docs: improve code documentation

[poolifier.git] / src / utils.ts

diff --git a/src/utils.ts b/src/utils.ts
index 7b921ffa4b94efcfd673b75248e44ee305466058..7ac4ab25db67446a49b2fc42a0f219c043d4af6f 100644 (file)
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -1,4 +1,8 @@
-import type { WorkerChoiceStrategyOptions } from './pools/selection-strategies/selection-strategies-types'
+import os from 'node:os'
+import type {
+  MeasurementStatisticsRequirements,
+  WorkerChoiceStrategyOptions
+} from './pools/selection-strategies/selection-strategies-types'
 
 /**
  * An intentional empty function.
@@ -13,11 +17,41 @@ export const EMPTY_FUNCTION: () => void = Object.freeze(() => {
 export const DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS: WorkerChoiceStrategyOptions =
   {
     runTime: { median: false },
-    waitTime: { median: false }
+    waitTime: { median: false },
+    elu: { median: false }
   }
 
 /**
- * Compute the median of the given data set.
+ * Default measurement statistics requirements.
+ */
+export const DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS: MeasurementStatisticsRequirements =
+  {
+    aggregate: false,
+    average: false,
+    median: false
+  }
+
+/**
+ * Returns safe host OS optimized estimate of the default amount of parallelism a pool should use.
+ * Always returns a value greater than zero.
+ *
+ * @returns The host OS optimized maximum pool size.
+ */
+export const availableParallelism = (): number => {
+  let availableParallelism = 1
+  try {
+    availableParallelism = os.availableParallelism()
+  } catch {
+    const cpus = os.cpus()
+    if (Array.isArray(cpus) && cpus.length > 0) {
+      availableParallelism = cpus.length
+    }
+  }
+  return availableParallelism
+}
+
+/**
+ * Computes the median of the given data set.
  *
  * @param dataSet - Data set.
  * @returns The median of the given data set.
@@ -37,6 +71,19 @@ export const median = (dataSet: number[]): number => {
   )
 }
 
+/**
+ * Rounds the given number to the given scale.
+ * The rounding is done using the "round half away from zero" method.
+ *
+ * @param num - The number to round.
+ * @param scale - The scale to round to.
+ * @returns The rounded number.
+ */
+export const round = (num: number, scale = 2): number => {
+  const rounder = Math.pow(10, scale)
+  return Math.round(num * rounder * (1 + Number.EPSILON)) / rounder
+}
+
 /**
  * Is the given object a plain object?
  *