timers: clean up for readability

Remove micro-optimizations that no longer yield any benefits,
restructure timers & immediates to be a bit more straightforward.

Adjust timers benchmarks to run long enough to offer meaningful data.

PR-URL: #17279
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Timothy Gu <timothygu99@gmail.com>

benchmark/timers/immediate.js

@@ -2,7 +2,7 @@
 const common = require('../common.js');
 
 const bench = common.createBenchmark(main, {
-  thousands: [2000],
+  thousands: [5000],
   type: ['depth', 'depth1', 'breadth', 'breadth1', 'breadth4', 'clear']
 });
 
@@ -88,6 +88,7 @@ function breadth1(N) {
 
 // concurrent setImmediate, 4 arguments
 function breadth4(N) {
+  N /= 2;
   var n = 0;
   bench.start();
   function cb(a1, a2, a3, a4) {
@@ -101,6 +102,7 @@ function breadth4(N) {
 }
 
 function clear(N) {
+  N *= 4;
   bench.start();
   function cb(a1) {
     if (a1 === 2)

benchmark/timers/set-immediate-breadth-args.js

@@ -19,9 +19,9 @@ function main(conf) {
   bench.start();
   for (let i = 0; i < N; i++) {
     if (i % 3 === 0)
-      setImmediate(cb3, 512, true, null);
+      setImmediate(cb3, 512, true, null, 512, true, null);
     else if (i % 2 === 0)
-      setImmediate(cb2, false, 5.1);
+      setImmediate(cb2, false, 5.1, 512);
     else
       setImmediate(cb1, 0);
   }

benchmark/timers/set-immediate-depth-args.js

@@ -2,7 +2,7 @@
 
 const common = require('../common.js');
 const bench = common.createBenchmark(main, {
-  millions: [10]
+  millions: [5]
 });
 
 function main(conf) {
@@ -15,29 +15,29 @@ function main(conf) {
   function cb3(n, arg2, arg3) {
     if (--n) {
       if (n % 3 === 0)
-        setImmediate(cb3, n, true, null);
+        setImmediate(cb3, n, true, null, 5.1, null, true);
       else if (n % 2 === 0)
-        setImmediate(cb2, n, 5.1);
+        setImmediate(cb2, n, 5.1, true);
       else
         setImmediate(cb1, n);
     }
   }
   function cb2(n, arg2) {
     if (--n) {
       if (n % 3 === 0)
-        setImmediate(cb3, n, true, null);
+        setImmediate(cb3, n, true, null, 5.1, null, true);
       else if (n % 2 === 0)
-        setImmediate(cb2, n, 5.1);
+        setImmediate(cb2, n, 5.1, true);
       else
         setImmediate(cb1, n);
     }
   }
   function cb1(n) {
     if (--n) {
       if (n % 3 === 0)
-        setImmediate(cb3, n, true, null);
+        setImmediate(cb3, n, true, null, 5.1, null, true);
       else if (n % 2 === 0)
-        setImmediate(cb2, n, 5.1);
+        setImmediate(cb2, n, 5.1, true);
       else
         setImmediate(cb1, n);
     }

benchmark/timers/timers-breadth.js

@@ -2,7 +2,7 @@
 const common = require('../common.js');
 
 const bench = common.createBenchmark(main, {
-  thousands: [500],
+  thousands: [5000],
 });
 
 function main(conf) {

benchmark/timers/timers-cancel-pooled.js

@@ -3,11 +3,11 @@ const common = require('../common.js');
 const assert = require('assert');
 
 const bench = common.createBenchmark(main, {
-  thousands: [500],
+  millions: [5],
 });
 
 function main(conf) {
-  const iterations = +conf.thousands * 1e3;
+  const iterations = +conf.millions * 1e6;
 
   var timer = setTimeout(() => {}, 1);
   for (var i = 0; i < iterations; i++) {
@@ -24,7 +24,7 @@ function main(conf) {
     clearTimeout(timer);
   }
 
-  bench.end(iterations / 1e3);
+  bench.end(iterations / 1e6);
 }
 
 function cb() {

benchmark/timers/timers-cancel-unpooled.js

@@ -3,11 +3,11 @@ const common = require('../common.js');
 const assert = require('assert');
 
 const bench = common.createBenchmark(main, {
-  thousands: [100],
+  millions: [1],
 });
 
 function main(conf) {
-  const iterations = +conf.thousands * 1e3;
+  const iterations = +conf.millions * 1e6;
 
   const timersList = [];
   for (var i = 0; i < iterations; i++) {
@@ -18,7 +18,7 @@ function main(conf) {
   for (var j = 0; j < iterations + 1; j++) {
     clearTimeout(timersList[j]);
   }
-  bench.end(iterations / 1e3);
+  bench.end(iterations / 1e6);
 }
 
 function cb() {

benchmark/timers/timers-insert-pooled.js

@@ -2,17 +2,17 @@
 const common = require('../common.js');
 
 const bench = common.createBenchmark(main, {
-  thousands: [500],
+  millions: [5],
 });
 
 function main(conf) {
-  const iterations = +conf.thousands * 1e3;
+  const iterations = +conf.millions * 1e6;
 
   bench.start();
 
   for (var i = 0; i < iterations; i++) {
     setTimeout(() => {}, 1);
   }
 
-  bench.end(iterations / 1e3);
+  bench.end(iterations / 1e6);
 }

benchmark/timers/timers-insert-unpooled.js

@@ -3,19 +3,19 @@ const common = require('../common.js');
 const assert = require('assert');
 
 const bench = common.createBenchmark(main, {
-  thousands: [100],
+  millions: [1],
 });
 
 function main(conf) {
-  const iterations = +conf.thousands * 1e3;
+  const iterations = +conf.millions * 1e6;
 
   const timersList = [];
 
   bench.start();
   for (var i = 0; i < iterations; i++) {
     timersList.push(setTimeout(cb, i + 1));
   }
-  bench.end(iterations / 1e3);
+  bench.end(iterations / 1e6);
 
   for (var j = 0; j < iterations + 1; j++) {
     clearTimeout(timersList[j]);

benchmark/timers/timers-timeout-pooled.js

@@ -1,23 +1,35 @@
 'use strict';
 const common = require('../common.js');
 
+// The following benchmark measures setting up n * 1e6 timeouts,
+// which then get executed on the next uv tick
+
 const bench = common.createBenchmark(main, {
-  thousands: [500],
+  millions: [10],
 });
 
 function main(conf) {
-  const iterations = +conf.thousands * 1e3;
-  var count = 0;
+  const iterations = +conf.millions * 1e6;
+  let count = 0;
 
-  for (var i = 0; i < iterations; i++) {
-    setTimeout(cb, 1);
-  }
-
-  bench.start();
+  // Function tracking on the hidden class in V8 can cause misleading
+  // results in this benchmark if only a single function is used —
+  // alternate between two functions for a fairer benchmark
 
   function cb() {
     count++;
     if (count === iterations)
-      bench.end(iterations / 1e3);
+      bench.end(iterations / 1e6);
   }
+  function cb2() {
+    count++;
+    if (count === iterations)
+      bench.end(iterations / 1e6);
+  }
+
+  for (var i = 0; i < iterations; i++) {
+    setTimeout(i % 2 ? cb : cb2, 1);
+  }
+
+  bench.start();
 }