute-service/src/main/kotlin/org/opendc/compute/service/driver/Host.kt
@@ -22,7 +22,6 @@
 
 package org.opendc.compute.service.driver
 
-import kotlinx.coroutines.flow.Flow
 import org.opendc.compute.api.Server
 import java.util.*
 
@@ -56,11 +55,6 @@ public interface Host {
     public val meta: Map<String, Any>
 
     /**
-     * The events emitted by the driver.
-     */
-    public val events: Flow<HostEvent>
-
-    /**
      * Determine whether the specified [instance][server] can still fit on this host.
      */
     public fun canFit(server: Server): Boolean
diff --git a/simulator/opendc-compute/opendc-compute-service/src/main/kotlin/org/opendc/compute/service/driver/HostEvent.kt b/simulator/opendc-compute/opendc-compute-service/src/main/kotlin/org/opendc/compute/service/driver/HostEvent.kt
deleted file mode 100644
index 97350679..00000000
--- a/simulator/opendc-compute/opendc-compute-service/src/main/kotlin/org/opendc/compute/service/driver/HostEvent.kt
+++ /dev/null
@@ -1,72 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.compute.service.driver
-
-/**
- * An event that is emitted by a [Host].
- */
-public sealed class HostEvent {
-    /**
-     * The driver that emitted the event.
-     */
-    public abstract val driver: Host
-
-    /**
-     * This event is emitted when the number of active servers on the server managed by this driver is updated.
-     *
-     * @property driver The driver that emitted the event.
-     * @property numberOfActiveServers The number of active servers.
-     * @property availableMemory The available memory, in MB.
-     */
-    public data class VmsUpdated(
-        override val driver: Host,
-        public val numberOfActiveServers: Int,
-        public val availableMemory: Long
-    ) : HostEvent()
-
-    /**
-     * This event is emitted when a slice is finished.
-     *
-     * @property driver The driver that emitted the event.
-     * @property requestedBurst The total requested CPU time (can be above capacity).
-     * @property grantedBurst The actual total granted capacity, which might be lower than the requested burst due to
-     * the hypervisor being interrupted during a slice.
-     * @property overcommissionedBurst The CPU time that the hypervisor could not grant to the virtual machine since
-     * it did not have the capacity.
-     * @property interferedBurst The sum of CPU time that virtual machines could not utilize due to performance
-     * interference.
-     * @property cpuUsage CPU use in megahertz.
-     * @property cpuDemand CPU demand in megahertz.
-     * @property numberOfDeployedImages The number of images deployed on this hypervisor.
-     */
-    public data class SliceFinished(
-        override val driver: Host,
-        public val requestedBurst: Long,
-        public val grantedBurst: Long,
-        public val overcommissionedBurst: Long,
-        public val interferedBurst: Long,
-        public val cpuUsage: Double,
-        public val cpuDemand: Double,
-        public val numberOfDeployedImages: Int,
-    ) : HostEvent()
-}