diff --git a/Changelog.md b/Changelog.md
--- a/Changelog.md
+++ b/Changelog.md
@@ -1,3 +1,7 @@
+### 0.9.1.0
+
+- Do not write into service event channel when Nginx is exiting.
+
 ### 0.9.0.0
 
 - Using interruptible FFI for safeWaitToSetLock to re-enable graceful shutdown
diff --git a/NgxExport.hs b/NgxExport.hs
--- a/NgxExport.hs
+++ b/NgxExport.hs
@@ -389,9 +389,15 @@
     pokeCStringLen x l p pl
     return 1
 
-safeYYHandler :: IO (L.ByteString, CUInt) -> IO (L.ByteString, CUInt)
+safeYYHandler :: IO (L.ByteString, (CUInt, Bool)) ->
+    IO (L.ByteString, (CUInt, Bool))
 safeYYHandler = handle $ \e ->
-    return (C8L.pack $ show (e :: SomeException), 1)
+    return (C8L.pack $ show e,
+            (1, case asyncExceptionFromException e of
+                    Nothing -> False
+                    Just ae -> ae == ThreadKilled
+            )
+           )
 {-# INLINE safeYYHandler #-}
 
 isEINTR :: IOError -> Bool
@@ -430,8 +436,8 @@
     Ptr (Ptr NgxStrType) -> Ptr CInt ->
     Ptr (StablePtr L.ByteString) -> IO CUInt
 yY f x (I n) p pl spd = do
-    (s, r) <- safeYYHandler $
-        flip (,) 0 . f <$> B.unsafePackCStringLen (x, n)
+    (s, (r, _)) <- safeYYHandler $
+        flip (,) (0, False) . f <$> B.unsafePackCStringLen (x, n)
     pokeLazyByteString s p pl spd
     return r
 
@@ -439,9 +445,9 @@
     Ptr (Ptr NgxStrType) -> Ptr CInt ->
     Ptr (StablePtr L.ByteString) -> IO CUInt
 ioyY f x (I n) p pl spd = do
-    (s, r) <- safeYYHandler $ do
+    (s, (r, _)) <- safeYYHandler $ do
         s <- B.unsafePackCStringLen (x, n) >>= flip f False
-        fmap (flip (,) 0) $ return $! s
+        fmap (flip (,) (0, False)) $ return $! s
     pokeLazyByteString s p pl spd
     return r
 
@@ -457,17 +463,20 @@
 asyncIOCommon a (I fd) efd p pl pr spd =
     async
     (do
-        (s, r) <- safeYYHandler $ do
+        (s, (r, exiting)) <- safeYYHandler $ do
             s <- a
-            fmap (flip (,) 0) $ return $! s
+            fmap (flip (,) (0, False)) $ return $! s
         pokeLazyByteString s p pl spd
         poke pr r
-        uninterruptibleMask_ $
-            if efd
-                then writeFlag8b
-                else writeFlag1b >> closeFd fd `catchIOError` const (return ())
+        if exiting
+            then unless efd closeChannel
+            else uninterruptibleMask_ $
+                    if efd
+                        then writeFlag8b
+                        else writeFlag1b >> closeChannel
     ) >>= newStablePtr
-    where writeBufN n s = iterateUntilM (>= n)
+    where writeBufN n s = void $
+              iterateUntilM (>= n)
               (\w -> (w +) <$>
                   fdWriteBuf fd (plusPtr s $ fromIntegral w) (n - w)
                   `catchIOError`
@@ -476,8 +485,9 @@
                                       else n
                   )
               ) 0
-          writeFlag1b = void $ B.unsafeUseAsCString asyncIOFlag1b $ writeBufN 1
-          writeFlag8b = void $ B.unsafeUseAsCString asyncIOFlag8b $ writeBufN 8
+          writeFlag1b = B.unsafeUseAsCString asyncIOFlag1b $ writeBufN 1
+          writeFlag8b = B.unsafeUseAsCString asyncIOFlag8b $ writeBufN 8
+          closeChannel = closeFd fd `catchIOError` const (return ())
 
 asyncIOYY :: IOYY -> CString -> CInt ->
     CInt -> CInt -> CUInt -> CUInt -> Ptr (Ptr NgxStrType) -> Ptr CInt ->
@@ -493,12 +503,8 @@
                                     return (True, False)
                            )
                            `catches`
-                           [E.Handler
-                                ((\e -> return (not (isEINTR e), False)) ::
-                                    IOError -> IO (Bool, Bool))
-                           ,E.Handler
-                                ((\e -> return (True, e == ThreadKilled)) ::
-                                    AsyncException -> IO (Bool, Bool))
+                           [E.Handler $ return . flip (,) False . not . isEINTR
+                           ,E.Handler $ return . (,) True . (== ThreadKilled)
                            ]
                        else return False
         if exiting
diff --git a/ngx-export.cabal b/ngx-export.cabal
--- a/ngx-export.cabal
+++ b/ngx-export.cabal
@@ -1,5 +1,5 @@
 name:                       ngx-export
-version:                    0.9.0.0
+version:                    0.9.1.0
 synopsis:                   Helper module for Nginx haskell module
 description:                Helper module for
         <http://github.com/lyokha/nginx-haskell-module Nginx haskell module>