diff --git a/tile/base/chrono.cc b/tile/base/chrono.cc
index f0c6a45..1cba8f4 100644
--- a/tile/base/chrono.cc
+++ b/tile/base/chrono.cc
@@ -90,7 +90,8 @@ void CoarseClockInitializer::Start() {
     while (running_.load(std::memory_order_relaxed)) {
       // std::this_thread::sleep_for(std::chrono::nanoseconds(500));
       UpdateCoarseTimestamps();
-      Sleep(accuracy_as_ns / 2);
+      // Sleep(accuracy_as_ns / 2);
+      std::this_thread::sleep_for(kAccuracy / 2);
     }
   });
 }
diff --git a/tile/base/chrono.h b/tile/base/chrono.h
index 00599b1..7107782 100644
--- a/tile/base/chrono.h
+++ b/tile/base/chrono.h
@@ -17,7 +17,7 @@ namespace chrono {
 
 class CoarseClockInitializer {
 public:
-  static constexpr auto kAccuracy = std::chrono::microseconds(100);
+  static constexpr auto kAccuracy = std::chrono::microseconds(500);
   static CoarseClockInitializer *Instance();
 
   // for `tile::Start()`
diff --git a/tile/base/chrono_test.cc b/tile/base/chrono_test.cc
index be71bf0..8df941c 100644
--- a/tile/base/chrono_test.cc
+++ b/tile/base/chrono_test.cc
@@ -4,7 +4,7 @@
 
 namespace tile {
 
-static constexpr auto one = detail::chrono::CoarseClockInitializer::kAccuracy;
+static constexpr auto one_ms = std::chrono::milliseconds(1);
 
 long AvageTime(std::function<long()> f, std::size_t n = 100) {
   long double total = 0;
@@ -17,28 +17,30 @@ long AvageTime(std::function<long()> f, std::size_t n = 100) {
 
 TEST(SystemClock, Compare) {
   auto diff = AvageTime([] {
-    return (ReadSystemClock() - std::chrono::system_clock::now()) / one;
+    return (ReadSystemClock() - std::chrono::system_clock::now()) / one_ms;
   });
   ASSERT_NEAR(diff, 0, 5);
 }
 
 TEST(SteadyClock, Compare) {
   auto diff = AvageTime([] {
-    return (ReadSteadyClock() - std::chrono::steady_clock::now()) / one;
+    return (ReadSteadyClock() - std::chrono::steady_clock::now()) / one_ms;
   });
   ASSERT_NEAR(diff, 0, 5);
 }
 
 TEST(CoarseSystemClock, Compare) {
   auto diff = AvageTime([] {
-    return (ReadCoarseSystemClock() - std::chrono::system_clock::now()) / one;
+    return (ReadCoarseSystemClock() - std::chrono::system_clock::now()) /
+           one_ms;
   });
   ASSERT_NEAR(diff, 0, 50);
 }
 
 TEST(CoarseSteadyClock, Compare) {
   auto diff = AvageTime([] {
-    return (ReadCoarseSteadyClock() - std::chrono::steady_clock::now()) / one;
+    return (ReadCoarseSteadyClock() - std::chrono::steady_clock::now()) /
+           one_ms;
   });
   ASSERT_NEAR(diff, 0, 50);
 }
diff --git a/tile/base/object_pool/thread_local_test.cc b/tile/base/object_pool/thread_local_test.cc
index 09aa8cf..c504032 100644
--- a/tile/base/object_pool/thread_local_test.cc
+++ b/tile/base/object_pool/thread_local_test.cc
@@ -61,6 +61,7 @@ static void BusySleep(std::chrono::duration<Rep, Period> dur) {
 namespace object_pool {
 
 TEST(ThreadLocalPool, All) {
+  auto start = ReadCoarseSteadyClock();
   // create 1000 unref objects;
   ASSERT_EQ(alive, 0);
   {
@@ -76,13 +77,17 @@ TEST(ThreadLocalPool, All) {
     BusySleep(std::chrono::milliseconds(10));
     Get<C>().Reset(); // Trigger wash out if possible.
   }
-  ASSERT_EQ(PoolTraits<C>::kHighWaterMark + PoolTraits<C>::kLowWaterMark,
-            alive); // High-water mark.
+  if ((ReadCoarseSteadyClock() - start) < PoolTraits<C>::kMaxIdle) {
+    ASSERT_EQ(PoolTraits<C>::kHighWaterMark + PoolTraits<C>::kLowWaterMark,
+              alive); // High-water mark.
+  }
 
   // Max idle not reached. No effect.
   Get<C>().Reset();
-  ASSERT_EQ(PoolTraits<C>::kHighWaterMark + PoolTraits<C>::kLowWaterMark,
-            alive);
+  if ((ReadCoarseSteadyClock() - start) < PoolTraits<C>::kMaxIdle) {
+    ASSERT_EQ(PoolTraits<C>::kHighWaterMark + PoolTraits<C>::kLowWaterMark,
+              alive);
+  }
 
   BusySleep(std::chrono::milliseconds(5000));
   // std::this_thread::sleep_for(std::chrono::milliseconds(5000));