merge: Add support for SQL via Apache Calcite (#78)

This pull request integrates initial support for SQL queries via Apache Calcite into the OpenDC codebase. 
Our vision is that users of OpenDC should be able to use SQL queries to access and process most 
of the experiment data generated by simulations.

This pull request moves towards this goal by adding the ability to query workload traces supported 
by OpenDC using SQL. We also provide a CLI for querying the data in workload traces via `opendc-trace-tools`:

```bash
opendc-trace-tools query -i data/bitbrains-small  -f opendc-vm "SELECT MAX(cpu_count) FROM resource_states"
```

## Implementation Notes :hammer_and_pick:

* Add Calcite (SQL) integration
* Add support for writing via SQL 
* Add support for writing via SQL 
* Support custom Parquet ReadSupport implementations
* Read records using low-level Parquet API 
* Do not use Avro when exporting experiment data
* Do not use Avro when reading WTF trace
* Drop dependency on Avro
* Add support for projections

## External Dependencies :four_leaf_clover:

* Apache Calcite

## Breaking API Changes :warning:

* The existing code for reading Parquet traces using Apache Avro has been removed.
* `TraceFormat.newReader` now accepts a nullable `projection` parameter 

9 files changed, 675 insertions, 147 deletions

diff --git a/opendc-compute/opendc-compute-workload/build.gradle.kts b/opendc-compute/opendc-compute-workload/build.gradle.kts
index 9ced95a7..319b2ae3 100644
--- a/opendc-compute/opendc-compute-workload/build.gradle.kts
+++ b/opendc-compute/opendc-compute-workload/build.gradle.kts
@@ -39,4 +39,6 @@ dependencies {
     implementation(libs.opentelemetry.semconv)
 
     implementation(libs.kotlin.logging)
+
+    testImplementation(libs.slf4j.simple)
 }
diff --git a/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetDataWriter.kt b/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetDataWriter.kt
index 84387bbc..c854d874 100644
--- a/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetDataWriter.kt
+++ b/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetDataWriter.kt
@@ -23,14 +23,12 @@
 package org.opendc.compute.workload.export.parquet
 
 import mu.KotlinLogging
-import org.apache.avro.Schema
-import org.apache.avro.generic.GenericData
-import org.apache.avro.generic.GenericRecordBuilder
-import org.apache.parquet.avro.AvroParquetWriter
+import org.apache.parquet.column.ParquetProperties
 import org.apache.parquet.hadoop.ParquetFileWriter
 import org.apache.parquet.hadoop.ParquetWriter
+import org.apache.parquet.hadoop.api.WriteSupport
 import org.apache.parquet.hadoop.metadata.CompressionCodecName
-import org.opendc.trace.util.parquet.LocalOutputFile
+import org.opendc.trace.util.parquet.LocalParquetWriter
 import java.io.File
 import java.util.concurrent.ArrayBlockingQueue
 import java.util.concurrent.BlockingQueue
@@ -38,10 +36,13 @@ import kotlin.concurrent.thread
 
 /**
  * A writer that writes data in Parquet format.
+ *
+ * @param path The path to the file to write the data to.
+ * @param writeSupport The [WriteSupport] implementation for converting the records to Parquet format.
  */
 public abstract class ParquetDataWriter<in T>(
     path: File,
-    private val schema: Schema,
+    private val writeSupport: WriteSupport<T>,
     bufferSize: Int = 4096
 ) : AutoCloseable {
     /**
@@ -52,7 +53,7 @@ public abstract class ParquetDataWriter<in T>(
     /**
      * The queue of records to process.
      */
-    private val queue: BlockingQueue<GenericData.Record> = ArrayBlockingQueue(bufferSize)
+    private val queue: BlockingQueue<T> = ArrayBlockingQueue(bufferSize)
 
     /**
      * An exception to be propagated to the actual writer.
@@ -64,15 +65,15 @@ public abstract class ParquetDataWriter<in T>(
      */
     private val writerThread = thread(start = false, name = this.toString()) {
         val writer = let {
-            val builder = AvroParquetWriter.builder<GenericData.Record>(LocalOutputFile(path))
-                .withSchema(schema)
+            val builder = LocalParquetWriter.builder(path.toPath(), writeSupport)
+                .withWriterVersion(ParquetProperties.WriterVersion.PARQUET_2_0)
                 .withCompressionCodec(CompressionCodecName.ZSTD)
                 .withWriteMode(ParquetFileWriter.Mode.OVERWRITE)
             buildWriter(builder)
         }
 
         val queue = queue
-        val buf = mutableListOf<GenericData.Record>()
+        val buf = mutableListOf<T>()
         var shouldStop = false
 
         try {
@@ -101,16 +102,11 @@ public abstract class ParquetDataWriter<in T>(
     /**
      * Build the [ParquetWriter] used to write the Parquet files.
      */
-    protected open fun buildWriter(builder: AvroParquetWriter.Builder<GenericData.Record>): ParquetWriter<GenericData.Record> {
+    protected open fun buildWriter(builder: LocalParquetWriter.Builder<@UnsafeVariance T>): ParquetWriter<@UnsafeVariance T> {
         return builder.build()
     }
 
     /**
-     * Convert the specified [data] into a Parquet record.
-     */
-    protected abstract fun convert(builder: GenericRecordBuilder, data: T)
-
-    /**
      * Write the specified metrics to the database.
      */
     public fun write(data: T) {
@@ -119,9 +115,7 @@ public abstract class ParquetDataWriter<in T>(
             throw IllegalStateException("Writer thread failed", exception)
         }
 
-        val builder = GenericRecordBuilder(schema)
-        convert(builder, data)
-        queue.put(builder.build())
+        queue.put(data)
     }
 
     /**
diff --git a/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetHostDataWriter.kt b/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetHostDataWriter.kt
index 2b7cac8f..0d5b6b34 100644
--- a/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetHostDataWriter.kt
+++ b/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetHostDataWriter.kt
@@ -22,81 +22,189 @@
 
 package org.opendc.compute.workload.export.parquet
 
-import org.apache.avro.Schema
-import org.apache.avro.SchemaBuilder
-import org.apache.avro.generic.GenericData
-import org.apache.avro.generic.GenericRecordBuilder
-import org.apache.parquet.avro.AvroParquetWriter
+import org.apache.hadoop.conf.Configuration
 import org.apache.parquet.hadoop.ParquetWriter
+import org.apache.parquet.hadoop.api.WriteSupport
+import org.apache.parquet.io.api.RecordConsumer
+import org.apache.parquet.schema.*
 import org.opendc.telemetry.compute.table.HostTableReader
-import org.opendc.trace.util.parquet.TIMESTAMP_SCHEMA
-import org.opendc.trace.util.parquet.UUID_SCHEMA
-import org.opendc.trace.util.parquet.optional
+import org.opendc.trace.util.parquet.LocalParquetWriter
 import java.io.File
+import java.util.*
 
 /**
  * A Parquet event writer for [HostTableReader]s.
  */
 public class ParquetHostDataWriter(path: File, bufferSize: Int) :
-    ParquetDataWriter<HostTableReader>(path, SCHEMA, bufferSize) {
+    ParquetDataWriter<HostTableReader>(path, HostDataWriteSupport(), bufferSize) {
 
-    override fun buildWriter(builder: AvroParquetWriter.Builder<GenericData.Record>): ParquetWriter<GenericData.Record> {
+    override fun buildWriter(builder: LocalParquetWriter.Builder<HostTableReader>): ParquetWriter<HostTableReader> {
         return builder
             .withDictionaryEncoding("host_id", true)
             .build()
     }
 
-    override fun convert(builder: GenericRecordBuilder, data: HostTableReader) {
-        builder["timestamp"] = data.timestamp.toEpochMilli()
+    override fun toString(): String = "host-writer"
 
-        builder["host_id"] = data.host.id
+    /**
+     * A [WriteSupport] implementation for a [HostTableReader].
+     */
+    private class HostDataWriteSupport : WriteSupport<HostTableReader>() {
+        lateinit var recordConsumer: RecordConsumer
 
-        builder["uptime"] = data.uptime
-        builder["downtime"] = data.downtime
-        val bootTime = data.bootTime
-        builder["boot_time"] = bootTime?.toEpochMilli()
+        override fun init(configuration: Configuration): WriteContext {
+            return WriteContext(SCHEMA, emptyMap())
+        }
 
-        builder["cpu_count"] = data.host.cpuCount
-        builder["cpu_limit"] = data.cpuLimit
-        builder["cpu_time_active"] = data.cpuActiveTime
-        builder["cpu_time_idle"] = data.cpuIdleTime
-        builder["cpu_time_steal"] = data.cpuStealTime
-        builder["cpu_time_lost"] = data.cpuLostTime
+        override fun prepareForWrite(recordConsumer: RecordConsumer) {
+            this.recordConsumer = recordConsumer
+        }
 
-        builder["mem_limit"] = data.host.memCapacity
+        override fun write(record: HostTableReader) {
+            write(recordConsumer, record)
+        }
 
-        builder["power_total"] = data.powerTotal
+        private fun write(consumer: RecordConsumer, data: HostTableReader) {
+            consumer.startMessage()
 
-        builder["guests_terminated"] = data.guestsTerminated
-        builder["guests_running"] = data.guestsRunning
-        builder["guests_error"] = data.guestsError
-        builder["guests_invalid"] = data.guestsInvalid
-    }
+            consumer.startField("timestamp", 0)
+            consumer.addLong(data.timestamp.toEpochMilli())
+            consumer.endField("timestamp", 0)
 
-    override fun toString(): String = "host-writer"
+            consumer.startField("host_id", 1)
+            consumer.addBinary(UUID.fromString(data.host.id).toBinary())
+            consumer.endField("host_id", 1)
+
+            consumer.startField("uptime", 2)
+            consumer.addLong(data.uptime)
+            consumer.endField("uptime", 2)
+
+            consumer.startField("downtime", 3)
+            consumer.addLong(data.downtime)
+            consumer.endField("downtime", 3)
+
+            val bootTime = data.bootTime
+            if (bootTime != null) {
+                consumer.startField("boot_time", 4)
+                consumer.addLong(bootTime.toEpochMilli())
+                consumer.endField("boot_time", 4)
+            }
+
+            consumer.startField("cpu_count", 5)
+            consumer.addInteger(data.host.cpuCount)
+            consumer.endField("cpu_count", 5)
+
+            consumer.startField("cpu_limit", 6)
+            consumer.addDouble(data.cpuLimit)
+            consumer.endField("cpu_limit", 6)
+
+            consumer.startField("cpu_time_active", 7)
+            consumer.addLong(data.cpuActiveTime)
+            consumer.endField("cpu_time_active", 7)
+
+            consumer.startField("cpu_time_idle", 8)
+            consumer.addLong(data.cpuIdleTime)
+            consumer.endField("cpu_time_idle", 8)
+
+            consumer.startField("cpu_time_steal", 9)
+            consumer.addLong(data.cpuStealTime)
+            consumer.endField("cpu_time_steal", 9)
+
+            consumer.startField("cpu_time_lost", 10)
+            consumer.addLong(data.cpuLostTime)
+            consumer.endField("cpu_time_lost", 10)
+
+            consumer.startField("mem_limit", 11)
+            consumer.addLong(data.host.memCapacity)
+            consumer.endField("mem_limit", 11)
+
+            consumer.startField("power_total", 12)
+            consumer.addDouble(data.powerTotal)
+            consumer.endField("power_total", 12)
+
+            consumer.startField("guests_terminated", 13)
+            consumer.addInteger(data.guestsTerminated)
+            consumer.endField("guests_terminated", 13)
+
+            consumer.startField("guests_running", 14)
+            consumer.addInteger(data.guestsRunning)
+            consumer.endField("guests_running", 14)
+
+            consumer.startField("guests_error", 15)
+            consumer.addInteger(data.guestsError)
+            consumer.endField("guests_error", 15)
+
+            consumer.startField("guests_invalid", 16)
+            consumer.addInteger(data.guestsInvalid)
+            consumer.endField("guests_invalid", 16)
+
+            consumer.endMessage()
+        }
+    }
 
     private companion object {
-        private val SCHEMA: Schema = SchemaBuilder
-            .record("host")
-            .namespace("org.opendc.telemetry.compute")
-            .fields()
-            .name("timestamp").type(TIMESTAMP_SCHEMA).noDefault()
-            .name("host_id").type(UUID_SCHEMA).noDefault()
-            .requiredLong("uptime")
-            .requiredLong("downtime")
-            .name("boot_time").type(TIMESTAMP_SCHEMA.optional()).noDefault()
-            .requiredInt("cpu_count")
-            .requiredDouble("cpu_limit")
-            .requiredLong("cpu_time_active")
-            .requiredLong("cpu_time_idle")
-            .requiredLong("cpu_time_steal")
-            .requiredLong("cpu_time_lost")
-            .requiredLong("mem_limit")
-            .requiredDouble("power_total")
-            .requiredInt("guests_terminated")
-            .requiredInt("guests_running")
-            .requiredInt("guests_error")
-            .requiredInt("guests_invalid")
-            .endRecord()
+        /**
+         * The schema of the host data.
+         */
+        val SCHEMA: MessageType = Types
+            .buildMessage()
+            .addFields(
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .`as`(LogicalTypeAnnotation.timestampType(true, LogicalTypeAnnotation.TimeUnit.MILLIS))
+                    .named("timestamp"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.FIXED_LEN_BYTE_ARRAY)
+                    .length(16)
+                    .`as`(LogicalTypeAnnotation.uuidType())
+                    .named("host_id"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .named("uptime"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .named("downtime"),
+                Types
+                    .optional(PrimitiveType.PrimitiveTypeName.INT64)
+                    .`as`(LogicalTypeAnnotation.timestampType(true, LogicalTypeAnnotation.TimeUnit.MILLIS))
+                    .named("boot_time"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT32)
+                    .named("cpu_count"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.DOUBLE)
+                    .named("cpu_limit"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .named("cpu_time_active"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .named("cpu_time_idle"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .named("cpu_time_steal"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .named("cpu_time_lost"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .named("mem_limit"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.DOUBLE)
+                    .named("power_total"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT32)
+                    .named("guests_terminated"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT32)
+                    .named("guests_running"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT32)
+                    .named("guests_error"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT32)
+                    .named("guests_invalid"),
+            )
+            .named("host")
     }
 }
diff --git a/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetServerDataWriter.kt b/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetServerDataWriter.kt
index 144b6624..5d11629b 100644
--- a/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetServerDataWriter.kt
+++ b/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetServerDataWriter.kt
@@ -22,73 +22,177 @@
 
 package org.opendc.compute.workload.export.parquet
 
-import org.apache.avro.Schema
-import org.apache.avro.SchemaBuilder
-import org.apache.avro.generic.GenericData
-import org.apache.avro.generic.GenericRecordBuilder
-import org.apache.parquet.avro.AvroParquetWriter
+import org.apache.hadoop.conf.Configuration
 import org.apache.parquet.hadoop.ParquetWriter
+import org.apache.parquet.hadoop.api.WriteSupport
+import org.apache.parquet.io.api.RecordConsumer
+import org.apache.parquet.schema.*
 import org.opendc.telemetry.compute.table.ServerTableReader
-import org.opendc.trace.util.parquet.TIMESTAMP_SCHEMA
-import org.opendc.trace.util.parquet.UUID_SCHEMA
-import org.opendc.trace.util.parquet.optional
+import org.opendc.trace.util.parquet.LocalParquetWriter
 import java.io.File
+import java.util.*
 
 /**
  * A Parquet event writer for [ServerTableReader]s.
  */
 public class ParquetServerDataWriter(path: File, bufferSize: Int) :
-    ParquetDataWriter<ServerTableReader>(path, SCHEMA, bufferSize) {
+    ParquetDataWriter<ServerTableReader>(path, ServerDataWriteSupport(), bufferSize) {
 
-    override fun buildWriter(builder: AvroParquetWriter.Builder<GenericData.Record>): ParquetWriter<GenericData.Record> {
+    override fun buildWriter(builder: LocalParquetWriter.Builder<ServerTableReader>): ParquetWriter<ServerTableReader> {
         return builder
             .withDictionaryEncoding("server_id", true)
             .withDictionaryEncoding("host_id", true)
             .build()
     }
 
-    override fun convert(builder: GenericRecordBuilder, data: ServerTableReader) {
-        builder["timestamp"] = data.timestamp.toEpochMilli()
+    override fun toString(): String = "server-writer"
 
-        builder["server_id"] = data.server.id
-        builder["host_id"] = data.host?.id
+    /**
+     * A [WriteSupport] implementation for a [ServerTableReader].
+     */
+    private class ServerDataWriteSupport : WriteSupport<ServerTableReader>() {
+        lateinit var recordConsumer: RecordConsumer
 
-        builder["uptime"] = data.uptime
-        builder["downtime"] = data.downtime
-        builder["boot_time"] = data.bootTime?.toEpochMilli()
-        builder["provision_time"] = data.provisionTime?.toEpochMilli()
+        override fun init(configuration: Configuration): WriteContext {
+            return WriteContext(SCHEMA, emptyMap())
+        }
 
-        builder["cpu_count"] = data.server.cpuCount
-        builder["cpu_limit"] = data.cpuLimit
-        builder["cpu_time_active"] = data.cpuActiveTime
-        builder["cpu_time_idle"] = data.cpuIdleTime
-        builder["cpu_time_steal"] = data.cpuStealTime
-        builder["cpu_time_lost"] = data.cpuLostTime
+        override fun prepareForWrite(recordConsumer: RecordConsumer) {
+            this.recordConsumer = recordConsumer
+        }
 
-        builder["mem_limit"] = data.server.memCapacity
-    }
+        override fun write(record: ServerTableReader) {
+            write(recordConsumer, record)
+        }
 
-    override fun toString(): String = "server-writer"
+        private fun write(consumer: RecordConsumer, data: ServerTableReader) {
+            consumer.startMessage()
+
+            consumer.startField("timestamp", 0)
+            consumer.addLong(data.timestamp.toEpochMilli())
+            consumer.endField("timestamp", 0)
+
+            consumer.startField("server_id", 1)
+            consumer.addBinary(UUID.fromString(data.server.id).toBinary())
+            consumer.endField("server_id", 1)
+
+            val hostId = data.host?.id
+            if (hostId != null) {
+                consumer.startField("host_id", 2)
+                consumer.addBinary(UUID.fromString(hostId).toBinary())
+                consumer.endField("host_id", 2)
+            }
+
+            consumer.startField("uptime", 3)
+            consumer.addLong(data.uptime)
+            consumer.endField("uptime", 3)
+
+            consumer.startField("downtime", 4)
+            consumer.addLong(data.downtime)
+            consumer.endField("downtime", 4)
+
+            val bootTime = data.bootTime
+            if (bootTime != null) {
+                consumer.startField("boot_time", 5)
+                consumer.addLong(bootTime.toEpochMilli())
+                consumer.endField("boot_time", 5)
+            }
+
+            val provisionTime = data.provisionTime
+            if (provisionTime != null) {
+                consumer.startField("provision_time", 6)
+                consumer.addLong(provisionTime.toEpochMilli())
+                consumer.endField("provision_time", 6)
+            }
+
+            consumer.startField("cpu_count", 7)
+            consumer.addInteger(data.server.cpuCount)
+            consumer.endField("cpu_count", 7)
+
+            consumer.startField("cpu_limit", 8)
+            consumer.addDouble(data.cpuLimit)
+            consumer.endField("cpu_limit", 8)
+
+            consumer.startField("cpu_time_active", 9)
+            consumer.addLong(data.cpuActiveTime)
+            consumer.endField("cpu_time_active", 9)
+
+            consumer.startField("cpu_time_idle", 10)
+            consumer.addLong(data.cpuIdleTime)
+            consumer.endField("cpu_time_idle", 10)
+
+            consumer.startField("cpu_time_steal", 11)
+            consumer.addLong(data.cpuStealTime)
+            consumer.endField("cpu_time_steal", 11)
+
+            consumer.startField("cpu_time_lost", 12)
+            consumer.addLong(data.cpuLostTime)
+            consumer.endField("cpu_time_lost", 12)
+
+            consumer.startField("mem_limit", 13)
+            consumer.addLong(data.server.memCapacity)
+            consumer.endField("mem_limit", 13)
+
+            consumer.endMessage()
+        }
+    }
 
     private companion object {
-        private val SCHEMA: Schema = SchemaBuilder
-            .record("server")
-            .namespace("org.opendc.telemetry.compute")
-            .fields()
-            .name("timestamp").type(TIMESTAMP_SCHEMA).noDefault()
-            .name("server_id").type(UUID_SCHEMA).noDefault()
-            .name("host_id").type(UUID_SCHEMA.optional()).noDefault()
-            .requiredLong("uptime")
-            .requiredLong("downtime")
-            .name("provision_time").type(TIMESTAMP_SCHEMA.optional()).noDefault()
-            .name("boot_time").type(TIMESTAMP_SCHEMA.optional()).noDefault()
-            .requiredInt("cpu_count")
-            .requiredDouble("cpu_limit")
-            .requiredLong("cpu_time_active")
-            .requiredLong("cpu_time_idle")
-            .requiredLong("cpu_time_steal")
-            .requiredLong("cpu_time_lost")
-            .requiredLong("mem_limit")
-            .endRecord()
+        /**
+         * The schema of the server data.
+         */
+        val SCHEMA: MessageType = Types.buildMessage()
+            .addFields(
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .`as`(LogicalTypeAnnotation.timestampType(true, LogicalTypeAnnotation.TimeUnit.MILLIS))
+                    .named("timestamp"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.FIXED_LEN_BYTE_ARRAY)
+                    .length(16)
+                    .`as`(LogicalTypeAnnotation.uuidType())
+                    .named("server_id"),
+                Types
+                    .optional(PrimitiveType.PrimitiveTypeName.FIXED_LEN_BYTE_ARRAY)
+                    .length(16)
+                    .`as`(LogicalTypeAnnotation.uuidType())
+                    .named("host_id"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .named("uptime"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .named("downtime"),
+                Types
+                    .optional(PrimitiveType.PrimitiveTypeName.INT64)
+                    .`as`(LogicalTypeAnnotation.timestampType(true, LogicalTypeAnnotation.TimeUnit.MILLIS))
+                    .named("provision_time"),
+                Types
+                    .optional(PrimitiveType.PrimitiveTypeName.INT64)
+                    .`as`(LogicalTypeAnnotation.timestampType(true, LogicalTypeAnnotation.TimeUnit.MILLIS))
+                    .named("boot_time"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT32)
+                    .named("cpu_count"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.DOUBLE)
+                    .named("cpu_limit"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .named("cpu_time_active"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .named("cpu_time_idle"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .named("cpu_time_steal"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .named("cpu_time_lost"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .named("mem_limit")
+            )
+            .named("server")
     }
 }
diff --git a/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetServiceDataWriter.kt b/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetServiceDataWriter.kt
index ec8a2b65..5ad3b95e 100644
--- a/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetServiceDataWriter.kt
+++ b/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/ParquetServiceDataWriter.kt
@@ -22,45 +22,108 @@
 
 package org.opendc.compute.workload.export.parquet
 
-import org.apache.avro.Schema
-import org.apache.avro.SchemaBuilder
-import org.apache.avro.generic.GenericRecordBuilder
+import io.opentelemetry.context.ContextKey.named
+import org.apache.hadoop.conf.Configuration
+import org.apache.parquet.hadoop.api.WriteSupport
+import org.apache.parquet.io.api.RecordConsumer
+import org.apache.parquet.schema.*
 import org.opendc.telemetry.compute.table.ServiceTableReader
-import org.opendc.trace.util.parquet.TIMESTAMP_SCHEMA
 import java.io.File
 
 /**
  * A Parquet event writer for [ServiceTableReader]s.
  */
 public class ParquetServiceDataWriter(path: File, bufferSize: Int) :
-    ParquetDataWriter<ServiceTableReader>(path, SCHEMA, bufferSize) {
-
-    override fun convert(builder: GenericRecordBuilder, data: ServiceTableReader) {
-        builder["timestamp"] = data.timestamp.toEpochMilli()
-        builder["hosts_up"] = data.hostsUp
-        builder["hosts_down"] = data.hostsDown
-        builder["servers_pending"] = data.serversPending
-        builder["servers_active"] = data.serversActive
-        builder["attempts_success"] = data.attemptsSuccess
-        builder["attempts_failure"] = data.attemptsFailure
-        builder["attempts_error"] = data.attemptsError
-    }
+    ParquetDataWriter<ServiceTableReader>(path, ServiceDataWriteSupport(), bufferSize) {
 
     override fun toString(): String = "service-writer"
 
+    /**
+     * A [WriteSupport] implementation for a [ServiceTableReader].
+     */
+    private class ServiceDataWriteSupport : WriteSupport<ServiceTableReader>() {
+        lateinit var recordConsumer: RecordConsumer
+
+        override fun init(configuration: Configuration): WriteContext {
+            return WriteContext(SCHEMA, emptyMap())
+        }
+
+        override fun prepareForWrite(recordConsumer: RecordConsumer) {
+            this.recordConsumer = recordConsumer
+        }
+
+        override fun write(record: ServiceTableReader) {
+            write(recordConsumer, record)
+        }
+
+        private fun write(consumer: RecordConsumer, data: ServiceTableReader) {
+            consumer.startMessage()
+
+            consumer.startField("timestamp", 0)
+            consumer.addLong(data.timestamp.toEpochMilli())
+            consumer.endField("timestamp", 0)
+
+            consumer.startField("hosts_up", 1)
+            consumer.addInteger(data.hostsUp)
+            consumer.endField("hosts_up", 1)
+
+            consumer.startField("hosts_down", 2)
+            consumer.addInteger(data.hostsDown)
+            consumer.endField("hosts_down", 2)
+
+            consumer.startField("servers_pending", 3)
+            consumer.addInteger(data.serversPending)
+            consumer.endField("servers_pending", 3)
+
+            consumer.startField("servers_active", 4)
+            consumer.addInteger(data.serversActive)
+            consumer.endField("servers_active", 4)
+
+            consumer.startField("attempts_success", 5)
+            consumer.addInteger(data.attemptsSuccess)
+            consumer.endField("attempts_pending", 5)
+
+            consumer.startField("attempts_failure", 6)
+            consumer.addInteger(data.attemptsFailure)
+            consumer.endField("attempts_failure", 6)
+
+            consumer.startField("attempts_error", 7)
+            consumer.addInteger(data.attemptsError)
+            consumer.endField("attempts_error", 7)
+
+            consumer.endMessage()
+        }
+    }
+
     private companion object {
-        private val SCHEMA: Schema = SchemaBuilder
-            .record("service")
-            .namespace("org.opendc.telemetry.compute")
-            .fields()
-            .name("timestamp").type(TIMESTAMP_SCHEMA).noDefault()
-            .requiredInt("hosts_up")
-            .requiredInt("hosts_down")
-            .requiredInt("servers_pending")
-            .requiredInt("servers_active")
-            .requiredInt("attempts_success")
-            .requiredInt("attempts_failure")
-            .requiredInt("attempts_error")
-            .endRecord()
+        private val SCHEMA: MessageType = Types.buildMessage()
+            .addFields(
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT64)
+                    .`as`(LogicalTypeAnnotation.timestampType(true, LogicalTypeAnnotation.TimeUnit.MILLIS))
+                    .named("timestamp"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT32)
+                    .named("hosts_up"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT32)
+                    .named("hosts_down"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT32)
+                    .named("servers_pending"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT32)
+                    .named("servers_active"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT32)
+                    .named("attempts_success"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT32)
+                    .named("attempts_failure"),
+                Types
+                    .required(PrimitiveType.PrimitiveTypeName.INT32)
+                    .named("attempts_error"),
+            )
+            .named("service")
     }
 }
diff --git a/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/Utils.kt b/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/Utils.kt
new file mode 100644
index 00000000..9921f5b8
--- /dev/null
+++ b/opendc-compute/opendc-compute-workload/src/main/kotlin/org/opendc/compute/workload/export/parquet/Utils.kt
@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2022 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.workload.export.parquet
+
+import org.apache.parquet.io.api.Binary
+import java.nio.ByteBuffer
+import java.util.UUID
+
+/**
+ *
+ * @author Fabian Mastenbroek (f.s.mastenbroek@student.tudelft.nl)
+ */
+internal fun UUID.toBinary(): Binary {
+    val bb = ByteBuffer.wrap(ByteArray(16))
+    bb.putLong(mostSignificantBits)
+    bb.putLong(leastSignificantBits)
+    return Binary.fromConstantByteBuffer(bb)
+}
diff --git a/opendc-compute/opendc-compute-workload/src/test/kotlin/org/opendc/compute/workload/export/parquet/HostDataWriterTest.kt b/opendc-compute/opendc-compute-workload/src/test/kotlin/org/opendc/compute/workload/export/parquet/HostDataWriterTest.kt
new file mode 100644
index 00000000..dae03513
--- /dev/null
+++ b/opendc-compute/opendc-compute-workload/src/test/kotlin/org/opendc/compute/workload/export/parquet/HostDataWriterTest.kt
@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2022 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.workload.export.parquet
+
+import org.junit.jupiter.api.AfterEach
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.assertDoesNotThrow
+import org.opendc.telemetry.compute.table.HostInfo
+import org.opendc.telemetry.compute.table.HostTableReader
+import java.nio.file.Files
+import java.time.Instant
+
+/**
+ * Test suite for [ParquetHostDataWriter]
+ */
+class HostDataWriterTest {
+    /**
+     * The path to write the data file to.
+     */
+    private val path = Files.createTempFile("opendc", "parquet")
+
+    /**
+     * The writer used to write the data.
+     */
+    private val writer = ParquetHostDataWriter(path.toFile(), bufferSize = 4096)
+
+    @AfterEach
+    fun tearDown() {
+        writer.close()
+        Files.deleteIfExists(path)
+    }
+
+    @Test
+    fun testSmoke() {
+        assertDoesNotThrow {
+            writer.write(object : HostTableReader {
+                override val timestamp: Instant = Instant.now()
+                override val host: HostInfo = HostInfo("id", "test", "x86", 4, 4096)
+                override val guestsTerminated: Int = 0
+                override val guestsRunning: Int = 0
+                override val guestsError: Int = 0
+                override val guestsInvalid: Int = 0
+                override val cpuLimit: Double = 4096.0
+                override val cpuUsage: Double = 1.0
+                override val cpuDemand: Double = 1.0
+                override val cpuUtilization: Double = 0.0
+                override val cpuActiveTime: Long = 1
+                override val cpuIdleTime: Long = 1
+                override val cpuStealTime: Long = 1
+                override val cpuLostTime: Long = 1
+                override val powerUsage: Double = 1.0
+                override val powerTotal: Double = 1.0
+                override val uptime: Long = 1
+                override val downtime: Long = 1
+                override val bootTime: Instant? = null
+            })
+        }
+    }
+}
diff --git a/opendc-compute/opendc-compute-workload/src/test/kotlin/org/opendc/compute/workload/export/parquet/ServerDataWriterTest.kt b/opendc-compute/opendc-compute-workload/src/test/kotlin/org/opendc/compute/workload/export/parquet/ServerDataWriterTest.kt
new file mode 100644
index 00000000..280f5ef8
--- /dev/null
+++ b/opendc-compute/opendc-compute-workload/src/test/kotlin/org/opendc/compute/workload/export/parquet/ServerDataWriterTest.kt
@@ -0,0 +1,73 @@
+/*
+ * Copyright (c) 2022 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.workload.export.parquet
+
+import org.junit.jupiter.api.AfterEach
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.assertDoesNotThrow
+import org.opendc.telemetry.compute.table.HostInfo
+import org.opendc.telemetry.compute.table.ServerInfo
+import org.opendc.telemetry.compute.table.ServerTableReader
+import java.nio.file.Files
+import java.time.Instant
+
+/**
+ * Test suite for [ParquetServerDataWriter]
+ */
+class ServerDataWriterTest {
+    /**
+     * The path to write the data file to.
+     */
+    private val path = Files.createTempFile("opendc", "parquet")
+
+    /**
+     * The writer used to write the data.
+     */
+    private val writer = ParquetServerDataWriter(path.toFile(), bufferSize = 4096)
+
+    @AfterEach
+    fun tearDown() {
+        writer.close()
+        Files.deleteIfExists(path)
+    }
+
+    @Test
+    fun testSmoke() {
+        assertDoesNotThrow {
+            writer.write(object : ServerTableReader {
+                override val timestamp: Instant = Instant.now()
+                override val server: ServerInfo = ServerInfo("id", "test", "vm", "x86", "test", "test", 2, 4096)
+                override val host: HostInfo = HostInfo("id", "test", "x86", 4, 4096)
+                override val cpuLimit: Double = 4096.0
+                override val cpuActiveTime: Long = 1
+                override val cpuIdleTime: Long = 1
+                override val cpuStealTime: Long = 1
+                override val cpuLostTime: Long = 1
+                override val uptime: Long = 1
+                override val downtime: Long = 1
+                override val provisionTime: Instant = timestamp
+                override val bootTime: Instant? = null
+            })
+        }
+    }
+}
diff --git a/opendc-compute/opendc-compute-workload/src/test/kotlin/org/opendc/compute/workload/export/parquet/ServiceDataWriterTest.kt b/opendc-compute/opendc-compute-workload/src/test/kotlin/org/opendc/compute/workload/export/parquet/ServiceDataWriterTest.kt
new file mode 100644
index 00000000..7ffa7186
--- /dev/null
+++ b/opendc-compute/opendc-compute-workload/src/test/kotlin/org/opendc/compute/workload/export/parquet/ServiceDataWriterTest.kt
@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2022 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.workload.export.parquet
+
+import org.junit.jupiter.api.AfterEach
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.assertDoesNotThrow
+import org.opendc.telemetry.compute.table.ServiceTableReader
+import java.nio.file.Files
+import java.time.Instant
+
+/**
+ * Test suite for [ParquetServiceDataWriter]
+ */
+class ServiceDataWriterTest {
+    /**
+     * The path to write the data file to.
+     */
+    private val path = Files.createTempFile("opendc", "parquet")
+
+    /**
+     * The writer used to write the data.
+     */
+    private val writer = ParquetServiceDataWriter(path.toFile(), bufferSize = 4096)
+
+    @AfterEach
+    fun tearDown() {
+        writer.close()
+        Files.deleteIfExists(path)
+    }
+
+    @Test
+    fun testSmoke() {
+        assertDoesNotThrow {
+            writer.write(object : ServiceTableReader {
+                override val timestamp: Instant = Instant.now()
+                override val hostsUp: Int = 1
+                override val hostsDown: Int = 0
+                override val serversPending: Int = 1
+                override val serversActive: Int = 1
+                override val attemptsSuccess: Int = 1
+                override val attemptsFailure: Int = 0
+                override val attemptsError: Int = 0
+            })
+        }
+    }
+}