replaced inMemory cache with caffeine for performance benchmarks

rbcs-cli/native-image/reflect-config.json

@@ -43,6 +43,46 @@
 {
   "name":"com.aayushatharva.brotli4j.Brotli4jLoader"
 },
+{
+  "name":"com.github.benmanes.caffeine.cache.BLCHeader$DrainStatusRef",
+  "fields":[{"name":"drainStatus"}]
+},
+{
+  "name":"com.github.benmanes.caffeine.cache.BaseMpscLinkedArrayQueueColdProducerFields",
+  "fields":[{"name":"producerLimit"}]
+},
+{
+  "name":"com.github.benmanes.caffeine.cache.BaseMpscLinkedArrayQueueConsumerFields",
+  "fields":[{"name":"consumerIndex"}]
+},
+{
+  "name":"com.github.benmanes.caffeine.cache.BaseMpscLinkedArrayQueueProducerFields",
+  "fields":[{"name":"producerIndex"}]
+},
+{
+  "name":"com.github.benmanes.caffeine.cache.BoundedLocalCache",
+  "fields":[{"name":"refreshes"}]
+},
+{
+  "name":"com.github.benmanes.caffeine.cache.PS",
+  "fields":[{"name":"key"}, {"name":"value"}]
+},
+{
+  "name":"com.github.benmanes.caffeine.cache.PSW",
+  "fields":[{"name":"writeTime"}]
+},
+{
+  "name":"com.github.benmanes.caffeine.cache.PSWMS",
+  "methods":[{"name":"<init>","parameterTypes":[] }]
+},
+{
+  "name":"com.github.benmanes.caffeine.cache.SSMSW",
+  "fields":[{"name":"FACTORY"}]
+},
+{
+  "name":"com.github.benmanes.caffeine.cache.StripedBuffer",
+  "fields":[{"name":"tableBusy"}]
+},
 {
   "name":"com.github.luben.zstd.Zstd"
 },
@@ -588,6 +628,9 @@
   "name":"net.woggioni.rbcs.server.exception.ExceptionHandler",
   "methods":[{"name":"exceptionCaught","parameterTypes":["io.netty.channel.ChannelHandlerContext","java.lang.Throwable"] }]
 },
+{
+  "name":"net.woggioni.rbcs.server.handler.BlackHoleRequestHandler"
+},
 {
   "name":"net.woggioni.rbcs.server.handler.MaxRequestSizeHandler",
   "methods":[{"name":"channelRead","parameterTypes":["io.netty.channel.ChannelHandlerContext","java.lang.Object"] }]

rbcs-server/build.gradle

@@ -12,6 +12,7 @@ dependencies {
     implementation catalog.netty.handler
     implementation catalog.netty.buffer
     implementation catalog.netty.transport
+    implementation("com.github.ben-manes.caffeine:caffeine:3.2.0")
 
     api project(':rbcs-common')
     api project(':rbcs-api')

rbcs-server/src/main/java/module-info.java

@@ -18,6 +18,7 @@ module net.woggioni.rbcs.server {
     requires net.woggioni.jwo;
     requires net.woggioni.rbcs.common;
     requires net.woggioni.rbcs.api;
+    requires com.github.benmanes.caffeine;
 
     exports net.woggioni.rbcs.server;
 

rbcs-server/src/main/kotlin/net/woggioni/rbcs/server/cache/InMemoryCache.kt

@@ -1,16 +1,13 @@
 package net.woggioni.rbcs.server.cache
 
+import com.github.benmanes.caffeine.cache.Cache
+import com.github.benmanes.caffeine.cache.Caffeine
 import io.netty.buffer.ByteBuf
 import net.woggioni.rbcs.api.AsyncCloseable
 import net.woggioni.rbcs.api.CacheValueMetadata
 import net.woggioni.rbcs.common.createLogger
 import java.time.Duration
-import java.time.Instant
-import java.util.PriorityQueue
 import java.util.concurrent.CompletableFuture
-import java.util.concurrent.TimeUnit
-import java.util.concurrent.locks.ReentrantReadWriteLock
-import kotlin.concurrent.withLock
 
 private class CacheKey(private val value: ByteArray) {
     override fun equals(other: Any?) = if (other is CacheKey) {
@@ -26,118 +23,29 @@ class CacheEntry(
 )
 
 class InMemoryCache(
-    private val maxAge: Duration,
-    private val maxSize: Long
+    maxAge: Duration,
+    maxSize: Long
 ) : AsyncCloseable {
 
     companion object {
         private val log = createLogger<InMemoryCache>()
     }
 
-    private var mapSize : Long = 0
-    private val map = HashMap<CacheKey, CacheEntry>()
-    private val lock = ReentrantReadWriteLock()
-    private val cond = lock.writeLock().newCondition()
+    private val cache: Cache<CacheKey, CacheEntry> = Caffeine.newBuilder()
+        .expireAfterWrite(maxAge)
+        .maximumSize(maxSize)
+        .build()
+    override fun asyncClose(): CompletableFuture<Void> = CompletableFuture.completedFuture(null)
 
-    private class RemovalQueueElement(val key: CacheKey, val value: CacheEntry, val expiry: Instant) :
-        Comparable<RemovalQueueElement> {
-        override fun compareTo(other: RemovalQueueElement) = expiry.compareTo(other.expiry)
-    }
-
-    private val removalQueue = PriorityQueue<RemovalQueueElement>()
-
-    @Volatile
-    private var running = true
-
-    private val closeFuture = object : CompletableFuture<Void>() {
-        init {
-            Thread.ofVirtual().name("in-memory-cache-gc").start {
-                try {
-                    lock.writeLock().withLock {
-                        while (running) {
-                            val el = removalQueue.poll()
-                            if(el == null) {
-                                cond.await(1000, TimeUnit.MILLISECONDS)
-                                continue
-                            }
-                            val value = el.value
-                            val now = Instant.now()
-                            if (now > el.expiry) {
-                                val removed = map.remove(el.key, value)
-                                if (removed) {
-                                    updateSizeAfterRemoval(value.content)
-                                    //Decrease the reference count for map
-                                    value.content.release()
-                                }
-                            } else {
-                                removalQueue.offer(el)
-                                val interval = minOf(Duration.between(now, el.expiry), Duration.ofSeconds(1))
-                                cond.await(interval.toMillis(), TimeUnit.MILLISECONDS)
-                            }
-                        }
-                        map.forEach {
-                            it.value.content.release()
-                        }
-                        map.clear()
-                    }
-                    complete(null)
-                } catch (ex: Throwable) {
-                    completeExceptionally(ex)
-                }
-            }
-        }
-    }
-
-    fun removeEldest(): Long {
-        while (true) {
-            val el = removalQueue.poll() ?: return mapSize
-            val value = el.value
-            val removed = map.remove(el.key, value)
-            if (removed) {
-                val newSize = updateSizeAfterRemoval(value.content)
-                //Decrease the reference count for map
-                value.content.release()
-                return newSize
-            }
-        }
-    }
-
-    private fun updateSizeAfterRemoval(removed: ByteBuf): Long {
-        mapSize -= removed.readableBytes()
-        return mapSize
-    }
-
-    override fun asyncClose() : CompletableFuture<Void> {
-        running = false
-        lock.writeLock().withLock {
-            cond.signal()
-        }
-        return closeFuture
-    }
-
-    fun get(key: ByteArray) = lock.readLock().withLock {
-        map[CacheKey(key)]?.run {
+    fun get(key: ByteArray) = cache.getIfPresent(CacheKey(key))?.run {
             CacheEntry(metadata, content.retainedDuplicate())
         }
-    }
 
     fun put(
         key: ByteArray,
         value: CacheEntry,
     ) {
         val cacheKey = CacheKey(key)
-        lock.writeLock().withLock {
-            val oldSize = map.put(cacheKey, value)?.let { old ->
-                val result = old.content.readableBytes()
-                old.content.release()
-                result
-            } ?: 0
-            val delta = value.content.readableBytes() - oldSize
-            mapSize += delta
-            removalQueue.offer(RemovalQueueElement(cacheKey, value, Instant.now().plus(maxAge)))
-            while (mapSize > maxSize) {
-                removeEldest()
-            }
-        }
+        cache.put(cacheKey, value)
     }
 }