feat: continuous task stealing
[poolifier.git] / tests / pools / selection-strategies / selection-strategies.test.js
index e9376281efbe66dec0a5f193b03a9fc02bf039fd..77713b6f03f20f8dc883cad07820b292a16d47de 100644 (file)
@@ -1,9 +1,9 @@
 const { expect } = require('expect')
 const {
-  WorkerChoiceStrategies,
   DynamicThreadPool,
+  FixedClusterPool,
   FixedThreadPool,
-  FixedClusterPool
+  WorkerChoiceStrategies
 } = require('../../../lib')
 const { CircularArray } = require('../../../lib/circular-array')
 
@@ -79,7 +79,7 @@ describe('Selection strategies test suite', () => {
         expect(
           pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
             workerChoiceStrategy
-          ).nextWorkerNodeId
+          ).nextWorkerNodeKey
         ).toBe(0)
       } else if (workerChoiceStrategy === WorkerChoiceStrategies.FAIR_SHARE) {
         expect(
@@ -98,7 +98,7 @@ describe('Selection strategies test suite', () => {
         expect(
           pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
             workerChoiceStrategy
-          ).currentWorkerNodeId
+          ).nextWorkerNodeKey
         ).toBe(0)
         expect(
           pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -115,7 +115,33 @@ describe('Selection strategies test suite', () => {
     await pool.destroy()
   })
 
-  it('Verify ROUND_ROBIN strategy default tasks usage statistics requirements', async () => {
+  it('Verify ROUND_ROBIN strategy default policy', async () => {
+    const workerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN
+    let pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      dynamicWorkerUsage: false,
+      dynamicWorkerReady: true
+    })
+    await pool.destroy()
+    pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      dynamicWorkerUsage: false,
+      dynamicWorkerReady: true
+    })
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify ROUND_ROBIN strategy default tasks statistics requirements', async () => {
     const workerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN
     let pool = new FixedThreadPool(
       max,
@@ -185,46 +211,35 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toStrictEqual({
         tasks: {
           executed: maxMultiplier,
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
         runTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: 0
+          }
         }
       })
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         WorkerChoiceStrategies.ROUND_ROBIN
-      ).nextWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBe(0)
     // We need to clean up the resources after our test
     await pool.destroy()
@@ -245,46 +260,39 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toStrictEqual({
         tasks: {
-          executed: maxMultiplier,
+          executed: expect.any(Number),
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
         runTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: 0
+          }
         }
       })
+      expect(workerNode.usage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.usage.tasks.executed).toBeLessThanOrEqual(
+        max * maxMultiplier
+      )
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         WorkerChoiceStrategies.ROUND_ROBIN
-      ).nextWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBe(0)
     // We need to clean up the resources after our test
     await pool.destroy()
@@ -326,13 +334,13 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).nextWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBeDefined()
     pool.setWorkerChoiceStrategy(workerChoiceStrategy)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).nextWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBe(0)
     await pool.destroy()
     pool = new DynamicThreadPool(
@@ -344,19 +352,45 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).nextWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBeDefined()
     pool.setWorkerChoiceStrategy(workerChoiceStrategy)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).nextWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBe(0)
     // We need to clean up the resources after our test
     await pool.destroy()
   })
 
-  it('Verify LEAST_USED strategy default tasks usage statistics requirements', async () => {
+  it('Verify LEAST_USED strategy default policy', async () => {
+    const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_USED
+    let pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      dynamicWorkerUsage: false,
+      dynamicWorkerReady: true
+    })
+    await pool.destroy()
+    pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      dynamicWorkerUsage: false,
+      dynamicWorkerReady: true
+    })
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify LEAST_USED strategy default tasks statistics requirements', async () => {
     const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_USED
     let pool = new FixedThreadPool(
       max,
@@ -426,41 +460,34 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toStrictEqual({
         tasks: {
-          executed: maxMultiplier,
+          executed: expect.any(Number),
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
         runTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: 0
+          }
         }
       })
+      expect(workerNode.usage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.usage.tasks.executed).toBeLessThanOrEqual(
+        max * maxMultiplier
+      )
     }
     // We need to clean up the resources after our test
     await pool.destroy()
@@ -481,47 +508,66 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toStrictEqual({
         tasks: {
-          executed: maxMultiplier,
+          executed: expect.any(Number),
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
         runTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: 0
+          }
         }
       })
+      expect(workerNode.usage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.usage.tasks.executed).toBeLessThanOrEqual(
+        max * maxMultiplier
+      )
     }
     // We need to clean up the resources after our test
     await pool.destroy()
   })
 
-  it('Verify LEAST_BUSY strategy default tasks usage statistics requirements', async () => {
+  it('Verify LEAST_BUSY strategy default policy', async () => {
+    const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_BUSY
+    let pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      dynamicWorkerUsage: false,
+      dynamicWorkerReady: true
+    })
+    await pool.destroy()
+    pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      dynamicWorkerUsage: false,
+      dynamicWorkerReady: true
+    })
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify LEAST_BUSY strategy default tasks statistics requirements', async () => {
     const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_BUSY
     let pool = new FixedThreadPool(
       max,
@@ -591,49 +637,44 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toMatchObject({
         tasks: {
           executed: expect.any(Number),
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
         runTime: {
-          aggregate: expect.any(Number),
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregate: expect.any(Number),
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: 0
+          }
         }
       })
-      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
-      expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
+      expect(workerNode.usage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.usage.tasks.executed).toBeLessThanOrEqual(
         max * maxMultiplier
       )
-      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThanOrEqual(0)
-      expect(workerNode.workerUsage.waitTime.aggregate).toBeGreaterThanOrEqual(
-        0
-      )
+      if (workerNode.usage.runTime.aggregate == null) {
+        expect(workerNode.usage.runTime.aggregate).toBeUndefined()
+      } else {
+        expect(workerNode.usage.runTime.aggregate).toBeGreaterThan(0)
+      }
+      if (workerNode.usage.waitTime.aggregate == null) {
+        expect(workerNode.usage.waitTime.aggregate).toBeUndefined()
+      } else {
+        expect(workerNode.usage.waitTime.aggregate).toBeGreaterThan(0)
+      }
     }
     // We need to clean up the resources after our test
     await pool.destroy()
@@ -654,53 +695,76 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toMatchObject({
         tasks: {
           executed: expect.any(Number),
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
         runTime: {
-          aggregate: expect.any(Number),
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregate: expect.any(Number),
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: 0
+          }
         }
       })
-      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThan(0)
-      expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
+      expect(workerNode.usage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.usage.tasks.executed).toBeLessThanOrEqual(
         max * maxMultiplier
       )
-      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThan(0)
-      expect(workerNode.workerUsage.waitTime.aggregate).toBeGreaterThan(0)
+      if (workerNode.usage.runTime.aggregate == null) {
+        expect(workerNode.usage.runTime.aggregate).toBeUndefined()
+      } else {
+        expect(workerNode.usage.runTime.aggregate).toBeGreaterThan(0)
+      }
+      if (workerNode.usage.waitTime.aggregate == null) {
+        expect(workerNode.usage.waitTime.aggregate).toBeUndefined()
+      } else {
+        expect(workerNode.usage.waitTime.aggregate).toBeGreaterThan(0)
+      }
     }
     // We need to clean up the resources after our test
     await pool.destroy()
   })
 
-  it('Verify LEAST_ELU strategy default tasks usage statistics requirements', async () => {
+  it('Verify LEAST_ELU strategy default policy', async () => {
+    const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_ELU
+    let pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      dynamicWorkerUsage: false,
+      dynamicWorkerReady: true
+    })
+    await pool.destroy()
+    pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      dynamicWorkerUsage: false,
+      dynamicWorkerReady: true
+    })
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify LEAST_ELU strategy default tasks statistics requirements', async () => {
     const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_ELU
     let pool = new FixedThreadPool(
       max,
@@ -770,47 +834,40 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toMatchObject({
         tasks: {
           executed: expect.any(Number),
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
         runTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: expect.any(Number),
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: expect.any(Number)
+          }
         }
       })
-      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
-      expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
+      expect(workerNode.usage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.usage.tasks.executed).toBeLessThanOrEqual(
         max * maxMultiplier
       )
-      expect(workerNode.workerUsage.elu.utilization).toBeGreaterThanOrEqual(0)
-      expect(workerNode.workerUsage.elu.utilization).toBeLessThanOrEqual(1)
+      if (workerNode.usage.elu.utilization == null) {
+        expect(workerNode.usage.elu.utilization).toBeUndefined()
+      } else {
+        expect(workerNode.usage.elu.utilization).toBeGreaterThanOrEqual(0)
+        expect(workerNode.usage.elu.utilization).toBeLessThanOrEqual(1)
+      }
     }
     // We need to clean up the resources after our test
     await pool.destroy()
@@ -831,53 +888,72 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toMatchObject({
         tasks: {
           executed: expect.any(Number),
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
         runTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: expect.any(Number),
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: expect.any(Number)
+          }
         }
       })
-      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
-      expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
+      expect(workerNode.usage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.usage.tasks.executed).toBeLessThanOrEqual(
         max * maxMultiplier
       )
-      expect(workerNode.workerUsage.elu.utilization).toBeGreaterThanOrEqual(0)
-      expect(workerNode.workerUsage.elu.utilization).toBeLessThanOrEqual(1)
+      if (workerNode.usage.elu.utilization == null) {
+        expect(workerNode.usage.elu.utilization).toBeUndefined()
+      } else {
+        expect(workerNode.usage.elu.utilization).toBeGreaterThanOrEqual(0)
+        expect(workerNode.usage.elu.utilization).toBeLessThanOrEqual(1)
+      }
     }
     // We need to clean up the resources after our test
     await pool.destroy()
   })
 
-  it('Verify FAIR_SHARE strategy default tasks usage statistics requirements', async () => {
+  it('Verify FAIR_SHARE strategy default policy', async () => {
+    const workerChoiceStrategy = WorkerChoiceStrategies.FAIR_SHARE
+    let pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      dynamicWorkerUsage: false,
+      dynamicWorkerReady: true
+    })
+    await pool.destroy()
+    pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      dynamicWorkerUsage: false,
+      dynamicWorkerReady: true
+    })
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify FAIR_SHARE strategy default tasks statistics requirements', async () => {
     const workerChoiceStrategy = WorkerChoiceStrategies.FAIR_SHARE
     let pool = new FixedThreadPool(
       max,
@@ -947,45 +1023,50 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toMatchObject({
         tasks: {
-          executed: maxMultiplier,
+          executed: expect.any(Number),
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
         runTime: {
-          aggregate: expect.any(Number),
-          average: expect.any(Number),
-          median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: expect.any(Number),
-            average: expect.any(Number),
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: expect.any(Number)
+          }
         }
       })
-      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThan(0)
-      expect(workerNode.workerUsage.runTime.average).toBeGreaterThan(0)
-      expect(workerNode.workerUsage.elu.utilization).toBeGreaterThanOrEqual(0)
-      expect(workerNode.workerUsage.elu.utilization).toBeLessThanOrEqual(1)
+      expect(workerNode.usage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.usage.tasks.executed).toBeLessThanOrEqual(
+        max * maxMultiplier
+      )
+      if (workerNode.usage.runTime.aggregate == null) {
+        expect(workerNode.usage.runTime.aggregate).toBeUndefined()
+      } else {
+        expect(workerNode.usage.runTime.aggregate).toBeGreaterThan(0)
+      }
+      if (workerNode.usage.runTime.average == null) {
+        expect(workerNode.usage.runTime.average).toBeUndefined()
+      } else {
+        expect(workerNode.usage.runTime.average).toBeGreaterThan(0)
+      }
+      if (workerNode.usage.elu.utilization == null) {
+        expect(workerNode.usage.elu.utilization).toBeUndefined()
+      } else {
+        expect(workerNode.usage.elu.utilization).toBeGreaterThanOrEqual(0)
+        expect(workerNode.usage.elu.utilization).toBeLessThanOrEqual(1)
+      }
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1011,45 +1092,50 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toMatchObject({
         tasks: {
-          executed: maxMultiplier,
+          executed: expect.any(Number),
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
         runTime: {
-          aggregate: expect.any(Number),
-          average: expect.any(Number),
-          median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: expect.any(Number),
-            average: expect.any(Number),
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: expect.any(Number)
+          }
         }
       })
-      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThan(0)
-      expect(workerNode.workerUsage.runTime.average).toBeGreaterThan(0)
-      expect(workerNode.workerUsage.elu.utilization).toBeGreaterThanOrEqual(0)
-      expect(workerNode.workerUsage.elu.utilization).toBeLessThanOrEqual(1)
+      expect(workerNode.usage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.usage.tasks.executed).toBeLessThanOrEqual(
+        max * maxMultiplier
+      )
+      if (workerNode.usage.runTime.aggregate == null) {
+        expect(workerNode.usage.runTime.aggregate).toBeUndefined()
+      } else {
+        expect(workerNode.usage.runTime.aggregate).toBeGreaterThan(0)
+      }
+      if (workerNode.usage.runTime.average == null) {
+        expect(workerNode.usage.runTime.average).toBeUndefined()
+      } else {
+        expect(workerNode.usage.runTime.average).toBeGreaterThan(0)
+      }
+      if (workerNode.usage.elu.utilization == null) {
+        expect(workerNode.usage.elu.utilization).toBeUndefined()
+      } else {
+        expect(workerNode.usage.elu.utilization).toBeGreaterThanOrEqual(0)
+        expect(workerNode.usage.elu.utilization).toBeLessThanOrEqual(1)
+      }
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1080,45 +1166,50 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toMatchObject({
         tasks: {
-          executed: maxMultiplier,
+          executed: expect.any(Number),
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
         runTime: {
-          aggregate: expect.any(Number),
-          average: 0,
-          median: expect.any(Number),
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: expect.any(Number),
-            average: expect.any(Number),
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: expect.any(Number)
+          }
         }
       })
-      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThan(0)
-      expect(workerNode.workerUsage.runTime.median).toBeGreaterThan(0)
-      expect(workerNode.workerUsage.elu.utilization).toBeGreaterThanOrEqual(0)
-      expect(workerNode.workerUsage.elu.utilization).toBeLessThanOrEqual(1)
+      expect(workerNode.usage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.usage.tasks.executed).toBeLessThanOrEqual(
+        max * maxMultiplier
+      )
+      if (workerNode.usage.runTime.aggregate == null) {
+        expect(workerNode.usage.runTime.aggregate).toBeUndefined()
+      } else {
+        expect(workerNode.usage.runTime.aggregate).toBeGreaterThan(0)
+      }
+      if (workerNode.usage.runTime.median == null) {
+        expect(workerNode.usage.runTime.median).toBeUndefined()
+      } else {
+        expect(workerNode.usage.runTime.median).toBeGreaterThan(0)
+      }
+      if (workerNode.usage.elu.utilization == null) {
+        expect(workerNode.usage.elu.utilization).toBeUndefined()
+      } else {
+        expect(workerNode.usage.elu.utilization).toBeGreaterThanOrEqual(0)
+        expect(workerNode.usage.elu.utilization).toBeLessThanOrEqual(1)
+      }
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1203,7 +1294,33 @@ describe('Selection strategies test suite', () => {
     await pool.destroy()
   })
 
-  it('Verify WEIGHTED_ROUND_ROBIN strategy default tasks usage statistics requirements', async () => {
+  it('Verify WEIGHTED_ROUND_ROBIN strategy default policy', async () => {
+    const workerChoiceStrategy = WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN
+    let pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      dynamicWorkerUsage: false,
+      dynamicWorkerReady: true
+    })
+    await pool.destroy()
+    pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      dynamicWorkerUsage: false,
+      dynamicWorkerReady: true
+    })
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify WEIGHTED_ROUND_ROBIN strategy default tasks statistics requirements', async () => {
     const workerChoiceStrategy = WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN
     let pool = new FixedThreadPool(
       max,
@@ -1273,47 +1390,44 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toStrictEqual({
         tasks: {
           executed: expect.any(Number),
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
-        runTime: {
-          aggregate: expect.any(Number),
-          average: expect.any(Number),
-          median: 0,
+        runTime: expect.objectContaining({
           history: expect.any(CircularArray)
-        },
+        }),
         waitTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: 0
+          }
         }
       })
-      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThanOrEqual(0)
-      expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
+      expect(workerNode.usage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.usage.tasks.executed).toBeLessThanOrEqual(
         max * maxMultiplier
       )
-      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThanOrEqual(0)
-      expect(workerNode.workerUsage.runTime.average).toBeGreaterThanOrEqual(0)
+      if (workerNode.usage.runTime.aggregate == null) {
+        expect(workerNode.usage.runTime.aggregate).toBeUndefined()
+      } else {
+        expect(workerNode.usage.runTime.aggregate).toBeGreaterThan(0)
+      }
+      if (workerNode.usage.runTime.average == null) {
+        expect(workerNode.usage.runTime.average).toBeUndefined()
+      } else {
+        expect(workerNode.usage.runTime.average).toBeGreaterThan(0)
+      }
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1344,47 +1458,44 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toStrictEqual({
         tasks: {
           executed: expect.any(Number),
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
-        runTime: {
-          aggregate: expect.any(Number),
-          average: expect.any(Number),
-          median: 0,
+        runTime: expect.objectContaining({
           history: expect.any(CircularArray)
-        },
+        }),
         waitTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: 0
+          }
         }
       })
-      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThan(0)
-      expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
+      expect(workerNode.usage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.usage.tasks.executed).toBeLessThanOrEqual(
         max * maxMultiplier
       )
-      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThan(0)
-      expect(workerNode.workerUsage.runTime.average).toBeGreaterThan(0)
+      if (workerNode.usage.runTime.aggregate == null) {
+        expect(workerNode.usage.runTime.aggregate).toBeUndefined()
+      } else {
+        expect(workerNode.usage.runTime.aggregate).toBeGreaterThan(0)
+      }
+      if (workerNode.usage.runTime.average == null) {
+        expect(workerNode.usage.runTime.average).toBeUndefined()
+      } else {
+        expect(workerNode.usage.runTime.average).toBeGreaterThan(0)
+      }
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1420,47 +1531,44 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toStrictEqual({
         tasks: {
           executed: expect.any(Number),
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
-        runTime: {
-          aggregate: expect.any(Number),
-          average: 0,
-          median: expect.any(Number),
+        runTime: expect.objectContaining({
           history: expect.any(CircularArray)
-        },
+        }),
         waitTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: 0
+          }
         }
       })
-      expect(workerNode.workerUsage.tasks.executed).toBeGreaterThan(0)
-      expect(workerNode.workerUsage.tasks.executed).toBeLessThanOrEqual(
+      expect(workerNode.usage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.usage.tasks.executed).toBeLessThanOrEqual(
         max * maxMultiplier
       )
-      expect(workerNode.workerUsage.runTime.aggregate).toBeGreaterThan(0)
-      expect(workerNode.workerUsage.runTime.median).toBeGreaterThan(0)
+      if (workerNode.usage.runTime.aggregate == null) {
+        expect(workerNode.usage.runTime.aggregate).toBeUndefined()
+      } else {
+        expect(workerNode.usage.runTime.aggregate).toBeGreaterThan(0)
+      }
+      if (workerNode.usage.runTime.median == null) {
+        expect(workerNode.usage.runTime.median).toBeUndefined()
+      } else {
+        expect(workerNode.usage.runTime.median).toBeGreaterThan(0)
+      }
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1485,7 +1593,7 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBeDefined()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1501,7 +1609,7 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1522,7 +1630,7 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBeDefined()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1538,7 +1646,7 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1554,7 +1662,34 @@ describe('Selection strategies test suite', () => {
     await pool.destroy()
   })
 
-  it('Verify INTERLEAVED_WEIGHTED_ROUND_ROBIN strategy default tasks usage statistics requirements', async () => {
+  it('Verify INTERLEAVED_WEIGHTED_ROUND_ROBIN strategy default policy', async () => {
+    const workerChoiceStrategy =
+      WorkerChoiceStrategies.INTERLEAVED_WEIGHTED_ROUND_ROBIN
+    let pool = new FixedThreadPool(
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      dynamicWorkerUsage: false,
+      dynamicWorkerReady: true
+    })
+    await pool.destroy()
+    pool = new DynamicThreadPool(
+      min,
+      max,
+      './tests/worker-files/thread/testWorker.js',
+      { workerChoiceStrategy }
+    )
+    expect(pool.workerChoiceStrategyContext.getStrategyPolicy()).toStrictEqual({
+      dynamicWorkerUsage: false,
+      dynamicWorkerReady: true
+    })
+    // We need to clean up the resources after our test
+    await pool.destroy()
+  })
+
+  it('Verify INTERLEAVED_WEIGHTED_ROUND_ROBIN strategy default tasks statistics requirements', async () => {
     const workerChoiceStrategy =
       WorkerChoiceStrategies.INTERLEAVED_WEIGHTED_ROUND_ROBIN
     let pool = new FixedThreadPool(
@@ -1628,39 +1763,28 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toStrictEqual({
         tasks: {
           executed: maxMultiplier,
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
         runTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: 0
+          }
         }
       })
     }
@@ -1672,12 +1796,12 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentRoundId
+      ).roundId
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1710,41 +1834,34 @@ describe('Selection strategies test suite', () => {
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.workerUsage).toStrictEqual({
+      expect(workerNode.usage).toStrictEqual({
         tasks: {
-          executed: maxMultiplier,
+          executed: expect.any(Number),
           executing: 0,
           queued: 0,
+          maxQueued: 0,
+          stolen: 0,
           failed: 0
         },
         runTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         waitTime: {
-          aggregate: 0,
-          average: 0,
-          median: 0,
           history: expect.any(CircularArray)
         },
         elu: {
           idle: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
           },
           active: {
-            aggregate: 0,
-            average: 0,
-            median: 0,
             history: expect.any(CircularArray)
-          },
-          utilization: 0
+          }
         }
       })
+      expect(workerNode.usage.tasks.executed).toBeGreaterThanOrEqual(0)
+      expect(workerNode.usage.tasks.executed).toBeLessThanOrEqual(
+        max * maxMultiplier
+      )
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1754,12 +1871,12 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentRoundId
+      ).roundId
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1784,12 +1901,12 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentRoundId
+      ).roundId
     ).toBeDefined()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBeDefined()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1805,12 +1922,12 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentRoundId
+      ).roundId
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1835,12 +1952,12 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentRoundId
+      ).roundId
     ).toBeDefined()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBeDefined()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -1856,7 +1973,7 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).currentWorkerNodeId
+      ).nextWorkerNodeKey
     ).toBe(0)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(