perf: enable prioritized tasks queue only when necessary

[poolifier.git] / src / priority-queue.ts

diff --git a/src/priority-queue.ts b/src/priority-queue.ts
index ed4d63f5fa9cb03b71f1e91b472f84d1978d2573..ee3310c3d8f2cb8cf6e4d6287d0a668eb20f4a9c 100644 (file)
--- a/src/priority-queue.ts
+++ b/src/priority-queue.ts
@@ -27,27 +27,38 @@ export class PriorityQueue<T> {
   private head!: PriorityQueueNode<T>
   private tail!: PriorityQueueNode<T>
   private readonly bucketSize: number
+  /** The priority queue maximum size. */
   public maxSize!: number
 
   /**
    * Constructs a priority queue.
    *
    * @param bucketSize - Prioritized bucket size. @defaultValue defaultBucketSize
+   * @param enablePriority - Whether to enable priority. @defaultValue false
    * @returns PriorityQueue.
    */
-  public constructor (bucketSize: number = defaultBucketSize) {
+  public constructor (
+    bucketSize: number = defaultBucketSize,
+    enablePriority = false
+  ) {
     if (!Number.isSafeInteger(bucketSize)) {
-      throw new TypeError('bucketSize must be an integer')
+      throw new TypeError(
+        `Invalid bucket size: '${bucketSize}' is not an integer`
+      )
     }
-    if (bucketSize < 1) {
-      throw new RangeError('bucketSize must be greater than or equal to 1')
+    if (bucketSize < 0) {
+      throw new RangeError(`Invalid bucket size: ${bucketSize} < 0`)
     }
     this.bucketSize = bucketSize
-    this.clear()
+    this.head = this.tail = new FixedPriorityQueue(
+      this.bucketSize,
+      enablePriority
+    )
+    this.maxSize = 0
   }
 
   /**
-   * The size of the priority queue.
+   * The priority queue size.
    */
   public get size (): number {
     let node: PriorityQueueNode<T> | undefined = this.tail
@@ -59,6 +70,21 @@ export class PriorityQueue<T> {
     return size
   }
 
+  public get enablePriority (): boolean {
+    return this.head.enablePriority
+  }
+
+  public set enablePriority (enablePriority: boolean) {
+    if (this.head.enablePriority === enablePriority) {
+      return
+    }
+    let node: PriorityQueueNode<T> | undefined = this.tail
+    while (node != null) {
+      node.enablePriority = enablePriority
+      node = node.next
+    }
+  }
+
   /**
    * The number of filled prioritized buckets.
    */
@@ -75,7 +101,10 @@ export class PriorityQueue<T> {
    */
   public enqueue (data: T, priority?: number): number {
     if (this.head.full()) {
-      this.head = this.head.next = new FixedPriorityQueue(this.bucketSize)
+      this.head = this.head.next = new FixedPriorityQueue(
+        this.bucketSize,
+        this.enablePriority
+      )
     }
     this.head.enqueue(data, priority)
     const size = this.size
@@ -93,22 +122,25 @@ export class PriorityQueue<T> {
    */
   public dequeue (bucket?: number): T | undefined {
     let tail: PriorityQueueNode<T> | undefined = this.tail
-    if (bucket != null) {
-      let currentBucket = 0
+    let tailChanged = false
+    if (bucket != null && bucket > 0) {
+      let currentBucket = 1
       while (tail != null) {
-        ++currentBucket
         if (currentBucket === bucket) {
           break
         }
+        ++currentBucket
         tail = tail.next
+        tailChanged = true
       }
     }
     // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
     const data = tail!.dequeue()
     // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
     if (tail!.empty() && tail!.next != null) {
-      if (tail === this.tail) {
-        this.tail = tail.next
+      if (!tailChanged) {
+        // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+        this.tail = tail!.next
       } else {
         let node: PriorityQueueNode<T> | undefined = this.tail
         while (node != null) {
@@ -130,7 +162,10 @@ export class PriorityQueue<T> {
    * Clears the priority queue.
    */
   public clear (): void {
-    this.head = this.tail = new FixedPriorityQueue(this.bucketSize)
+    this.head = this.tail = new FixedPriorityQueue(
+      this.bucketSize,
+      this.enablePriority
+    )
     this.maxSize = 0
   }
 
@@ -141,21 +176,21 @@ export class PriorityQueue<T> {
    * @see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Iteration_protocols
    */
   public [Symbol.iterator] (): Iterator<T> {
-    let i = 0
+    let index = 0
     let node = this.tail
     return {
       next: () => {
-        if (node.empty() || (i >= node.capacity && node.next == null)) {
+        const value = node.get(index) as T
+        if (value == null) {
           return {
             value: undefined,
             done: true
           }
         }
-        const value = node.dequeue() as T
-        ++i
-        if (i === node.capacity && node.next != null) {
+        ++index
+        if (index === node.capacity && node.next != null) {
           node = node.next
-          i = 0
+          index = 0
         }
         return {
           value,