From bb81390db2f5fde6d34e6679cc2145f74d4f19d4 Mon Sep 17 00:00:00 2001
From: zhangzifa <tonyzzf@163.com>
Date: Tue, 29 Aug 2017 17:35:56 +0800
Subject: [PATCH] timers: fix eventloop block
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

When there are at least 2 timers set by setInterval whose callback
execution are longer than interval, the eventloop will be blocked.

This commit fix the above bug.

PR-URL: https://github.com/nodejs/node/pull/15072
Fixes: https://github.com/nodejs/node/issues/15068
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: James M Snell <jasnell@gmail.com>
---
 lib/timers.js                                 |  2 +-
 .../sequential/test-timers-block-eventloop.js | 22 +++++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)
 create mode 100644 test/sequential/test-timers-block-eventloop.js

diff --git a/lib/timers.js b/lib/timers.js
index a612f0ea4a1037..e1d13c38a73047 100644
--- a/lib/timers.js
+++ b/lib/timers.js
@@ -183,7 +183,7 @@ function listOnTimeout() {
     if (diff < msecs) {
       var timeRemaining = msecs - (TimerWrap.now() - timer._idleStart);
       if (timeRemaining < 0) {
-        timeRemaining = 0;
+        timeRemaining = 1;
       }
       this.start(timeRemaining);
       debug('%d list wait because diff is %d', msecs, diff);
diff --git a/test/sequential/test-timers-block-eventloop.js b/test/sequential/test-timers-block-eventloop.js
new file mode 100644
index 00000000000000..210cf0d80a1127
--- /dev/null
+++ b/test/sequential/test-timers-block-eventloop.js
@@ -0,0 +1,22 @@
+'use strict';
+
+const common = require('../common');
+const fs = require('fs');
+
+const t1 = setInterval(() => {
+  common.busyLoop(12);
+}, 10);
+
+const t2 = setInterval(() => {
+  common.busyLoop(15);
+}, 10);
+
+const t3 = setTimeout(common.mustNotCall('eventloop blocked!'), 100);
+
+setTimeout(function() {
+  fs.stat('./nonexistent.txt', (err, stats) => {
+    clearInterval(t1);
+    clearInterval(t2);
+    clearTimeout(t3);
+  });
+}, 50);