diff --git a/src/threadpool.c b/src/threadpool.c
index dd0abd9a..15d71994 100644
--- a/src/threadpool.c
+++ b/src/threadpool.c
@@ -44,6 +44,7 @@ static void uv__req_init(uv_loop_t* loop,
 static uv_once_t once = UV_ONCE_INIT;
 static uv_cond_t cond;
 static uv_mutex_t mutex;
+static unsigned int idle_threads;
 static unsigned int nthreads;
 static uv_thread_t* threads;
 static uv_thread_t default_threads[4];
@@ -69,8 +70,11 @@ static void worker(void* arg) {
   for (;;) {
     uv_mutex_lock(&mutex);
 
-    while (QUEUE_EMPTY(&wq))
+    while (QUEUE_EMPTY(&wq)) {
+      idle_threads += 1;
       uv_cond_wait(&cond, &mutex);
+      idle_threads -= 1;
+    }
 
     q = QUEUE_HEAD(&wq);
 
@@ -101,11 +105,9 @@ static void worker(void* arg) {
 
 
 static void post(QUEUE* q) {
-  int empty_queue;
   uv_mutex_lock(&mutex);
-  empty_queue = QUEUE_EMPTY(&wq);
   QUEUE_INSERT_TAIL(&wq, q);
-  if (empty_queue)
+  if (idle_threads > 0)
     uv_cond_signal(&cond);
   uv_mutex_unlock(&mutex);
 }