Small perf improvement (5%) in sync mode (#42)

pinojs · Aug 13, 2020 · a299047 · a299047
1 parent d6deb50
commit a299047
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Showing 2 changed files with 11 additions and 2 deletions.
diff --git a/index.js b/index.js
@@ -19,6 +19,7 @@ const MAX_WRITE = 16 * 1024 * 1024
 function openFile (file, sonic) {
   sonic._opening = true
   sonic._writing = true
+  sonic._asyncDrainScheduled = false
   sonic.file = file
 
   // NOTE: 'error' and 'ready' events emitted below only relevant when sonic.sync===false
@@ -164,9 +165,17 @@ function SonicBoom (opts) {
       }
     }
   }
+
+  this.on('newListener', function (name) {
+    if (name === 'drain') {
+      this._asyncDrainScheduled = false
+    }
+  })
 }
 
 function emitDrain (sonic) {
+  const hasListeners = sonic.listenerCount('drain') > 0
+  if (!hasListeners) return
   sonic._asyncDrainScheduled = false
   sonic.emit('drain')
 }

diff --git a/test.js b/test.js
@@ -73,8 +73,6 @@ function buildTests (test, sync) {
     const fd = fs.openSync(dest, 'w')
     const stream = new SonicBoom({ fd, sync })
 
-    t.ok(stream.write('hello world\n'))
-
     stream.once('drain', () => {
       fs.readFile(dest, 'utf8', (err, data) => {
         t.error(err)
@@ -91,6 +89,8 @@ function buildTests (test, sync) {
       })
     })
 
+    t.ok(stream.write('hello world\n'))
+
     stream.on('finish', () => {
       t.pass('finish emitted')
     })