Pool Kryo instances for efficiency. (#352)

Pooled Kryo

core/src/main/kotlin/net/corda/core/serialization/Kryo.kt

@@ -3,9 +3,11 @@ package net.corda.core.serialization
 import com.esotericsoftware.kryo.*
 import com.esotericsoftware.kryo.io.Input
 import com.esotericsoftware.kryo.io.Output
+import com.esotericsoftware.kryo.pool.KryoPool
 import com.esotericsoftware.kryo.serializers.JavaSerializer
 import com.esotericsoftware.kryo.serializers.MapSerializer
 import com.esotericsoftware.kryo.util.MapReferenceResolver
+import com.google.common.annotations.VisibleForTesting
 import net.corda.core.contracts.*
 import net.corda.core.crypto.*
 import net.corda.core.node.AttachmentsClassLoader
@@ -60,12 +62,9 @@ import kotlin.reflect.jvm.javaType
  */
 
 // A convenient instance of Kryo pre-configured with some useful things. Used as a default by various functions.
-private val THREAD_LOCAL_KRYO: ThreadLocal<Kryo> = ThreadLocal.withInitial { createKryo() }
+fun p2PKryo(): KryoPool = kryoPool
 // Same again, but this has whitelisting turned off for internal storage use only.
-private val INTERNAL_THREAD_LOCAL_KRYO: ThreadLocal<Kryo> = ThreadLocal.withInitial { createInternalKryo() }
+fun storageKryo(): KryoPool = internalKryoPool
-
-fun threadLocalP2PKryo(): Kryo = THREAD_LOCAL_KRYO.get()
-fun threadLocalStorageKryo(): Kryo = INTERNAL_THREAD_LOCAL_KRYO.get()
 
 /**
  * A type safe wrapper around a byte array that contains a serialised object. You can call [SerializedBytes.deserialize]
@@ -82,26 +81,34 @@ class SerializedBytes<T : Any>(bytes: ByteArray, val internalOnly: Boolean = fal
 private val KryoHeaderV0_1: OpaqueBytes = OpaqueBytes("corda\u0000\u0000\u0001".toByteArray())
 
 // Some extension functions that make deserialisation convenient and provide auto-casting of the result.
-fun <T : Any> ByteArray.deserialize(kryo: Kryo = threadLocalP2PKryo()): T {
+fun <T : Any> ByteArray.deserialize(kryo: KryoPool = p2PKryo()): T {
     Input(this).use {
         val header = OpaqueBytes(it.readBytes(8))
         if (header != KryoHeaderV0_1) {
             throw KryoException("Serialized bytes header does not match any known format.")
         }
         @Suppress("UNCHECKED_CAST")
-        return kryo.readClassAndObject(it) as T
+        return kryo.run { k -> k.readClassAndObject(it) as T }
     }
 }
 
-fun <T : Any> OpaqueBytes.deserialize(kryo: Kryo = threadLocalP2PKryo()): T {
+// TODO: The preferred usage is with a pool. Try and eliminate use of this from RPC.
+fun <T : Any> ByteArray.deserialize(kryo: Kryo): T = deserialize(kryo.asPool())
+
+fun <T : Any> OpaqueBytes.deserialize(kryo: KryoPool = p2PKryo()): T {
     return this.bytes.deserialize(kryo)
 }
 
 // The more specific deserialize version results in the bytes being cached, which is faster.
 @JvmName("SerializedBytesWireTransaction")
-fun SerializedBytes<WireTransaction>.deserialize(kryo: Kryo = threadLocalP2PKryo()): WireTransaction = WireTransaction.deserialize(this, kryo)
+fun SerializedBytes<WireTransaction>.deserialize(kryo: KryoPool = p2PKryo()): WireTransaction = WireTransaction.deserialize(this, kryo)
 
-fun <T : Any> SerializedBytes<T>.deserialize(kryo: Kryo = if (internalOnly) threadLocalStorageKryo() else threadLocalP2PKryo()): T = bytes.deserialize(kryo)
+fun <T : Any> SerializedBytes<T>.deserialize(kryo: KryoPool = if (internalOnly) storageKryo() else p2PKryo()): T = bytes.deserialize(kryo)
+
+fun <T : Any> SerializedBytes<T>.deserialize(kryo: Kryo): T = bytes.deserialize(kryo.asPool())
+
+// Internal adapter for use when we haven't yet converted to a pool, or for tests.
+private fun Kryo.asPool(): KryoPool = (KryoPool.Builder { this }.build())
 
 /**
  * A serialiser that avoids writing the wrapper class to the byte stream, thus ensuring [SerializedBytes] is a pure
@@ -122,7 +129,11 @@ object SerializedBytesSerializer : Serializer<SerializedBytes<Any>>() {
  * Can be called on any object to convert it to a byte array (wrapped by [SerializedBytes]), regardless of whether
  * the type is marked as serializable or was designed for it (so be careful!).
  */
-fun <T : Any> T.serialize(kryo: Kryo = threadLocalP2PKryo(), internalOnly: Boolean = false): SerializedBytes<T> {
+fun <T : Any> T.serialize(kryo: KryoPool = p2PKryo(), internalOnly: Boolean = false): SerializedBytes<T> {
+    return kryo.run { k -> serialize(k, internalOnly) }
+}
+
+fun <T : Any> T.serialize(kryo: Kryo, internalOnly: Boolean = false): SerializedBytes<T> {
     val stream = ByteArrayOutputStream()
     Output(stream).use {
         it.writeBytes(KryoHeaderV0_1.bytes)
@@ -399,14 +410,12 @@ object KotlinObjectSerializer : Serializer<DeserializeAsKotlinObjectDef>() {
 }
 
 // No ClassResolver only constructor.  MapReferenceResolver is the default as used by Kryo in other constructors.
-fun createInternalKryo(k: Kryo = CordaKryo(makeNoWhitelistClassResolver())): Kryo {
+private val internalKryoPool = KryoPool.Builder { DefaultKryoCustomizer.customize(CordaKryo(makeNoWhitelistClassResolver())) }.build()
-    return DefaultKryoCustomizer.customize(k)
+private val kryoPool = KryoPool.Builder { DefaultKryoCustomizer.customize(CordaKryo(makeStandardClassResolver())) }.build()
-}
 
 // No ClassResolver only constructor.  MapReferenceResolver is the default as used by Kryo in other constructors.
-fun createKryo(k: Kryo = CordaKryo(makeStandardClassResolver())): Kryo {
+@VisibleForTesting
-    return DefaultKryoCustomizer.customize(k)
+fun createTestKryo(): Kryo = DefaultKryoCustomizer.customize(CordaKryo(makeNoWhitelistClassResolver()))
-}
 
 /**
  * We need to disable whitelist checking during calls from our Kryo code to register a serializer, since it checks
@@ -475,22 +484,21 @@ inline fun <reified T : Any> Kryo.noReferencesWithin() {
 class NoReferencesSerializer<T>(val baseSerializer: Serializer<T>) : Serializer<T>() {
 
     override fun read(kryo: Kryo, input: Input, type: Class<T>): T {
-        val previousValue = kryo.setReferences(false)
+        return kryo.withoutReferences { baseSerializer.read(kryo, input, type) }
-        try {
-            return baseSerializer.read(kryo, input, type)
-        } finally {
-            kryo.references = previousValue
-        }
     }
 
     override fun write(kryo: Kryo, output: Output, obj: T) {
-        val previousValue = kryo.setReferences(false)
+        kryo.withoutReferences { baseSerializer.write(kryo, output, obj) }
-        try {
-            baseSerializer.write(kryo, output, obj)
-        } finally {
-            kryo.references = previousValue
     }
 }
+
+fun <T> Kryo.withoutReferences(block: () -> T): T {
+    val previousValue = setReferences(false)
+    try {
+        return block()
+    } finally {
+        references = previousValue
+    }
 }
 
 /**
@@ -524,17 +532,6 @@ var Kryo.attachmentStorage: AttachmentStorage?
         this.context.put(ATTACHMENT_STORAGE, value)
     }
 
-
-//TODO: It's a little workaround for serialization of HashMaps inside contract states.
-//Used in Merkle tree calculation. It doesn't cover all the cases of unstable serialization format.
-fun extendKryoHash(kryo: Kryo): Kryo {
-    return kryo.apply {
-        references = false
-        register(LinkedHashMap::class.java, MapSerializer())
-        register(HashMap::class.java, OrderedSerializer)
-    }
-}
-
 object OrderedSerializer : Serializer<HashMap<Any, Any>>() {
     override fun write(kryo: Kryo, output: Output, obj: HashMap<Any, Any>) {
         //Change a HashMap to LinkedHashMap.

core/src/main/kotlin/net/corda/core/serialization/SerializationToken.kt

@@ -5,7 +5,7 @@ import com.esotericsoftware.kryo.KryoException
 import com.esotericsoftware.kryo.Serializer
 import com.esotericsoftware.kryo.io.Input
 import com.esotericsoftware.kryo.io.Output
-import java.util.*
+import com.esotericsoftware.kryo.pool.KryoPool
 
 /**
  * The interfaces and classes in this file allow large, singleton style classes to
@@ -36,8 +36,6 @@ interface SerializationToken {
 
 /**
  * A Kryo serializer for [SerializeAsToken] implementations.
- *
- * This is registered in [createKryo].
  */
 class SerializeAsTokenSerializer<T : SerializeAsToken> : Serializer<T>() {
     override fun write(kryo: Kryo, output: Output, obj: T) {
@@ -76,8 +74,8 @@ class SerializeAsTokenSerializer<T : SerializeAsToken> : Serializer<T>() {
  * Then it is a case of using the companion object methods on [SerializeAsTokenSerializer] to set and clear context as necessary
  * on the Kryo instance when serializing to enable/disable tokenization.
  */
-class SerializeAsTokenContext(toBeTokenized: Any, kryo: Kryo = createKryo()) {
+class SerializeAsTokenContext(toBeTokenized: Any, kryoPool: KryoPool) {
-    internal val tokenToTokenized = HashMap<SerializationToken, SerializeAsToken>()
+    internal val tokenToTokenized = mutableMapOf<SerializationToken, SerializeAsToken>()
     internal var readOnly = false
 
     init {
@@ -90,9 +88,11 @@ class SerializeAsTokenContext(toBeTokenized: Any, kryo: Kryo = createKryo()) {
          * accidental registrations from occuring as these could not be deserialized in a deserialization-first
          * scenario if they are not part of this iniital context construction serialization.
          */
+        kryoPool.run { kryo ->
             SerializeAsTokenSerializer.setContext(kryo, this)
             toBeTokenized.serialize(kryo)
             SerializeAsTokenSerializer.clearContext(kryo)
+        }
         readOnly = true
     }
 }

core/src/main/kotlin/net/corda/core/transactions/MerkleTransaction.kt

@@ -3,13 +3,12 @@ package net.corda.core.transactions
 import net.corda.core.contracts.*
 import net.corda.core.crypto.*
 import net.corda.core.serialization.CordaSerializable
-import net.corda.core.serialization.createKryo
+import net.corda.core.serialization.p2PKryo
-import net.corda.core.serialization.extendKryoHash
 import net.corda.core.serialization.serialize
+import net.corda.core.serialization.withoutReferences
 
 fun <T : Any> serializedHash(x: T): SecureHash {
-    val kryo = extendKryoHash(createKryo()) // Dealing with HashMaps inside states.
+    return p2PKryo().run { kryo -> kryo.withoutReferences { x.serialize(kryo).hash } }
-    return x.serialize(kryo).hash
 }
 
 /**

core/src/main/kotlin/net/corda/core/transactions/WireTransaction.kt

@@ -1,6 +1,6 @@
 package net.corda.core.transactions
 
-import com.esotericsoftware.kryo.Kryo
+import com.esotericsoftware.kryo.pool.KryoPool
 import net.corda.core.contracts.*
 import net.corda.core.crypto.CompositeKey
 import net.corda.core.crypto.MerkleTree
@@ -10,8 +10,8 @@ import net.corda.core.indexOfOrThrow
 import net.corda.core.node.ServicesForResolution
 import net.corda.core.serialization.SerializedBytes
 import net.corda.core.serialization.deserialize
+import net.corda.core.serialization.p2PKryo
 import net.corda.core.serialization.serialize
-import net.corda.core.serialization.threadLocalP2PKryo
 import net.corda.core.utilities.Emoji
 import java.security.PublicKey
 
@@ -45,7 +45,7 @@ class WireTransaction(
     override val id: SecureHash by lazy { merkleTree.hash }
 
     companion object {
-        fun deserialize(data: SerializedBytes<WireTransaction>, kryo: Kryo = threadLocalP2PKryo()): WireTransaction {
+        fun deserialize(data: SerializedBytes<WireTransaction>, kryo: KryoPool = p2PKryo()): WireTransaction {
             val wtx = data.bytes.deserialize<WireTransaction>(kryo)
             wtx.cachedBytes = data
             return wtx

core/src/main/kotlin/net/corda/core/utilities/ProgressTracker.kt

@@ -88,7 +88,7 @@ class ProgressTracker(vararg steps: Step) {
     @CordaSerializable
     private data class Child(val tracker: ProgressTracker, @Transient val subscription: Subscription?)
 
-    private val childProgressTrackers = HashMap<Step, Child>()
+    private val childProgressTrackers = mutableMapOf<Step, Child>()
 
     init {
         steps.forEach {

core/src/test/kotlin/net/corda/core/crypto/PartialMerkleTreeTest.kt

@@ -1,18 +1,20 @@
 package net.corda.core.crypto
 
 
-import com.esotericsoftware.kryo.serializers.MapSerializer
+import com.esotericsoftware.kryo.KryoException
 import net.corda.contracts.asset.Cash
 import net.corda.core.contracts.*
 import net.corda.core.crypto.SecureHash.Companion.zeroHash
-import net.corda.core.serialization.*
+import net.corda.core.serialization.p2PKryo
-import net.corda.core.transactions.*
+import net.corda.core.serialization.serialize
-import net.corda.core.utilities.*
+import net.corda.core.transactions.WireTransaction
+import net.corda.core.utilities.DUMMY_NOTARY
+import net.corda.core.utilities.DUMMY_PUBKEY_1
+import net.corda.core.utilities.TEST_TX_TIME
 import net.corda.testing.MEGA_CORP
 import net.corda.testing.MEGA_CORP_PUBKEY
 import net.corda.testing.ledger
 import org.junit.Test
-import java.util.*
 import kotlin.test.*
 
 class PartialMerkleTreeTest {
@@ -208,15 +210,12 @@ class PartialMerkleTreeTest {
         assertFalse(pmt.verify(wrongRoot, inclHashes))
     }
 
-    @Test
+    @Test(expected = KryoException::class)
-    fun `hash map serialization`() {
+    fun `hash map serialization not allowed`() {
         val hm1 = hashMapOf("a" to 1, "b" to 2, "c" to 3, "e" to 4)
-        assert(serializedHash(hm1) == serializedHash(hm1.serialize().deserialize())) // It internally uses the ordered HashMap extension.
+        p2PKryo().run { kryo ->
-        val kryo = extendKryoHash(createKryo())
+            hm1.serialize(kryo)
-        assertTrue(kryo.getSerializer(HashMap::class.java) is OrderedSerializer)
+        }
-        assertTrue(kryo.getSerializer(LinkedHashMap::class.java) is MapSerializer)
-        val hm2 = hm1.serialize(kryo).deserialize(kryo)
-        assert(hm1.hashCode() == hm2.hashCode())
     }
 
     private fun makeSimpleCashWtx(notary: Party, timestamp: Timestamp? = null, attachments: List<SecureHash> = emptyList()): WireTransaction {

core/src/test/kotlin/net/corda/core/node/AttachmentClassLoaderTests.kt

@@ -1,5 +1,6 @@
 package net.corda.core.node
 
+import com.esotericsoftware.kryo.Kryo
 import net.corda.core.contracts.*
 import net.corda.core.crypto.CompositeKey
 import net.corda.core.crypto.Party
@@ -11,7 +12,9 @@ import net.corda.core.utilities.DUMMY_NOTARY
 import net.corda.testing.MEGA_CORP
 import net.corda.testing.node.MockAttachmentStorage
 import org.apache.commons.io.IOUtils
+import org.junit.After
 import org.junit.Assert
+import org.junit.Before
 import org.junit.Test
 import java.io.ByteArrayInputStream
 import java.io.ByteArrayOutputStream
@@ -75,6 +78,21 @@ class AttachmentClassLoaderTests {
 
     class ClassLoaderForTests : URLClassLoader(arrayOf(ISOLATED_CONTRACTS_JAR_PATH), FilteringClassLoader)
 
+    lateinit var kryo: Kryo
+    lateinit var kryo2: Kryo
+
+    @Before
+    fun setup() {
+        kryo = p2PKryo().borrow()
+        kryo2 = p2PKryo().borrow()
+    }
+
+    @After
+    fun teardown() {
+        p2PKryo().release(kryo)
+        p2PKryo().release(kryo2)
+    }
+
     @Test
     fun `dynamically load AnotherDummyContract from isolated contracts jar`() {
         val child = ClassLoaderForTests()
@@ -205,7 +223,6 @@ class AttachmentClassLoaderTests {
 
         val cl = AttachmentsClassLoader(arrayOf(att0, att1, att2).map { storage.openAttachment(it)!! }, FilteringClassLoader)
 
-        val kryo = createKryo()
         kryo.classLoader = cl
         kryo.addToWhitelist(contract.javaClass)
 
@@ -224,7 +241,6 @@ class AttachmentClassLoaderTests {
 
         assertNotNull(data.contract)
 
-        val kryo2 = createKryo()
         kryo2.addToWhitelist(data.contract.javaClass)
         val bytes = data.serialize(kryo2)
 
@@ -236,7 +252,6 @@ class AttachmentClassLoaderTests {
 
         val cl = AttachmentsClassLoader(arrayOf(att0, att1, att2).map { storage.openAttachment(it)!! }, FilteringClassLoader)
 
-        val kryo = createKryo()
         kryo.classLoader = cl
         kryo.addToWhitelist(Class.forName("net.corda.contracts.isolated.AnotherDummyContract", true, cl))
 
@@ -263,7 +278,6 @@ class AttachmentClassLoaderTests {
         val contract = contractClass.newInstance() as DummyContractBackdoor
         val tx = contract.generateInitial(MEGA_CORP.ref(0), 42, DUMMY_NOTARY)
         val storage = MockAttachmentStorage()
-        val kryo = createKryo()
         kryo.addToWhitelist(contract.javaClass)
         kryo.addToWhitelist(Class.forName("net.corda.contracts.isolated.AnotherDummyContract\$State", true, child))
         kryo.addToWhitelist(Class.forName("net.corda.contracts.isolated.AnotherDummyContract\$Commands\$Create", true, child))
@@ -279,7 +293,6 @@ class AttachmentClassLoaderTests {
 
         val bytes = wireTransaction.serialize(kryo)
 
-        val kryo2 = createKryo()
         // use empty attachmentStorage
         kryo2.attachmentStorage = storage
 
@@ -297,7 +310,6 @@ class AttachmentClassLoaderTests {
         val contract = contractClass.newInstance() as DummyContractBackdoor
         val tx = contract.generateInitial(MEGA_CORP.ref(0), 42, DUMMY_NOTARY)
         val storage = MockAttachmentStorage()
-        val kryo = createKryo()
 
         // todo - think about better way to push attachmentStorage down to serializer
         kryo.attachmentStorage = storage
@@ -310,7 +322,6 @@ class AttachmentClassLoaderTests {
 
         val bytes = wireTransaction.serialize(kryo)
 
-        val kryo2 = createKryo()
         // use empty attachmentStorage
         kryo2.attachmentStorage = MockAttachmentStorage()
 

core/src/test/kotlin/net/corda/core/serialization/KryoTests.kt

@@ -1,5 +1,6 @@
 package net.corda.core.serialization
 
+import com.esotericsoftware.kryo.Kryo
 import com.google.common.primitives.Ints
 import net.corda.core.crypto.*
 import net.corda.core.messaging.Ack
@@ -7,6 +8,8 @@ import org.assertj.core.api.Assertions.assertThat
 import org.assertj.core.api.Assertions.assertThatThrownBy
 import org.bouncycastle.jce.provider.BouncyCastleProvider
 import org.bouncycastle.pqc.jcajce.provider.BouncyCastlePQCProvider
+import org.junit.After
+import org.junit.Before
 import org.junit.Test
 import java.io.InputStream
 import java.security.Security
@@ -16,7 +19,17 @@ import kotlin.test.assertEquals
 
 class KryoTests {
 
-    private val kryo = createKryo()
+    private lateinit var kryo: Kryo
+
+    @Before
+    fun setup() {
+        kryo = p2PKryo().borrow()
+    }
+
+    @After
+    fun teardown() {
+        p2PKryo().release(kryo)
+    }
 
     @Test
     fun ok() {

core/src/test/kotlin/net/corda/core/serialization/SerializationTokenTest.kt

@@ -15,12 +15,13 @@ class SerializationTokenTest {
 
     @Before
     fun setup() {
-        kryo = threadLocalStorageKryo()
+        kryo = storageKryo().borrow()
     }
 
     @After
     fun cleanup() {
         SerializeAsTokenSerializer.clearContext(kryo)
+        storageKryo().release(kryo)
     }
 
     // Large tokenizable object so we can tell from the smaller number of serialized bytes it was actually tokenized
@@ -38,7 +39,7 @@ class SerializationTokenTest {
     @Test
     fun `write token and read tokenizable`() {
         val tokenizableBefore = LargeTokenizable()
-        val context = SerializeAsTokenContext(tokenizableBefore, kryo)
+        val context = SerializeAsTokenContext(tokenizableBefore, storageKryo())
         SerializeAsTokenSerializer.setContext(kryo, context)
         val serializedBytes = tokenizableBefore.serialize(kryo)
         assertThat(serializedBytes.size).isLessThan(tokenizableBefore.numBytes)
@@ -51,7 +52,7 @@ class SerializationTokenTest {
     @Test
     fun `write and read singleton`() {
         val tokenizableBefore = UnitSerializeAsToken()
-        val context = SerializeAsTokenContext(tokenizableBefore, kryo)
+        val context = SerializeAsTokenContext(tokenizableBefore, storageKryo())
         SerializeAsTokenSerializer.setContext(kryo, context)
         val serializedBytes = tokenizableBefore.serialize(kryo)
         val tokenizableAfter = serializedBytes.deserialize(kryo)
@@ -61,7 +62,7 @@ class SerializationTokenTest {
     @Test(expected = UnsupportedOperationException::class)
     fun `new token encountered after context init`() {
         val tokenizableBefore = UnitSerializeAsToken()
-        val context = SerializeAsTokenContext(emptyList<Any>(), kryo)
+        val context = SerializeAsTokenContext(emptyList<Any>(), storageKryo())
         SerializeAsTokenSerializer.setContext(kryo, context)
         tokenizableBefore.serialize(kryo)
     }
@@ -69,9 +70,9 @@ class SerializationTokenTest {
     @Test(expected = UnsupportedOperationException::class)
     fun `deserialize unregistered token`() {
         val tokenizableBefore = UnitSerializeAsToken()
-        val context = SerializeAsTokenContext(emptyList<Any>(), kryo)
+        val context = SerializeAsTokenContext(emptyList<Any>(), storageKryo())
         SerializeAsTokenSerializer.setContext(kryo, context)
-        val serializedBytes = tokenizableBefore.toToken(SerializeAsTokenContext(emptyList<Any>(), kryo)).serialize(kryo)
+        val serializedBytes = tokenizableBefore.toToken(SerializeAsTokenContext(emptyList<Any>(), storageKryo())).serialize(kryo)
         serializedBytes.deserialize(kryo)
     }
 
@@ -84,7 +85,7 @@ class SerializationTokenTest {
     @Test(expected = KryoException::class)
     fun `deserialize non-token`() {
         val tokenizableBefore = UnitSerializeAsToken()
-        val context = SerializeAsTokenContext(tokenizableBefore, kryo)
+        val context = SerializeAsTokenContext(tokenizableBefore, storageKryo())
         SerializeAsTokenSerializer.setContext(kryo, context)
         val stream = ByteArrayOutputStream()
         Output(stream).use {
@@ -106,7 +107,7 @@ class SerializationTokenTest {
     @Test(expected = KryoException::class)
     fun `token returns unexpected type`() {
         val tokenizableBefore = WrongTypeSerializeAsToken()
-        val context = SerializeAsTokenContext(tokenizableBefore, kryo)
+        val context = SerializeAsTokenContext(tokenizableBefore, storageKryo())
         SerializeAsTokenSerializer.setContext(kryo, context)
         val serializedBytes = tokenizableBefore.serialize(kryo)
         serializedBytes.deserialize(kryo)

core/src/test/kotlin/net/corda/core/utilities/ProgressTrackerTest.kt

@@ -4,7 +4,7 @@ import com.esotericsoftware.kryo.Kryo
 import com.esotericsoftware.kryo.KryoSerializable
 import com.esotericsoftware.kryo.io.Input
 import com.esotericsoftware.kryo.io.Output
-import net.corda.core.serialization.createInternalKryo
+import net.corda.core.serialization.createTestKryo
 import net.corda.core.serialization.serialize
 import org.junit.Before
 import org.junit.Test
@@ -106,7 +106,7 @@ class ProgressTrackerTest {
             }
         }
 
-        val kryo = createInternalKryo().apply {
+        val kryo = createTestKryo().apply {
             // This is required to make sure Kryo walks through the auto-generated members for the lambda below.
             fieldSerializerConfig.isIgnoreSyntheticFields = false
         }

node/src/main/kotlin/net/corda/node/serialization/DefaultWhitelist.kt

@@ -11,6 +11,9 @@ import java.time.LocalDate
 import java.time.Period
 import java.util.*
 
+/**
+ * NOTE: We do not whitelist [HashMap] or [HashSet] since they are unstable under serialization.
+ */
 class DefaultWhitelist : CordaPluginRegistry() {
     override fun customizeSerialization(custom: SerializationCustomization): Boolean {
         custom.apply {
@@ -41,7 +44,6 @@ class DefaultWhitelist : CordaPluginRegistry() {
             addToWhitelist(java.time.Instant::class.java)
             addToWhitelist(java.time.LocalDate::class.java)
             addToWhitelist(java.util.Collections.singletonMap("A", "B").javaClass)
-            addToWhitelist(java.util.HashMap::class.java)
             addToWhitelist(java.util.LinkedHashMap::class.java)
             addToWhitelist(BigDecimal::class.java)
             addToWhitelist(LocalDate::class.java)

node/src/main/kotlin/net/corda/node/services/messaging/CordaRPCClientImpl.kt

@@ -113,18 +113,20 @@ class CordaRPCClientImpl(private val session: ClientSession,
     @GuardedBy("sessionLock")
     private val addressToQueuedObservables = CacheBuilder.newBuilder().weakValues().build<String, QueuedObservable>()
     // This is used to hold a reference counted hard reference when we know there are subscribers.
-    private val hardReferencesToQueuedObservables = mutableSetOf<QueuedObservable>()
+    private val hardReferencesToQueuedObservables = Collections.synchronizedSet(mutableSetOf<QueuedObservable>())
 
     private var producer: ClientProducer? = null
 
-    private inner class ObservableDeserializer(private val qName: String,
+    class ObservableDeserializer() : Serializer<Observable<Any>>() {
-                                               private val rpcName: String,
-                                               private val rpcLocation: Throwable) : Serializer<Observable<Any>>() {
         override fun read(kryo: Kryo, input: Input, type: Class<Observable<Any>>): Observable<Any> {
+            val qName = kryo.context[RPCKryoQNameKey] as String
+            val rpcName = kryo.context[RPCKryoMethodNameKey] as String
+            val rpcLocation = kryo.context[RPCKryoLocationKey] as Throwable
+            val rpcClient = kryo.context[RPCKryoClientKey] as CordaRPCClientImpl
             val handle = input.readInt(true)
-            val ob = sessionLock.withLock {
+            val ob = rpcClient.sessionLock.withLock {
-                addressToQueuedObservables.getIfPresent(qName) ?: QueuedObservable(qName, rpcName, rpcLocation, this).apply {
+                rpcClient.addressToQueuedObservables.getIfPresent(qName) ?: rpcClient.QueuedObservable(qName, rpcName, rpcLocation).apply {
-                    addressToQueuedObservables.put(qName, this)
+                    rpcClient.addressToQueuedObservables.put(qName, this)
                 }
             }
             val result = ob.getForHandle(handle)
@@ -182,9 +184,17 @@ class CordaRPCClientImpl(private val session: ClientSession,
 
             checkMethodVersion(method)
 
-            // sendRequest may return a reconfigured Kryo if the method returns observables.
+            val msg: ClientMessage = createMessage(method)
-            val kryo: Kryo = sendRequest(args, location, method) ?: createRPCKryo()
+            // We could of course also check the return type of the method to see if it's Observable, but I'd
-            val next: ErrorOr<*> = receiveResponse(kryo, method, timeout)
+            // rather haved the annotation be used consistently.
+            val returnsObservables = method.isAnnotationPresent(RPCReturnsObservables::class.java)
+            val kryo = if (returnsObservables) maybePrepareForObservables(location, method, msg) else createRPCKryoForDeserialization(this@CordaRPCClientImpl)
+            val next: ErrorOr<*> = try {
+                sendRequest(args, msg)
+                receiveResponse(kryo, method, timeout)
+            } finally {
+                releaseRPCKryoForDeserialization(kryo)
+            }
             rpcLog.debug { "<- RPC <- ${method.name} = $next" }
             return unwrapOrThrow(next)
         }
@@ -215,22 +225,18 @@ class CordaRPCClientImpl(private val session: ClientSession,
             return next
         }
 
-        private fun sendRequest(args: Array<out Any>?, location: Throwable, method: Method): Kryo? {
+        private fun sendRequest(args: Array<out Any>?, msg: ClientMessage) {
-            // We could of course also check the return type of the method to see if it's Observable, but I'd
-            // rather haved the annotation be used consistently.
-            val returnsObservables = method.isAnnotationPresent(RPCReturnsObservables::class.java)
-
             sessionLock.withLock {
-                val msg: ClientMessage = createMessage(method)
+                val argsKryo = createRPCKryoForDeserialization(this@CordaRPCClientImpl)
-                val kryo = if (returnsObservables) maybePrepareForObservables(location, method, msg) else null
                 val serializedArgs = try {
-                    (args ?: emptyArray<Any?>()).serialize(createRPCKryo())
+                    (args ?: emptyArray<Any?>()).serialize(argsKryo)
                 } catch (e: KryoException) {
                     throw RPCException("Could not serialize RPC arguments", e)
+                } finally {
+                    releaseRPCKryoForDeserialization(argsKryo)
                 }
                 msg.writeBodyBufferBytes(serializedArgs.bytes)
                 producer!!.send(ArtemisMessagingComponent.RPC_REQUESTS_QUEUE, msg)
-                return kryo
             }
         }
 
@@ -242,7 +248,7 @@ class CordaRPCClientImpl(private val session: ClientSession,
             msg.putLongProperty(ClientRPCRequestMessage.OBSERVATIONS_TO, observationsId)
             // And make sure that we deserialise observable handles so that they're linked to the right
             // queue. Also record a bit of metadata for debugging purposes.
-            return createRPCKryo(observableSerializer = ObservableDeserializer(observationsQueueName, method.name, location))
+            return createRPCKryoForDeserialization(this@CordaRPCClientImpl, observationsQueueName, method.name, location)
         }
 
         private fun createMessage(method: Method): ClientMessage {
@@ -278,8 +284,7 @@ class CordaRPCClientImpl(private val session: ClientSession,
     @ThreadSafe
     private inner class QueuedObservable(private val qName: String,
                                          private val rpcName: String,
-                                         private val rpcLocation: Throwable,
+                                         private val rpcLocation: Throwable) {
-                                         private val observableDeserializer: ObservableDeserializer) {
         private val root = PublishSubject.create<MarshalledObservation>()
         private val rootShared = root.doOnUnsubscribe { close() }.share()
 
@@ -345,8 +350,10 @@ class CordaRPCClientImpl(private val session: ClientSession,
 
         private fun deliver(msg: ClientMessage) {
             msg.acknowledge()
-            val kryo = createRPCKryo(observableSerializer = observableDeserializer)
+            val kryo = createRPCKryoForDeserialization(this@CordaRPCClientImpl, qName, rpcName, rpcLocation)
-            val received: MarshalledObservation = msg.deserialize(kryo)
+            val received: MarshalledObservation = try { msg.deserialize(kryo) } finally {
+                releaseRPCKryoForDeserialization(kryo)
+            }
             rpcLog.debug { "<- Observable [$rpcName] <- Received $received" }
             synchronized(observables) {
                 // Force creation of the buffer if it doesn't already exist.

node/src/main/kotlin/net/corda/node/services/messaging/RPCDispatcher.kt

@@ -42,6 +42,8 @@ abstract class RPCDispatcher(val ops: RPCOps, val userService: RPCUserService, v
 
     private val queueToSubscription = HashMultimap.create<String, Subscription>()
 
+    private val handleCounter = AtomicInteger()
+
     // Created afresh for every RPC that is annotated as returning observables. Every time an observable is
     // encountered either in the RPC response or in an object graph that is being emitted by one of those
     // observables, the handle counter is incremented and the server-side observable is subscribed to. The
@@ -49,41 +51,48 @@ abstract class RPCDispatcher(val ops: RPCOps, val userService: RPCUserService, v
     //
     // When the observables are deserialised on the client side, the handle is read from the byte stream and
     // the queue is filtered to extract just those observations.
-    private inner class ObservableSerializer(private val toQName: String) : Serializer<Observable<Any>>() {
+    class ObservableSerializer() : Serializer<Observable<Any>>() {
-        private val handleCounter = AtomicInteger()
+        private fun toQName(kryo: Kryo): String = kryo.context[RPCKryoQNameKey] as String
+        private fun toDispatcher(kryo: Kryo): RPCDispatcher = kryo.context[RPCKryoDispatcherKey] as RPCDispatcher
 
         override fun read(kryo: Kryo, input: Input, type: Class<Observable<Any>>): Observable<Any> {
             throw UnsupportedOperationException("not implemented")
         }
 
         override fun write(kryo: Kryo, output: Output, obj: Observable<Any>) {
-            val handle = handleCounter.andIncrement
+            val qName = toQName(kryo)
+            val dispatcher = toDispatcher(kryo)
+            val handle = dispatcher.handleCounter.andIncrement
             output.writeInt(handle, true)
             // Observables can do three kinds of callback: "next" with a content object, "completed" and "error".
             // Materializing the observable converts these three kinds of callback into a single stream of objects
             // representing what happened, which is useful for us to send over the wire.
             val subscription = obj.materialize().subscribe { materialised: Notification<out Any> ->
-                val newKryo = createRPCKryo(observableSerializer = this@ObservableSerializer)
+                val newKryo = createRPCKryoForSerialization(qName, dispatcher)
-                val bits = MarshalledObservation(handle, materialised).serialize(newKryo)
+                val bits = try { MarshalledObservation(handle, materialised).serialize(newKryo) } finally {
-                rpcLog.debug("RPC sending observation: $materialised")
+                    releaseRPCKryoForSerialization(newKryo)
-                send(bits, toQName)
                 }
-            synchronized(queueToSubscription) {
+                rpcLog.debug("RPC sending observation: $materialised")
-                queueToSubscription.put(toQName, subscription)
+                dispatcher.send(bits, qName)
+            }
+            synchronized(dispatcher.queueToSubscription) {
+                dispatcher.queueToSubscription.put(qName, subscription)
             }
         }
     }
 
     fun dispatch(msg: ClientRPCRequestMessage) {
         val (argsBytes, replyTo, observationsTo, methodName) = msg
-        val kryo = createRPCKryo(observableSerializer = if (observationsTo != null) ObservableSerializer(observationsTo) else null)
 
         val response: ErrorOr<Any> = ErrorOr.catch {
             val method = methodTable[methodName] ?: throw RPCException("Received RPC for unknown method $methodName - possible client/server version skew?")
             if (method.isAnnotationPresent(RPCReturnsObservables::class.java) && observationsTo == null)
                 throw RPCException("Received RPC without any destination for observations, but the RPC returns observables")
 
-            val args = argsBytes.deserialize(kryo)
+            val kryo = createRPCKryoForSerialization(observationsTo, this)
+            val args = try { argsBytes.deserialize(kryo) } finally {
+                releaseRPCKryoForSerialization(kryo)
+            }
 
             rpcLog.debug { "-> RPC -> $methodName(${args.joinToString()})    [reply to $replyTo]" }
 
@@ -95,13 +104,15 @@ abstract class RPCDispatcher(val ops: RPCOps, val userService: RPCUserService, v
         }
         rpcLog.debug { "<- RPC <- $methodName = $response " }
 
-
         // Serialise, or send back a simple serialised ErrorOr structure if we couldn't do it.
+        val kryo = createRPCKryoForSerialization(observationsTo, this)
         val responseBits = try {
             response.serialize(kryo)
         } catch (e: KryoException) {
             rpcLog.error("Failed to respond to inbound RPC $methodName", e)
             ErrorOr.of(e).serialize(kryo)
+        } finally {
+            releaseRPCKryoForSerialization(kryo)
         }
         send(responseBits, replyTo)
     }

node/src/main/kotlin/net/corda/node/services/messaging/RPCStructures.kt

@@ -7,6 +7,7 @@ import com.esotericsoftware.kryo.Registration
 import com.esotericsoftware.kryo.Serializer
 import com.esotericsoftware.kryo.io.Input
 import com.esotericsoftware.kryo.io.Output
+import com.esotericsoftware.kryo.pool.KryoPool
 import com.google.common.util.concurrent.ListenableFuture
 import net.corda.core.flows.FlowException
 import net.corda.core.serialization.*
@@ -88,10 +89,16 @@ object ClassSerializer : Serializer<Class<*>>() {
 @CordaSerializable
 class PermissionException(msg: String) : RuntimeException(msg)
 
+object RPCKryoClientKey
+object RPCKryoDispatcherKey
+object RPCKryoQNameKey
+object RPCKryoMethodNameKey
+object RPCKryoLocationKey
+
 // The Kryo used for the RPC wire protocol. Every type in the wire protocol is listed here explicitly.
 // This is annoying to write out, but will make it easier to formalise the wire protocol when the time comes,
 // because we can see everything we're using in one place.
-private class RPCKryo(observableSerializer: Serializer<Observable<Any>>? = null) : CordaKryo(makeStandardClassResolver()) {
+private class RPCKryo(observableSerializer: Serializer<Observable<Any>>) : CordaKryo(makeStandardClassResolver()) {
     init {
         DefaultKryoCustomizer.customize(this)
 
@@ -99,24 +106,13 @@ private class RPCKryo(observableSerializer: Serializer<Observable<Any>>? = null)
         register(Class::class.java, ClassSerializer)
         register(MultipartStream.ItemInputStream::class.java, InputStreamSerializer)
         register(MarshalledObservation::class.java, ImmutableClassSerializer(MarshalledObservation::class))
-    }
+        register(Observable::class.java, observableSerializer)
-
-    // TODO: workaround to prevent Observable registration conflict when using plugin registered kyro classes
-    private val observableRegistration: Registration? = observableSerializer?.let { register(Observable::class.java, it, 10000) }
-
-    private val listenableFutureRegistration: Registration? = observableSerializer?.let {
-        // Register ListenableFuture by making use of Observable serialisation.
-        // TODO Serialisation could be made more efficient as a future can only emit one value (or exception)
         @Suppress("UNCHECKED_CAST")
         register(ListenableFuture::class,
-                read = { kryo, input -> it.read(kryo, input, Observable::class.java as Class<Observable<Any>>).toFuture() },
+                read = { kryo, input -> observableSerializer.read(kryo, input, Observable::class.java as Class<Observable<Any>>).toFuture() },
-                write = { kryo, output, obj -> it.write(kryo, output, obj.toObservable()) }
+                write = { kryo, output, obj -> observableSerializer.write(kryo, output, obj.toObservable()) }
         )
-    }
+        register(
-
-    // Avoid having to worry about the subtypes of FlowException by converting all of them to just FlowException.
-    // This is a temporary hack until a proper serialisation mechanism is in place.
-    private val flowExceptionRegistration: Registration = register(
                 FlowException::class,
                 read = { kryo, input ->
                     val message = input.readString()
@@ -130,18 +126,48 @@ private class RPCKryo(observableSerializer: Serializer<Observable<Any>>? = null)
                     kryo.writeObjectOrNull(output, obj.cause, Throwable::class.java)
                 }
         )
+    }
 
     override fun getRegistration(type: Class<*>): Registration {
-        if (Observable::class.java.isAssignableFrom(type))
+        val annotated = context[RPCKryoQNameKey] != null
-            return observableRegistration ?:
+        if (Observable::class.java.isAssignableFrom(type)) {
-                    throw IllegalStateException("This RPC was not annotated with @RPCReturnsObservables")
+            return if (annotated) super.getRegistration(Observable::class.java)
-        if (ListenableFuture::class.java.isAssignableFrom(type))
+            else throw IllegalStateException("This RPC was not annotated with @RPCReturnsObservables")
-            return listenableFutureRegistration ?:
+        }
-                    throw IllegalStateException("This RPC was not annotated with @RPCReturnsObservables")
+        if (ListenableFuture::class.java.isAssignableFrom(type)) {
+            return if (annotated) super.getRegistration(ListenableFuture::class.java)
+            else throw IllegalStateException("This RPC was not annotated with @RPCReturnsObservables")
+        }
         if (FlowException::class.java.isAssignableFrom(type))
-            return flowExceptionRegistration
+            return super.getRegistration(FlowException::class.java)
         return super.getRegistration(type)
     }
 }
 
-fun createRPCKryo(observableSerializer: Serializer<Observable<Any>>? = null): Kryo = RPCKryo(observableSerializer)
+private val rpcSerKryoPool = KryoPool.Builder { RPCKryo(RPCDispatcher.ObservableSerializer()) }.build()
+
+fun createRPCKryoForSerialization(qName: String? = null, dispatcher: RPCDispatcher? = null): Kryo {
+    val kryo = rpcSerKryoPool.borrow()
+    kryo.context.put(RPCKryoQNameKey, qName)
+    kryo.context.put(RPCKryoDispatcherKey, dispatcher)
+    return kryo
+}
+
+fun releaseRPCKryoForSerialization(kryo: Kryo) {
+    rpcSerKryoPool.release(kryo)
+}
+
+private val rpcDesKryoPool = KryoPool.Builder { RPCKryo(CordaRPCClientImpl.ObservableDeserializer()) }.build()
+
+fun createRPCKryoForDeserialization(rpcClient: CordaRPCClientImpl, qName: String? = null, rpcName: String? = null, rpcLocation: Throwable? = null): Kryo {
+    val kryo = rpcDesKryoPool.borrow()
+    kryo.context.put(RPCKryoClientKey, rpcClient)
+    kryo.context.put(RPCKryoQNameKey, qName)
+    kryo.context.put(RPCKryoMethodNameKey, rpcName)
+    kryo.context.put(RPCKryoLocationKey, rpcLocation)
+    return kryo
+}
+
+fun releaseRPCKryoForDeserialization(kryo: Kryo) {
+    rpcDesKryoPool.release(kryo)
+}

node/src/main/kotlin/net/corda/node/services/persistence/DBCheckpointStorage.kt

@@ -4,7 +4,7 @@ import net.corda.core.crypto.SecureHash
 import net.corda.core.serialization.SerializedBytes
 import net.corda.core.serialization.deserialize
 import net.corda.core.serialization.serialize
-import net.corda.core.serialization.threadLocalStorageKryo
+import net.corda.core.serialization.storageKryo
 import net.corda.node.services.api.Checkpoint
 import net.corda.node.services.api.CheckpointStorage
 import net.corda.node.utilities.*
@@ -39,7 +39,7 @@ class DBCheckpointStorage : CheckpointStorage {
     private val checkpointStorage = synchronizedMap(CheckpointMap())
 
     override fun addCheckpoint(checkpoint: Checkpoint) {
-        checkpointStorage.put(checkpoint.id, checkpoint.serialize(threadLocalStorageKryo(), true))
+        checkpointStorage.put(checkpoint.id, checkpoint.serialize(storageKryo(), true))
     }
 
     override fun removeCheckpoint(checkpoint: Checkpoint) {

node/src/main/kotlin/net/corda/node/services/statemachine/StateMachineManager.kt

@@ -6,6 +6,7 @@ import co.paralleluniverse.io.serialization.kryo.KryoSerializer
 import co.paralleluniverse.strands.Strand
 import com.codahale.metrics.Gauge
 import com.esotericsoftware.kryo.Kryo
+import com.esotericsoftware.kryo.pool.KryoPool
 import com.google.common.collect.HashMultimap
 import com.google.common.util.concurrent.ListenableFuture
 import kotlinx.support.jdk8.collections.removeIf
@@ -71,6 +72,11 @@ class StateMachineManager(val serviceHub: ServiceHubInternal,
 
     inner class FiberScheduler : FiberExecutorScheduler("Same thread scheduler", executor)
 
+    private val quasarKryoPool = KryoPool.Builder {
+        val serializer = Fiber.getFiberSerializer(false) as KryoSerializer
+        DefaultKryoCustomizer.customize(serializer.kryo)
+    }.build()
+
     companion object {
         private val logger = loggerFor<StateMachineManager>()
         internal val sessionTopic = TopicSession("platform.session")
@@ -354,31 +360,22 @@ class StateMachineManager(val serviceHub: ServiceHubInternal,
     }
 
     private fun serializeFiber(fiber: FlowStateMachineImpl<*>): SerializedBytes<FlowStateMachineImpl<*>> {
-        val kryo = quasarKryo()
+        return quasarKryo().run { kryo ->
             // add the map of tokens -> tokenizedServices to the kyro context
             SerializeAsTokenSerializer.setContext(kryo, serializationContext)
-        return fiber.serialize(kryo)
+            fiber.serialize(kryo)
+        }
     }
 
     private fun deserializeFiber(checkpoint: Checkpoint): FlowStateMachineImpl<*> {
-        val kryo = quasarKryo()
+        return quasarKryo().run { kryo ->
             // put the map of token -> tokenized into the kryo context
             SerializeAsTokenSerializer.setContext(kryo, serializationContext)
-        return checkpoint.serializedFiber.deserialize(kryo).apply { fromCheckpoint = true }
+            checkpoint.serializedFiber.deserialize(kryo).apply { fromCheckpoint = true }
+        }
     }
 
-    private fun quasarKryo(): Kryo {
+    private fun quasarKryo(): KryoPool = quasarKryoPool
-        val serializer = Fiber.getFiberSerializer(false) as KryoSerializer
-        return createKryo(serializer.kryo).apply {
-            // Because we like to stick a Kryo object in a ThreadLocal to speed things up a bit, we can end up trying to
-            // serialise the Kryo object itself when suspending a fiber. That's dumb, useless AND can cause crashes, so
-            // we avoid it here.  This is checkpointing specific.
-            register(Kryo::class,
-                    read = { kryo, input -> createKryo((Fiber.getFiberSerializer() as KryoSerializer).kryo) },
-                    write = { kryo, output, obj -> }
-            )
-        }
-    }
 
     private fun <T> createFiber(logic: FlowLogic<T>): FlowStateMachineImpl<T> {
         val id = StateMachineRunId.createRandom()

node/src/main/kotlin/net/corda/node/services/vault/NodeVaultService.kt

@@ -8,7 +8,6 @@ import net.corda.core.ThreadBox
 import net.corda.core.bufferUntilSubscribed
 import net.corda.core.contracts.*
 import net.corda.core.crypto.AbstractParty
-import net.corda.core.crypto.AnonymousParty
 import net.corda.core.crypto.CompositeKey
 import net.corda.core.crypto.SecureHash
 import net.corda.core.node.ServiceHub
@@ -16,9 +15,9 @@ import net.corda.core.node.services.Vault
 import net.corda.core.node.services.VaultService
 import net.corda.core.node.services.unconsumedStates
 import net.corda.core.serialization.SingletonSerializeAsToken
-import net.corda.core.serialization.createKryo
 import net.corda.core.serialization.deserialize
 import net.corda.core.serialization.serialize
+import net.corda.core.serialization.storageKryo
 import net.corda.core.tee
 import net.corda.core.transactions.TransactionBuilder
 import net.corda.core.transactions.WireTransaction
@@ -76,8 +75,7 @@ class NodeVaultService(private val services: ServiceHub, dataSourceProperties: P
                             index = it.key.index
                             stateStatus = Vault.StateStatus.UNCONSUMED
                             contractStateClassName = it.value.state.data.javaClass.name
-                            // TODO: revisit Kryo bug when using THREAD_LOCAL_KYRO
+                            contractState = it.value.state.serialize(storageKryo()).bytes
-                            contractState = it.value.state.serialize(createKryo()).bytes
                             notaryName = it.value.state.notary.name
                             notaryKey = it.value.state.notary.owningKey.toBase58String()
                             recordedTime = services.clock.instant()
@@ -165,8 +163,7 @@ class NodeVaultService(private val services: ServiceHub, dataSourceProperties: P
                 Sequence{iterator}
                         .map { it ->
                             val stateRef = StateRef(SecureHash.parse(it.txId), it.index)
-                            // TODO: revisit Kryo bug when using THREAD_LOCAL_KRYO
+                            val state = it.contractState.deserialize<TransactionState<T>>(storageKryo())
-                            val state = it.contractState.deserialize<TransactionState<T>>(createKryo())
                             StateAndRef(state, stateRef)
                         }
             }
@@ -184,7 +181,7 @@ class NodeVaultService(private val services: ServiceHub, dataSourceProperties: P
                                 .and(VaultSchema.VaultStates::index eq it.index)
                         result.get()?.each {
                             val stateRef = StateRef(SecureHash.parse(it.txId), it.index)
-                            val state = it.contractState.deserialize<TransactionState<*>>()
+                            val state = it.contractState.deserialize<TransactionState<*>>(storageKryo())
                             results += StateAndRef(state, stateRef)
                         }
                     }
@@ -353,7 +350,7 @@ class NodeVaultService(private val services: ServiceHub, dataSourceProperties: P
             while (rs.next()) {
                 val txHash = SecureHash.parse(rs.getString(1))
                 val index = rs.getInt(2)
-                val state = rs.getBytes(3).deserialize<TransactionState<ContractState>>(createKryo())
+                val state = rs.getBytes(3).deserialize<TransactionState<ContractState>>(storageKryo())
                 consumedStates.add(StateAndRef(state, StateRef(txHash, index)))
             }
         }

node/src/main/kotlin/net/corda/node/utilities/JDBCHashMap.kt

@@ -3,7 +3,7 @@ package net.corda.node.utilities
 import net.corda.core.serialization.SerializedBytes
 import net.corda.core.serialization.deserialize
 import net.corda.core.serialization.serialize
-import net.corda.core.serialization.threadLocalStorageKryo
+import net.corda.core.serialization.storageKryo
 import net.corda.core.utilities.loggerFor
 import net.corda.core.utilities.trace
 import org.jetbrains.exposed.sql.*
@@ -65,7 +65,7 @@ fun bytesToBlob(value: SerializedBytes<*>, finalizables: MutableList<() -> Unit>
     return blob
 }
 
-fun serializeToBlob(value: Any, finalizables: MutableList<() -> Unit>): Blob = bytesToBlob(value.serialize(threadLocalStorageKryo(), true), finalizables)
+fun serializeToBlob(value: Any, finalizables: MutableList<() -> Unit>): Blob = bytesToBlob(value.serialize(storageKryo(), true), finalizables)
 
 fun <T : Any> bytesFromBlob(blob: Blob): SerializedBytes<T> {
     try {

node/src/test/kotlin/net/corda/node/services/database/RequeryConfigurationTest.kt

@@ -10,8 +10,8 @@ import net.corda.core.crypto.DigitalSignature
 import net.corda.core.crypto.NullPublicKey
 import net.corda.core.crypto.SecureHash
 import net.corda.core.node.services.Vault
-import net.corda.core.serialization.createKryo
 import net.corda.core.serialization.serialize
+import net.corda.core.serialization.storageKryo
 import net.corda.core.transactions.SignedTransaction
 import net.corda.core.transactions.WireTransaction
 import net.corda.core.utilities.DUMMY_NOTARY
@@ -128,7 +128,7 @@ class RequeryConfigurationTest {
             index = txnState.index
             stateStatus = Vault.StateStatus.UNCONSUMED
             contractStateClassName = DummyContract.SingleOwnerState::class.java.name
-            contractState = DummyContract.SingleOwnerState(owner = DUMMY_PUBKEY_1).serialize(createKryo()).bytes
+            contractState = DummyContract.SingleOwnerState(owner = DUMMY_PUBKEY_1).serialize(storageKryo()).bytes
             notaryName = txn.tx.notary!!.name
             notaryKey = txn.tx.notary!!.owningKey.toBase58String()
             recordedTime = Instant.now()

samples/irs-demo/src/test/kotlin/net/corda/irs/testing/IRSTests.kt

@@ -1,7 +1,6 @@
 package net.corda.irs.testing
 
 import net.corda.core.contracts.*
-import net.corda.core.node.recordTransactions
 import net.corda.core.seconds
 import net.corda.core.transactions.SignedTransaction
 import net.corda.core.utilities.DUMMY_NOTARY
@@ -77,8 +76,8 @@ fun createDummyIRS(irsSelect: Int): InterestRateSwap.State {
                     expression = Expression("( fixedLeg.notional.pennies * (fixedLeg.fixedRate.ratioUnit.value)) -" +
                             "(floatingLeg.notional.pennies * (calculation.fixingSchedule.get(context.getDate('currentDate')).rate.ratioUnit.value))"),
 
-                    floatingLegPaymentSchedule = HashMap(),
+                    floatingLegPaymentSchedule = mutableMapOf(),
-                    fixedLegPaymentSchedule = HashMap()
+                    fixedLegPaymentSchedule = mutableMapOf()
             )
 
             val EUR = currency("EUR")
@@ -167,8 +166,8 @@ fun createDummyIRS(irsSelect: Int): InterestRateSwap.State {
                     expression = Expression("( fixedLeg.notional.pennies * (fixedLeg.fixedRate.ratioUnit.value)) -" +
                             "(floatingLeg.notional.pennies * (calculation.fixingSchedule.get(context.getDate('currentDate')).rate.ratioUnit.value))"),
 
-                    floatingLegPaymentSchedule = HashMap(),
+                    floatingLegPaymentSchedule = mutableMapOf(),
-                    fixedLegPaymentSchedule = HashMap()
+                    fixedLegPaymentSchedule = mutableMapOf()
             )
 
             val EUR = currency("EUR")
@@ -413,7 +412,7 @@ class IRSTests {
     @Test
     fun `ensure failure occurs when no events in fix schedule`() {
         val irs = singleIRS()
-        val emptySchedule = HashMap<LocalDate, FixedRatePaymentEvent>()
+        val emptySchedule = mutableMapOf<LocalDate, FixedRatePaymentEvent>()
         transaction {
             output() {
                 irs.copy(calculation = irs.calculation.copy(fixedLegPaymentSchedule = emptySchedule))
@@ -427,7 +426,7 @@ class IRSTests {
     @Test
     fun `ensure failure occurs when no events in floating schedule`() {
         val irs = singleIRS()
-        val emptySchedule = HashMap<LocalDate, FloatingRatePaymentEvent>()
+        val emptySchedule = mutableMapOf<LocalDate, FloatingRatePaymentEvent>()
         transaction {
             output() {
                 irs.copy(calculation = irs.calculation.copy(floatingLegPaymentSchedule = emptySchedule))