diff --git a/src/core/ngx_buf.h b/src/core/ngx_buf.h
index 13536a69a..219894ffc 100644
--- a/src/core/ngx_buf.h
+++ b/src/core/ngx_buf.h
@@ -94,6 +94,9 @@ struct ngx_output_chain_ctx_s {
     unsigned                     aio:1;
 
     ngx_output_chain_aio_pt      aio_handler;
+#if (NGX_HAVE_FILE_AIO)
+    ssize_t                    (*aio_preload)(ngx_buf_t *file);
+#endif
 #endif
 
     off_t                        alignment;
diff --git a/src/core/ngx_connection.h b/src/core/ngx_connection.h
index ed14e6023..143cab7b3 100644
--- a/src/core/ngx_connection.h
+++ b/src/core/ngx_connection.h
@@ -181,9 +181,7 @@ struct ngx_connection_s {
 #endif
 
 #if (NGX_HAVE_AIO_SENDFILE)
-    unsigned            aio_sendfile:1;
     unsigned            busy_count:2;
-    ngx_buf_t          *busy_sendfile;
 #endif
 
 #if (NGX_THREADS)
diff --git a/src/core/ngx_output_chain.c b/src/core/ngx_output_chain.c
index 9d7a8460f..ca390e254 100644
--- a/src/core/ngx_output_chain.c
+++ b/src/core/ngx_output_chain.c
@@ -29,6 +29,10 @@
 
 static ngx_inline ngx_int_t
     ngx_output_chain_as_is(ngx_output_chain_ctx_t *ctx, ngx_buf_t *buf);
+#if (NGX_HAVE_AIO_SENDFILE)
+static ngx_int_t ngx_output_chain_aio_setup(ngx_output_chain_ctx_t *ctx,
+    ngx_file_t *file);
+#endif
 static ngx_int_t ngx_output_chain_add_copy(ngx_pool_t *pool,
     ngx_chain_t **chain, ngx_chain_t *in);
 static ngx_int_t ngx_output_chain_align_file_buf(ngx_output_chain_ctx_t *ctx,
@@ -252,6 +256,12 @@ ngx_output_chain_as_is(ngx_output_chain_ctx_t *ctx, ngx_buf_t *buf)
         buf->in_file = 0;
     }
 
+#if (NGX_HAVE_AIO_SENDFILE)
+    if (ctx->aio_preload && buf->in_file) {
+        (void) ngx_output_chain_aio_setup(ctx, buf->file);
+    }
+#endif
+
     if (ctx->need_in_memory && !ngx_buf_in_memory(buf)) {
         return 0;
     }
@@ -264,6 +274,28 @@ ngx_output_chain_as_is(ngx_output_chain_ctx_t *ctx, ngx_buf_t *buf)
 }
 
 
+#if (NGX_HAVE_AIO_SENDFILE)
+
+static ngx_int_t
+ngx_output_chain_aio_setup(ngx_output_chain_ctx_t *ctx, ngx_file_t *file)
+{
+    ngx_event_aio_t  *aio;
+
+    if (file->aio == NULL && ngx_file_aio_init(file, ctx->pool) != NGX_OK) {
+        return NGX_ERROR;
+    }
+
+    aio = file->aio;
+
+    aio->data = ctx->filter_ctx;
+    aio->preload_handler = ctx->aio_preload;
+
+    return NGX_OK;
+}
+
+#endif
+
+
 static ngx_int_t
 ngx_output_chain_add_copy(ngx_pool_t *pool, ngx_chain_t **chain,
     ngx_chain_t *in)
diff --git a/src/event/ngx_event.h b/src/event/ngx_event.h
index a1643a134..555cda0f4 100644
--- a/src/event/ngx_event.h
+++ b/src/event/ngx_event.h
@@ -168,6 +168,10 @@ struct ngx_event_aio_s {
     ngx_event_handler_pt       handler;
     ngx_file_t                *file;
 
+#if (NGX_HAVE_AIO_SENDFILE)
+    ssize_t                  (*preload_handler)(ngx_buf_t *file);
+#endif
+
     ngx_fd_t                   fd;
 
 #if (NGX_HAVE_EVENTFD)
@@ -181,10 +185,6 @@ struct ngx_event_aio_s {
     size_t                     nbytes;
 #endif
 
-#if (NGX_HAVE_AIO_SENDFILE)
-    off_t                      last_offset;
-#endif
-
     ngx_aiocb_t                aiocb;
     ngx_event_t                event;
 };
diff --git a/src/http/ngx_http_copy_filter_module.c b/src/http/ngx_http_copy_filter_module.c
index 3ad27b042..cdd7fceb6 100644
--- a/src/http/ngx_http_copy_filter_module.c
+++ b/src/http/ngx_http_copy_filter_module.c
@@ -20,6 +20,7 @@ static void ngx_http_copy_aio_handler(ngx_output_chain_ctx_t *ctx,
     ngx_file_t *file);
 static void ngx_http_copy_aio_event_handler(ngx_event_t *ev);
 #if (NGX_HAVE_AIO_SENDFILE)
+static ssize_t ngx_http_copy_aio_sendfile_preload(ngx_buf_t *file);
 static void ngx_http_copy_aio_sendfile_event_handler(ngx_event_t *ev);
 #endif
 #endif
@@ -125,7 +126,9 @@ ngx_http_copy_filter(ngx_http_request_t *r, ngx_chain_t *in)
                 ctx->aio_handler = ngx_http_copy_aio_handler;
             }
 #if (NGX_HAVE_AIO_SENDFILE)
-            c->aio_sendfile = (clcf->aio == NGX_HTTP_AIO_SENDFILE);
+            if (clcf->aio == NGX_HTTP_AIO_SENDFILE) {
+                ctx->aio_preload = ngx_http_copy_aio_sendfile_preload;
+            }
 #endif
         }
 #endif
@@ -139,72 +142,19 @@ ngx_http_copy_filter(ngx_http_request_t *r, ngx_chain_t *in)
     ctx->aio = r->aio;
 #endif
 
-    for ( ;; ) {
-        rc = ngx_output_chain(ctx, in);
+    rc = ngx_output_chain(ctx, in);
 
-        if (ctx->in == NULL) {
-            r->buffered &= ~NGX_HTTP_COPY_BUFFERED;
+    if (ctx->in == NULL) {
+        r->buffered &= ~NGX_HTTP_COPY_BUFFERED;
 
-        } else {
-            r->buffered |= NGX_HTTP_COPY_BUFFERED;
-        }
-
-        ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0,
-                       "http copy filter: %i \"%V?%V\"", rc, &r->uri, &r->args);
-
-#if (NGX_HAVE_FILE_AIO && NGX_HAVE_AIO_SENDFILE)
-
-        if (c->busy_sendfile) {
-            ssize_t                n;
-            off_t                  offset;
-            ngx_file_t            *file;
-            ngx_http_ephemeral_t  *e;
-
-            if (r->aio) {
-                c->busy_sendfile = NULL;
-                return rc;
-            }
-
-            file = c->busy_sendfile->file;
-            offset = c->busy_sendfile->file_pos;
-
-            if (file->aio) {
-                c->busy_count = (offset == file->aio->last_offset) ?
-                                c->busy_count + 1 : 0;
-                file->aio->last_offset = offset;
-
-                if (c->busy_count > 2) {
-                    ngx_log_error(NGX_LOG_ALERT, c->log, 0,
-                                  "sendfile(%V) returned busy again",
-                                  &file->name);
-                    c->aio_sendfile = 0;
-                }
-            }
-
-            c->busy_sendfile = NULL;
-            e = (ngx_http_ephemeral_t *) &r->uri_start;
-
-            n = ngx_file_aio_read(file, &e->aio_preload, 1, offset, r->pool);
-
-            if (n > 0) {
-                in = NULL;
-                continue;
-            }
-
-            rc = n;
-
-            if (rc == NGX_AGAIN) {
-                file->aio->data = r;
-                file->aio->handler = ngx_http_copy_aio_sendfile_event_handler;
-
-                r->main->blocked++;
-                r->aio = 1;
-            }
-        }
-#endif
-
-        return rc;
+    } else {
+        r->buffered |= NGX_HTTP_COPY_BUFFERED;
     }
+
+    ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                   "http copy filter: %i \"%V?%V\"", rc, &r->uri, &r->args);
+
+    return rc;
 }
 
 
@@ -244,6 +194,29 @@ ngx_http_copy_aio_event_handler(ngx_event_t *ev)
 
 #if (NGX_HAVE_AIO_SENDFILE)
 
+static ssize_t
+ngx_http_copy_aio_sendfile_preload(ngx_buf_t *file)
+{
+    ssize_t              n;
+    static u_char        buf[1];
+    ngx_event_aio_t     *aio;
+    ngx_http_request_t  *r;
+
+    n = ngx_file_aio_read(file->file, buf, 1, file->file_pos, NULL);
+
+    if (n == NGX_AGAIN) {
+        aio = file->file->aio;
+        aio->handler = ngx_http_copy_aio_sendfile_event_handler;
+
+        r = aio->data;
+        r->main->blocked++;
+        r->aio = 1;
+    }
+
+    return n;
+}
+
+
 static void
 ngx_http_copy_aio_sendfile_event_handler(ngx_event_t *ev)
 {
diff --git a/src/http/ngx_http_request.h b/src/http/ngx_http_request.h
index cffab9a69..9be0c6e71 100644
--- a/src/http/ngx_http_request.h
+++ b/src/http/ngx_http_request.h
@@ -574,9 +574,6 @@ struct ngx_http_request_s {
 
 typedef struct {
     ngx_http_posted_request_t         terminal_posted_request;
-#if (NGX_HAVE_AIO_SENDFILE)
-    u_char                            aio_preload;
-#endif
 } ngx_http_ephemeral_t;
 
 
diff --git a/src/os/unix/ngx_file_aio_read.c b/src/os/unix/ngx_file_aio_read.c
index 0bb383de5..b11cf8a3d 100644
--- a/src/os/unix/ngx_file_aio_read.c
+++ b/src/os/unix/ngx_file_aio_read.c
@@ -36,6 +36,28 @@ static ssize_t ngx_file_aio_result(ngx_file_t *file, ngx_event_aio_t *aio,
 static void ngx_file_aio_event_handler(ngx_event_t *ev);
 
 
+ngx_int_t
+ngx_file_aio_init(ngx_file_t *file, ngx_pool_t *pool)
+{
+    ngx_event_aio_t  *aio;
+
+    aio = ngx_pcalloc(pool, sizeof(ngx_event_aio_t));
+    if (aio == NULL) {
+        return NGX_ERROR;
+    }
+
+    aio->file = file;
+    aio->fd = file->fd;
+    aio->event.data = aio;
+    aio->event.ready = 1;
+    aio->event.log = file->log;
+
+    file->aio = aio;
+
+    return NGX_OK;
+}
+
+
 ssize_t
 ngx_file_aio_read(ngx_file_t *file, u_char *buf, size_t size, off_t offset,
     ngx_pool_t *pool)
@@ -48,25 +70,11 @@ ngx_file_aio_read(ngx_file_t *file, u_char *buf, size_t size, off_t offset,
         return ngx_read_file(file, buf, size, offset);
     }
 
-    aio = file->aio;
-
-    if (aio == NULL) {
-        aio = ngx_pcalloc(pool, sizeof(ngx_event_aio_t));
-        if (aio == NULL) {
-            return NGX_ERROR;
-        }
-
-        aio->file = file;
-        aio->fd = file->fd;
-        aio->event.data = aio;
-        aio->event.ready = 1;
-        aio->event.log = file->log;
-#if (NGX_HAVE_AIO_SENDFILE)
-        aio->last_offset = -1;
-#endif
-        file->aio = aio;
+    if (file->aio == NULL && ngx_file_aio_init(file, pool) != NGX_OK) {
+        return NGX_ERROR;
     }
 
+    aio = file->aio;
     ev = &aio->event;
 
     if (!ev->ready) {
diff --git a/src/os/unix/ngx_files.h b/src/os/unix/ngx_files.h
index a78ec9613..a046ee756 100644
--- a/src/os/unix/ngx_files.h
+++ b/src/os/unix/ngx_files.h
@@ -375,6 +375,7 @@ size_t ngx_fs_bsize(u_char *name);
 
 #if (NGX_HAVE_FILE_AIO)
 
+ngx_int_t ngx_file_aio_init(ngx_file_t *file, ngx_pool_t *pool);
 ssize_t ngx_file_aio_read(ngx_file_t *file, u_char *buf, size_t size,
     off_t offset, ngx_pool_t *pool);
 
diff --git a/src/os/unix/ngx_freebsd_sendfile_chain.c b/src/os/unix/ngx_freebsd_sendfile_chain.c
index 7199c8654..25790b6b6 100644
--- a/src/os/unix/ngx_freebsd_sendfile_chain.c
+++ b/src/os/unix/ngx_freebsd_sendfile_chain.c
@@ -32,19 +32,23 @@
 ngx_chain_t *
 ngx_freebsd_sendfile_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit)
 {
-    int              rc, flags;
-    off_t            send, prev_send, sent;
-    size_t           file_size;
-    ssize_t          n;
-    ngx_uint_t       eintr, eagain;
-    ngx_err_t        err;
-    ngx_buf_t       *file;
-    ngx_event_t     *wev;
-    ngx_chain_t     *cl;
-    ngx_iovec_t      header, trailer;
-    struct sf_hdtr   hdtr;
-    struct iovec     headers[NGX_IOVS_PREALLOCATE];
-    struct iovec     trailers[NGX_IOVS_PREALLOCATE];
+    int               rc, flags;
+    off_t             send, prev_send, sent;
+    size_t            file_size;
+    ssize_t           n;
+    ngx_uint_t        eintr, eagain;
+    ngx_err_t         err;
+    ngx_buf_t        *file;
+    ngx_event_t      *wev;
+    ngx_chain_t      *cl;
+    ngx_iovec_t       header, trailer;
+    struct sf_hdtr    hdtr;
+    struct iovec      headers[NGX_IOVS_PREALLOCATE];
+    struct iovec      trailers[NGX_IOVS_PREALLOCATE];
+#if (NGX_HAVE_AIO_SENDFILE)
+    ngx_uint_t        ebusy;
+    ngx_event_aio_t  *aio;
+#endif
 
     wev = c->write;
 
@@ -73,6 +77,11 @@ ngx_freebsd_sendfile_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit)
     eagain = 0;
     flags = 0;
 
+#if (NGX_HAVE_AIO_SENDFILE && NGX_SUPPRESS_WARN)
+    aio = NULL;
+    file = NULL;
+#endif
+
     header.iovs = headers;
     header.nalloc = NGX_IOVS_PREALLOCATE;
 
@@ -81,6 +90,9 @@ ngx_freebsd_sendfile_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit)
 
     for ( ;; ) {
         eintr = 0;
+#if (NGX_HAVE_AIO_SENDFILE)
+        ebusy = 0;
+#endif
         prev_send = send;
 
         /* create the header iovec and coalesce the neighbouring bufs */
@@ -160,7 +172,8 @@ ngx_freebsd_sendfile_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit)
             sent = 0;
 
 #if (NGX_HAVE_AIO_SENDFILE)
-            flags = c->aio_sendfile ? SF_NODISKIO : 0;
+            aio = file->file->aio;
+            flags = (aio && aio->preload_handler) ? SF_NODISKIO : 0;
 #endif
 
             rc = sendfile(file->file->fd, c->fd, file->file_pos,
@@ -180,7 +193,7 @@ ngx_freebsd_sendfile_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit)
 
 #if (NGX_HAVE_AIO_SENDFILE)
                 case NGX_EBUSY:
-                    c->busy_sendfile = file;
+                    ebusy = 1;
                     break;
 #endif
 
@@ -232,9 +245,41 @@ ngx_freebsd_sendfile_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit)
         in = ngx_chain_update_sent(in, sent);
 
 #if (NGX_HAVE_AIO_SENDFILE)
-        if (c->busy_sendfile) {
+
+        if (ebusy) {
+            if (sent == 0) {
+                c->busy_count++;
+
+                if (c->busy_count > 2) {
+                    ngx_log_error(NGX_LOG_ALERT, c->log, 0,
+                                  "sendfile(%V) returned busy again",
+                                  &file->file->name);
+
+                    c->busy_count = 0;
+                    aio->preload_handler = NULL;
+
+                    send = prev_send;
+                    continue;
+                }
+
+            } else {
+                c->busy_count = 0;
+            }
+
+            rc = aio->preload_handler(file);
+
+            if (rc > 0) {
+                send = prev_send + sent;
+                continue;
+            }
+
             return in;
         }
+
+        if (flags == SF_NODISKIO) {
+            c->busy_count = 0;
+        }
+
 #endif
 
         if (eagain) {
diff --git a/src/os/unix/ngx_linux_aio_read.c b/src/os/unix/ngx_linux_aio_read.c
index 8273c13f9..b0a923604 100644
--- a/src/os/unix/ngx_linux_aio_read.c
+++ b/src/os/unix/ngx_linux_aio_read.c
@@ -24,6 +24,28 @@ io_submit(aio_context_t ctx, long n, struct iocb **paiocb)
 }
 
 
+ngx_int_t
+ngx_file_aio_init(ngx_file_t *file, ngx_pool_t *pool)
+{
+    ngx_event_aio_t  *aio;
+
+    aio = ngx_pcalloc(pool, sizeof(ngx_event_aio_t));
+    if (aio == NULL) {
+        return NGX_ERROR;
+    }
+
+    aio->file = file;
+    aio->fd = file->fd;
+    aio->event.data = aio;
+    aio->event.ready = 1;
+    aio->event.log = file->log;
+
+    file->aio = aio;
+
+    return NGX_OK;
+}
+
+
 ssize_t
 ngx_file_aio_read(ngx_file_t *file, u_char *buf, size_t size, off_t offset,
     ngx_pool_t *pool)
@@ -37,22 +59,11 @@ ngx_file_aio_read(ngx_file_t *file, u_char *buf, size_t size, off_t offset,
         return ngx_read_file(file, buf, size, offset);
     }
 
-    aio = file->aio;
-
-    if (aio == NULL) {
-        aio = ngx_pcalloc(pool, sizeof(ngx_event_aio_t));
-        if (aio == NULL) {
-            return NGX_ERROR;
-        }
-
-        aio->file = file;
-        aio->fd = file->fd;
-        aio->event.data = aio;
-        aio->event.ready = 1;
-        aio->event.log = file->log;
-        file->aio = aio;
+    if (file->aio == NULL && ngx_file_aio_init(file, pool) != NGX_OK) {
+        return NGX_ERROR;
     }
 
+    aio = file->aio;
     ev = &aio->event;
 
     if (!ev->ready) {