Changes with nginx 1.1.4 20 Sep 2011v1.1.4

*) Feature: the ngx_http_upstream_keepalive module.

*) Feature: the "proxy_http_version" directive.

*) Feature: the "fastcgi_keep_conn" directive.

*) Feature: the "worker_aio_requests" directive.

*) Bugfix: if nginx was built --with-file-aio it could not be run on
Linux kernel which did not support AIO.

*) Bugfix: in Linux AIO error processing.
Thanks to Hagai Avrahami.

*) Bugfix: reduced memory consumption for long-lived requests.

*) Bugfix: the module ngx_http_mp4_module did not support 64-bit MP4
"co64" atom.

11 files changed, 1683 insertions, 68 deletions

diff --git a/src/http/modules/ngx_http_chunked_filter_module.c b/src/http/modules/ngx_http_chunked_filter_module.c
index 9c4c5de14..e6ae1c99d 100644
--- a/src/http/modules/ngx_http_chunked_filter_module.c
+++ b/src/http/modules/ngx_http_chunked_filter_module.c
@@ -9,6 +9,12 @@
 #include <ngx_http.h>
 
 
+typedef struct {
+    ngx_chain_t         *free;
+    ngx_chain_t         *busy;
+} ngx_http_chunked_filter_ctx_t;
+
+
 static ngx_int_t ngx_http_chunked_filter_init(ngx_conf_t *cf);
 
 
@@ -50,7 +56,8 @@ static ngx_http_output_body_filter_pt    ngx_http_next_body_filter;
 static ngx_int_t
 ngx_http_chunked_header_filter(ngx_http_request_t *r)
 {
-    ngx_http_core_loc_conf_t  *clcf;
+    ngx_http_core_loc_conf_t       *clcf;
+    ngx_http_chunked_filter_ctx_t  *ctx;
 
     if (r->headers_out.status == NGX_HTTP_NOT_MODIFIED
         || r->headers_out.status == NGX_HTTP_NO_CONTENT
@@ -70,6 +77,14 @@ ngx_http_chunked_header_filter(ngx_http_request_t *r)
             if (clcf->chunked_transfer_encoding) {
                 r->chunked = 1;
 
+                ctx = ngx_pcalloc(r->pool,
+                                  sizeof(ngx_http_chunked_filter_ctx_t));
+                if (ctx == NULL) {
+                    return NGX_ERROR;
+                }
+
+                ngx_http_set_ctx(r, ctx, ngx_http_chunked_filter_module);
+
             } else {
                 r->keepalive = 0;
             }
@@ -83,17 +98,21 @@ ngx_http_chunked_header_filter(ngx_http_request_t *r)
 static ngx_int_t
 ngx_http_chunked_body_filter(ngx_http_request_t *r, ngx_chain_t *in)
 {
-    u_char       *chunk;
-    off_t         size;
-    ngx_buf_t    *b;
-    ngx_chain_t   out, tail, *cl, *tl, **ll;
+    u_char                         *chunk;
+    off_t                           size;
+    ngx_int_t                       rc;
+    ngx_buf_t                      *b;
+    ngx_chain_t                    *out, *cl, *tl, **ll;
+    ngx_http_chunked_filter_ctx_t  *ctx;
 
     if (in == NULL || !r->chunked || r->header_only) {
         return ngx_http_next_body_filter(r, in);
     }
 
-    out.buf = NULL;
-    ll = &out.next;
+    ctx = ngx_http_get_module_ctx(r, ngx_http_chunked_filter_module);
+
+    out = NULL;
+    ll = &out;
 
     size = 0;
     cl = in;
@@ -127,31 +146,46 @@ ngx_http_chunked_body_filter(ngx_http_request_t *r, ngx_chain_t *in)
     }
 
     if (size) {
-        b = ngx_calloc_buf(r->pool);
-        if (b == NULL) {
+        tl = ngx_chain_get_free_buf(r->pool, &ctx->free);
+        if (tl == NULL) {
             return NGX_ERROR;
         }
 
-        /* the "0000000000000000" is 64-bit hexadimal string */
+        b = tl->buf;
+        chunk = b->start;
 
-        chunk = ngx_palloc(r->pool, sizeof("0000000000000000" CRLF) - 1);
         if (chunk == NULL) {
-            return NGX_ERROR;
+            /* the "0000000000000000" is 64-bit hexadecimal string */
+
+            chunk = ngx_palloc(r->pool, sizeof("0000000000000000" CRLF) - 1);
+            if (chunk == NULL) {
+                return NGX_ERROR;
+            }
+
+            b->start = chunk;
+            b->end = chunk + sizeof("0000000000000000" CRLF) - 1;
         }
 
+        b->tag = (ngx_buf_tag_t) &ngx_http_chunked_filter_module;
+        b->memory = 0;
         b->temporary = 1;
         b->pos = chunk;
         b->last = ngx_sprintf(chunk, "%xO" CRLF, size);
 
-        out.buf = b;
+        tl->next = out;
+        out = tl;
     }
 
     if (cl->buf->last_buf) {
-        b = ngx_calloc_buf(r->pool);
-        if (b == NULL) {
+        tl = ngx_chain_get_free_buf(r->pool, &ctx->free);
+        if (tl == NULL) {
             return NGX_ERROR;
         }
 
+        b = tl->buf;
+
+        b->tag = (ngx_buf_tag_t) &ngx_http_chunked_filter_module;
+        b->temporary = 0;
         b->memory = 1;
         b->last_buf = 1;
         b->pos = (u_char *) CRLF "0" CRLF CRLF;
@@ -159,35 +193,38 @@ ngx_http_chunked_body_filter(ngx_http_request_t *r, ngx_chain_t *in)
 
         cl->buf->last_buf = 0;
 
-        if (size == 0) {
-            b->pos += 2;
-            out.buf = b;
-            out.next = NULL;
-
-            return ngx_http_next_body_filter(r, &out);
-        }
+        *ll = tl;
 
-    } else {
         if (size == 0) {
-            *ll = NULL;
-            return ngx_http_next_body_filter(r, out.next);
+            b->pos += 2;
         }
 
-        b = ngx_calloc_buf(r->pool);
-        if (b == NULL) {
+    } else if (size > 0) {
+        tl = ngx_chain_get_free_buf(r->pool, &ctx->free);
+        if (tl == NULL) {
             return NGX_ERROR;
         }
 
+        b = tl->buf;
+
+        b->tag = (ngx_buf_tag_t) &ngx_http_chunked_filter_module;
+        b->temporary = 0;
         b->memory = 1;
         b->pos = (u_char *) CRLF;
         b->last = b->pos + 2;
+
+        *ll = tl;
+
+    } else {
+        *ll = NULL;
     }
 
-    tail.buf = b;
-    tail.next = NULL;
-    *ll = &tail;
+    rc = ngx_http_next_body_filter(r, out);
+
+    ngx_chain_update_chains(r->pool, &ctx->free, &ctx->busy, &out,
+                            (ngx_buf_tag_t) &ngx_http_chunked_filter_module);
 
-    return ngx_http_next_body_filter(r, &out);
+    return rc;
 }
 
 
diff --git a/src/http/modules/ngx_http_dav_module.c b/src/http/modules/ngx_http_dav_module.c
index 0761c1654..3bd9d3e94 100644
--- a/src/http/modules/ngx_http_dav_module.c
+++ b/src/http/modules/ngx_http_dav_module.c
@@ -158,7 +158,7 @@ ngx_http_dav_handler(ngx_http_request_t *r)
 
         if (r->uri.data[r->uri.len - 1] == '/') {
             ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
-                          "can not PUT to a collection");
+                          "cannot PUT to a collection");
             return NGX_HTTP_CONFLICT;
         }
 
diff --git a/src/http/modules/ngx_http_fastcgi_module.c b/src/http/modules/ngx_http_fastcgi_module.c
index 0bc95f8da..6f639acc2 100644
--- a/src/http/modules/ngx_http_fastcgi_module.c
+++ b/src/http/modules/ngx_http_fastcgi_module.c
@@ -26,6 +26,8 @@ typedef struct {
     ngx_hash_t                     headers_hash;
     ngx_uint_t                     header_params;
 
+    ngx_flag_t                     keep_conn;
+
 #if (NGX_HTTP_CACHE)
     ngx_http_complex_value_t       cache_key;
 #endif
@@ -77,6 +79,8 @@ typedef struct {
 
 #define NGX_HTTP_FASTCGI_RESPONDER      1
 
+#define NGX_HTTP_FASTCGI_KEEP_CONN      1
+
 #define NGX_HTTP_FASTCGI_BEGIN_REQUEST  1
 #define NGX_HTTP_FASTCGI_ABORT_REQUEST  2
 #define NGX_HTTP_FASTCGI_END_REQUEST    3
@@ -130,6 +134,7 @@ static ngx_int_t ngx_http_fastcgi_create_key(ngx_http_request_t *r);
 static ngx_int_t ngx_http_fastcgi_create_request(ngx_http_request_t *r);
 static ngx_int_t ngx_http_fastcgi_reinit_request(ngx_http_request_t *r);
 static ngx_int_t ngx_http_fastcgi_process_header(ngx_http_request_t *r);
+static ngx_int_t ngx_http_fastcgi_input_filter_init(void *data);
 static ngx_int_t ngx_http_fastcgi_input_filter(ngx_event_pipe_t *p,
     ngx_buf_t *buf);
 static ngx_int_t ngx_http_fastcgi_process_record(ngx_http_request_t *r,
@@ -437,6 +442,13 @@ static ngx_command_t  ngx_http_fastcgi_commands[] = {
       offsetof(ngx_http_fastcgi_loc_conf_t, catch_stderr),
       NULL },
 
+    { ngx_string("fastcgi_keep_conn"),
+      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
+      ngx_conf_set_flag_slot,
+      NGX_HTTP_LOC_CONF_OFFSET,
+      offsetof(ngx_http_fastcgi_loc_conf_t, keep_conn),
+      NULL },
+
       ngx_null_command
 };
 
@@ -600,6 +612,8 @@ ngx_http_fastcgi_handler(ngx_http_request_t *r)
     u->pipe->input_filter = ngx_http_fastcgi_input_filter;
     u->pipe->input_ctx = r;
 
+    u->input_filter_init = ngx_http_fastcgi_input_filter_init;
+
     rc = ngx_http_read_client_request_body(r, ngx_http_upstream_init);
 
     if (rc >= NGX_HTTP_SPECIAL_RESPONSE) {
@@ -841,6 +855,9 @@ ngx_http_fastcgi_create_request(ngx_http_request_t *r)
 
     cl->buf = b;
 
+    ngx_http_fastcgi_request_start.br.flags =
+        flcf->keep_conn ? NGX_HTTP_FASTCGI_KEEP_CONN : 0;
+
     ngx_memcpy(b->pos, &ngx_http_fastcgi_request_start,
                sizeof(ngx_http_fastcgi_request_start_t));
 
@@ -1574,14 +1591,30 @@ ngx_http_fastcgi_process_header(ngx_http_request_t *r)
 
 
 static ngx_int_t
+ngx_http_fastcgi_input_filter_init(void *data)
+{
+    ngx_http_request_t           *r = data;
+    ngx_http_fastcgi_loc_conf_t  *flcf;
+
+    flcf = ngx_http_get_module_loc_conf(r, ngx_http_fastcgi_module);
+
+    r->upstream->pipe->length = flcf->keep_conn ?
+                                (off_t) sizeof(ngx_http_fastcgi_header_t) : -1;
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
 ngx_http_fastcgi_input_filter(ngx_event_pipe_t *p, ngx_buf_t *buf)
 {
-    u_char                  *m, *msg;
-    ngx_int_t                rc;
-    ngx_buf_t               *b, **prev;
-    ngx_chain_t             *cl;
-    ngx_http_request_t      *r;
-    ngx_http_fastcgi_ctx_t  *f;
+    u_char                       *m, *msg;
+    ngx_int_t                     rc;
+    ngx_buf_t                    *b, **prev;
+    ngx_chain_t                  *cl;
+    ngx_http_request_t           *r;
+    ngx_http_fastcgi_ctx_t       *f;
+    ngx_http_fastcgi_loc_conf_t  *flcf;
 
     if (buf->pos == buf->last) {
         return NGX_OK;
@@ -1589,6 +1622,7 @@ ngx_http_fastcgi_input_filter(ngx_event_pipe_t *p, ngx_buf_t *buf)
 
     r = p->input_ctx;
     f = ngx_http_get_module_ctx(r, ngx_http_fastcgi_module);
+    flcf = ngx_http_get_module_loc_conf(r, ngx_http_fastcgi_module);
 
     b = NULL;
     prev = &buf->shadow;
@@ -1611,7 +1645,10 @@ ngx_http_fastcgi_input_filter(ngx_event_pipe_t *p, ngx_buf_t *buf)
 
             if (f->type == NGX_HTTP_FASTCGI_STDOUT && f->length == 0) {
                 f->state = ngx_http_fastcgi_st_version;
-                p->upstream_done = 1;
+
+                if (!flcf->keep_conn) {
+                    p->upstream_done = 1;
+                }
 
                 ngx_log_debug0(NGX_LOG_DEBUG_HTTP, p->log, 0,
                                "http fastcgi closed stdout");
@@ -1623,6 +1660,10 @@ ngx_http_fastcgi_input_filter(ngx_event_pipe_t *p, ngx_buf_t *buf)
                 f->state = ngx_http_fastcgi_st_version;
                 p->upstream_done = 1;
 
+                if (flcf->keep_conn) {
+                    r->upstream->keepalive = 1;
+                }
+
                 ngx_log_debug0(NGX_LOG_DEBUG_HTTP, p->log, 0,
                                "http fastcgi sent end request");
 
@@ -1703,8 +1744,10 @@ ngx_http_fastcgi_input_filter(ngx_event_pipe_t *p, ngx_buf_t *buf)
         }
 
         if (p->free) {
-            b = p->free->buf;
-            p->free = p->free->next;
+            cl = p->free;
+            b = cl->buf;
+            p->free = cl->next;
+            ngx_free_chain(p->pool, cl);
 
         } else {
             b = ngx_alloc_buf(p->pool);
@@ -1781,6 +1824,23 @@ ngx_http_fastcgi_input_filter(ngx_event_pipe_t *p, ngx_buf_t *buf)
 
     }
 
+    if (flcf->keep_conn) {
+
+        /* set p->length, minimal amount of data we want to see */
+
+        if (f->state < ngx_http_fastcgi_st_data) {
+            p->length = 1;
+
+        } else if (f->state == ngx_http_fastcgi_st_padding) {
+            p->length = f->padding;
+
+        } else {
+            /* ngx_http_fastcgi_st_data */
+
+            p->length = f->length;
+        }
+    }
+
     if (b) {
         b->shadow = buf;
         b->last_shadow = 1;
@@ -2011,6 +2071,8 @@ ngx_http_fastcgi_create_loc_conf(ngx_conf_t *cf)
 
     conf->catch_stderr = NGX_CONF_UNSET_PTR;
 
+    conf->keep_conn = NGX_CONF_UNSET;
+
     ngx_str_set(&conf->upstream.module, "fastcgi");
 
     return conf;
@@ -2254,6 +2316,8 @@ ngx_http_fastcgi_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
 
     ngx_conf_merge_ptr_value(conf->catch_stderr, prev->catch_stderr, NULL);
 
+    ngx_conf_merge_value(conf->keep_conn, prev->keep_conn, 0);
+
 
     ngx_conf_merge_str_value(conf->index, prev->index, "");
 
diff --git a/src/http/modules/ngx_http_gzip_filter_module.c b/src/http/modules/ngx_http_gzip_filter_module.c
index d624e36ff..18824059a 100644
--- a/src/http/modules/ngx_http_gzip_filter_module.c
+++ b/src/http/modules/ngx_http_gzip_filter_module.c
@@ -378,7 +378,7 @@ ngx_http_gzip_body_filter(ngx_http_request_t *r, ngx_chain_t *in)
 
         cl = NULL;
 
-        ngx_chain_update_chains(&ctx->free, &ctx->busy, &cl,
+        ngx_chain_update_chains(r->pool, &ctx->free, &ctx->busy, &cl,
                                 (ngx_buf_tag_t) &ngx_http_gzip_filter_module);
         ctx->nomem = 0;
     }
@@ -448,7 +448,7 @@ ngx_http_gzip_body_filter(ngx_http_request_t *r, ngx_chain_t *in)
 
         ngx_http_gzip_filter_free_copy_buf(r, ctx);
 
-        ngx_chain_update_chains(&ctx->free, &ctx->busy, &ctx->out,
+        ngx_chain_update_chains(r->pool, &ctx->free, &ctx->busy, &ctx->out,
                                 (ngx_buf_tag_t) &ngx_http_gzip_filter_module);
         ctx->last_out = &ctx->out;
 
diff --git a/src/http/modules/ngx_http_headers_filter_module.c b/src/http/modules/ngx_http_headers_filter_module.c
index 1d409582c..c3f74ae19 100644
--- a/src/http/modules/ngx_http_headers_filter_module.c
+++ b/src/http/modules/ngx_http_headers_filter_module.c
@@ -507,7 +507,7 @@ ngx_http_headers_expires(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
         minus = 0;
 
         if (hcf->expires == NGX_HTTP_EXPIRES_MODIFIED) {
-            return "daily time can not be used with \"modified\" parameter";
+            return "daily time cannot be used with \"modified\" parameter";
         }
 
         hcf->expires = NGX_HTTP_EXPIRES_DAILY;
diff --git a/src/http/modules/ngx_http_log_module.c b/src/http/modules/ngx_http_log_module.c
index b2bfbf477..9728d5411 100644
--- a/src/http/modules/ngx_http_log_module.c
+++ b/src/http/modules/ngx_http_log_module.c
@@ -960,7 +960,7 @@ buffer:
 
         if (log->script) {
             ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
-                               "buffered logs can not have variables in name");
+                               "buffered logs cannot have variables in name");
             return NGX_CONF_ERROR;
         }
 
diff --git a/src/http/modules/ngx_http_memcached_module.c b/src/http/modules/ngx_http_memcached_module.c
index 745f73aa5..dbe0fe838 100644
--- a/src/http/modules/ngx_http_memcached_module.c
+++ b/src/http/modules/ngx_http_memcached_module.c
@@ -344,8 +344,8 @@ found:
 
         while (*p && *p++ != CR) { /* void */ }
 
-        r->headers_out.content_length_n = ngx_atoof(len, p - len - 1);
-        if (r->headers_out.content_length_n == -1) {
+        u->headers_in.content_length_n = ngx_atoof(len, p - len - 1);
+        if (u->headers_in.content_length_n == -1) {
             ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                           "memcached sent invalid length in response \"%V\" "
                           "for key \"%V\"",
@@ -366,6 +366,7 @@ found:
 
         u->headers_in.status_n = 404;
         u->state->status = 404;
+        u->keepalive = 1;
 
         return NGX_OK;
     }
@@ -407,7 +408,7 @@ ngx_http_memcached_filter(void *data, ssize_t bytes)
     u = ctx->request->upstream;
     b = &u->buffer;
 
-    if (u->length == ctx->rest) {
+    if (u->length == (ssize_t) ctx->rest) {
 
         if (ngx_strncmp(b->last,
                    ngx_http_memcached_end + NGX_HTTP_MEMCACHED_END - ctx->rest,
@@ -426,6 +427,10 @@ ngx_http_memcached_filter(void *data, ssize_t bytes)
         u->length -= bytes;
         ctx->rest -= bytes;
 
+        if (u->length == 0) {
+            u->keepalive = 1;
+        }
+
         return NGX_OK;
     }
 
@@ -463,6 +468,13 @@ ngx_http_memcached_filter(void *data, ssize_t bytes)
     if (ngx_strncmp(last, ngx_http_memcached_end, b->last - last) != 0) {
         ngx_log_error(NGX_LOG_ERR, ctx->request->connection->log, 0,
                       "memcached sent invalid trailer");
+
+        b->last = last;
+        cl->buf->last = last;
+        u->length = 0;
+        ctx->rest = 0;
+
+        return NGX_OK;
     }
 
     ctx->rest -= b->last - last;
@@ -470,6 +482,10 @@ ngx_http_memcached_filter(void *data, ssize_t bytes)
     cl->buf->last = last;
     u->length = ctx->rest;
 
+    if (u->length == 0) {
+        u->keepalive = 1;
+    }
+
     return NGX_OK;
 }
 
diff --git a/src/http/modules/ngx_http_mp4_module.c b/src/http/modules/ngx_http_mp4_module.c
index fc21ec410..9a3362e8d 100644
--- a/src/http/modules/ngx_http_mp4_module.c
+++ b/src/http/modules/ngx_http_mp4_module.c
@@ -32,8 +32,10 @@
 #define NGX_HTTP_MP4_STSZ_DATA    21
 #define NGX_HTTP_MP4_STCO_ATOM    22
 #define NGX_HTTP_MP4_STCO_DATA    23
+#define NGX_HTTP_MP4_CO64_ATOM    24
+#define NGX_HTTP_MP4_CO64_DATA    25
 
-#define NGX_HTTP_MP4_LAST_ATOM    NGX_HTTP_MP4_STCO_DATA
+#define NGX_HTTP_MP4_LAST_ATOM    NGX_HTTP_MP4_CO64_DATA
 
 
 typedef struct {
@@ -61,7 +63,7 @@ typedef struct {
     ngx_uint_t            start_sample;
     ngx_uint_t            start_chunk;
     ngx_uint_t            chunk_samples;
-    ngx_uint_t            chunk_samples_size;
+    uint64_t              chunk_samples_size;
     off_t                 start_offset;
 
     size_t                tkhd_size;
@@ -96,8 +98,10 @@ typedef struct {
     ngx_buf_t             stsc_data_buf;
     ngx_buf_t             stsz_atom_buf;
     ngx_buf_t             stsz_data_buf;
-    ngx_buf_t             tsco_atom_buf;
-    ngx_buf_t             tsco_data_buf;
+    ngx_buf_t             stco_atom_buf;
+    ngx_buf_t             stco_data_buf;
+    ngx_buf_t             co64_atom_buf;
+    ngx_buf_t             co64_data_buf;
 
     ngx_mp4_stsc_entry_t  stsc_chunk_entry;
 } ngx_http_mp4_trak_t;
@@ -268,6 +272,12 @@ static ngx_int_t ngx_http_mp4_update_stco_atom(ngx_http_mp4_file_t *mp4,
     ngx_http_mp4_trak_t *trak);
 static void ngx_http_mp4_adjust_stco_atom(ngx_http_mp4_file_t *mp4,
     ngx_http_mp4_trak_t *trak, int32_t adjustment);
+static ngx_int_t ngx_http_mp4_read_co64_atom(ngx_http_mp4_file_t *mp4,
+    uint64_t atom_data_size);
+static ngx_int_t ngx_http_mp4_update_co64_atom(ngx_http_mp4_file_t *mp4,
+    ngx_http_mp4_trak_t *trak);
+static void ngx_http_mp4_adjust_co64_atom(ngx_http_mp4_file_t *mp4,
+    ngx_http_mp4_trak_t *trak, off_t adjustment);
 static char *ngx_http_mp4(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
 static void *ngx_http_mp4_create_conf(ngx_conf_t *cf);
 static char *ngx_http_mp4_merge_conf(ngx_conf_t *cf, void *parent, void *child);
@@ -373,6 +383,7 @@ static ngx_http_mp4_atom_handler_t  ngx_http_mp4_stbl_atoms[] = {
     { "stsc", ngx_http_mp4_read_stsc_atom },
     { "stsz", ngx_http_mp4_read_stsz_atom },
     { "stco", ngx_http_mp4_read_stco_atom },
+    { "co64", ngx_http_mp4_read_co64_atom },
     { NULL, NULL }
 };
 
@@ -676,8 +687,15 @@ ngx_http_mp4_process(ngx_http_mp4_file_t *mp4)
 
         ngx_http_mp4_update_stsz_atom(mp4, &trak[i]);
 
-        if (ngx_http_mp4_update_stco_atom(mp4, &trak[i]) != NGX_OK) {
-            return NGX_ERROR;
+        if (trak[i].out[NGX_HTTP_MP4_CO64_DATA].buf) {
+            if (ngx_http_mp4_update_co64_atom(mp4, &trak[i]) != NGX_OK) {
+                return NGX_ERROR;
+            }
+
+        } else {
+            if (ngx_http_mp4_update_stco_atom(mp4, &trak[i]) != NGX_OK) {
+                return NGX_ERROR;
+            }
         }
 
         ngx_http_mp4_update_stbl_atom(mp4, &trak[i]);
@@ -721,7 +739,11 @@ ngx_http_mp4_process(ngx_http_mp4_file_t *mp4)
                    "mp4 adjustment:%D", adjustment);
 
     for (i = 0; i < mp4->trak.nelts; i++) {
-        ngx_http_mp4_adjust_stco_atom(mp4, &trak[i], (int32_t) adjustment);
+        if (trak[i].out[NGX_HTTP_MP4_CO64_DATA].buf) {
+            ngx_http_mp4_adjust_co64_atom(mp4, &trak[i], adjustment);
+        } else {
+            ngx_http_mp4_adjust_stco_atom(mp4, &trak[i], (int32_t) adjustment);
+        }
     }
 
     return NGX_OK;
@@ -1702,7 +1724,6 @@ ngx_http_mp4_read_stsd_atom(ngx_http_mp4_file_t *mp4, uint64_t atom_data_size)
 {
     u_char               *atom_header, *atom_table;
     size_t                atom_size;
-    uint32_t              entries;
     ngx_buf_t            *atom;
     ngx_mp4_stsd_atom_t  *stsd_atom;
     ngx_http_mp4_trak_t  *trak;
@@ -1718,10 +1739,9 @@ ngx_http_mp4_read_stsd_atom(ngx_http_mp4_file_t *mp4, uint64_t atom_data_size)
     ngx_mp4_set_32value(stsd_atom->size, atom_size);
     ngx_mp4_set_atom_name(stsd_atom, 's', 't', 's', 'd');
 
-    entries = ngx_mp4_get_32value(stsd_atom->entries);
-
     if ((uint64_t) (sizeof(ngx_mp4_stsd_atom_t) - sizeof(ngx_mp4_atom_header_t))
-         > atom_data_size) {
+         > atom_data_size)
+    {
         ngx_log_error(NGX_LOG_ERR, mp4->file.log, 0,
                       "\"%s\" mp4 stsd atom too large",
                       mp4->file.name.data);
@@ -2497,7 +2517,7 @@ ngx_http_mp4_update_stsz_atom(ngx_http_mp4_file_t *mp4,
         }
 
         ngx_log_debug1(NGX_LOG_DEBUG_HTTP, mp4->file.log, 0,
-                       "chunk samples sizes:%uD", trak->chunk_samples_size);
+                       "chunk samples sizes:%uL", trak->chunk_samples_size);
 
         atom_size = sizeof(ngx_mp4_stsz_atom_t) + (data->last - data->pos);
         trak->size += atom_size;
@@ -2554,12 +2574,12 @@ ngx_http_mp4_read_stco_atom(ngx_http_mp4_file_t *mp4, uint64_t atom_data_size)
     trak = ngx_mp4_last_trak(mp4);
     trak->chunks = entries;
 
-    atom = &trak->tsco_atom_buf;
+    atom = &trak->stco_atom_buf;
     atom->temporary = 1;
     atom->pos = atom_header;
     atom->last = atom_table;
 
-    data = &trak->tsco_data_buf;
+    data = &trak->stco_data_buf;
     data->temporary = 1;
     data->pos = atom_table;
     data->last = atom_end;
@@ -2648,6 +2668,142 @@ ngx_http_mp4_adjust_stco_atom(ngx_http_mp4_file_t *mp4,
 }
 
 
+typedef struct {
+    u_char    size[4];
+    u_char    name[4];
+    u_char    version[1];
+    u_char    flags[3];
+    u_char    entries[4];
+} ngx_mp4_co64_atom_t;
+
+
+static ngx_int_t
+ngx_http_mp4_read_co64_atom(ngx_http_mp4_file_t *mp4, uint64_t atom_data_size)
+{
+    u_char               *atom_header, *atom_table, *atom_end;
+    uint32_t              entries;
+    ngx_buf_t            *atom, *data;
+    ngx_mp4_co64_atom_t  *co64_atom;
+    ngx_http_mp4_trak_t  *trak;
+
+    /* chunk offsets atom */
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, mp4->file.log, 0, "mp4 co64 atom");
+
+    atom_header = ngx_mp4_atom_header(mp4);
+    co64_atom = (ngx_mp4_co64_atom_t *) atom_header;
+    ngx_mp4_set_atom_name(co64_atom, 'c', 'o', '6', '4');
+
+    entries = ngx_mp4_get_32value(co64_atom->entries);
+
+    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, mp4->file.log, 0, "chunks:%uD", entries);
+
+    atom_table = atom_header + sizeof(ngx_mp4_co64_atom_t);
+    atom_end = atom_table + entries * sizeof(uint64_t);
+
+    if ((uint64_t) (atom_end - co64_atom->version) > atom_data_size) {
+        ngx_log_error(NGX_LOG_ERR, mp4->file.log, 0,
+                      "\"%s\" mp4 co64 atom too large", mp4->file.name.data);
+        return NGX_ERROR;
+    }
+
+    trak = ngx_mp4_last_trak(mp4);
+    trak->chunks = entries;
+
+    atom = &trak->co64_atom_buf;
+    atom->temporary = 1;
+    atom->pos = atom_header;
+    atom->last = atom_table;
+
+    data = &trak->co64_data_buf;
+    data->temporary = 1;
+    data->pos = atom_table;
+    data->last = atom_end;
+
+    trak->out[NGX_HTTP_MP4_CO64_ATOM].buf = atom;
+    trak->out[NGX_HTTP_MP4_CO64_DATA].buf = data;
+
+    ngx_mp4_atom_next(mp4, atom_data_size);
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_mp4_update_co64_atom(ngx_http_mp4_file_t *mp4,
+    ngx_http_mp4_trak_t *trak)
+{
+    size_t                atom_size;
+    ngx_buf_t            *atom, *data;
+    ngx_mp4_co64_atom_t  *co64_atom;
+
+    /*
+     * mdia.minf.stbl.co64 updating requires trak->start_chunk
+     * from mdia.minf.stbl.stsc which depends on value from mdia.mdhd
+     * atom which may reside after mdia.minf
+     */
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, mp4->file.log, 0,
+                   "mp4 co64 atom update");
+
+    data = trak->out[NGX_HTTP_MP4_CO64_DATA].buf;
+
+    if (data == NULL) {
+        ngx_log_error(NGX_LOG_ERR, mp4->file.log, 0,
+                      "no mp4 co64 atoms were found in \"%s\"",
+                      mp4->file.name.data);
+        return NGX_ERROR;
+    }
+
+    data->pos += trak->start_chunk * sizeof(uint64_t);
+    atom_size = sizeof(ngx_mp4_co64_atom_t) + (data->last - data->pos);
+    trak->size += atom_size;
+
+    trak->start_offset = ngx_mp4_get_64value(data->pos);
+    trak->start_offset += trak->chunk_samples_size;
+    ngx_mp4_set_64value(data->pos, trak->start_offset);
+
+    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, mp4->file.log, 0,
+                   "start chunk offset:%uL", trak->start_offset);
+
+    atom = trak->out[NGX_HTTP_MP4_CO64_ATOM].buf;
+    co64_atom = (ngx_mp4_co64_atom_t *) atom->pos;
+
+    ngx_mp4_set_32value(co64_atom->size, atom_size);
+    ngx_mp4_set_32value(co64_atom->entries, trak->chunks - trak->start_chunk);
+
+    return NGX_OK;
+}
+
+
+static void
+ngx_http_mp4_adjust_co64_atom(ngx_http_mp4_file_t *mp4,
+    ngx_http_mp4_trak_t *trak, off_t adjustment)
+{
+    uint64_t    offset, *entry, *end;
+    ngx_buf_t  *data;
+
+    /*
+     * moov.trak.mdia.minf.stbl.co64 adjustment requires
+     * minimal start offset of all traks and new moov atom size
+     */
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, mp4->file.log, 0,
+                   "mp4 co64 atom adjustment");
+
+    data = trak->out[NGX_HTTP_MP4_CO64_DATA].buf;
+    entry = (uint64_t *) data->pos;
+    end = (uint64_t *) data->last;
+
+    while (entry < end) {
+        offset = ngx_mp4_get_64value(entry);
+        offset += adjustment;
+        ngx_mp4_set_64value(entry, offset);
+        entry++;
+    }
+}
+
+
 static char *
 ngx_http_mp4(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
 {
diff --git a/src/http/modules/ngx_http_proxy_module.c b/src/http/modules/ngx_http_proxy_module.c
index 902cfb8f2..88ee42472 100644
--- a/src/http/modules/ngx_http_proxy_module.c
+++ b/src/http/modules/ngx_http_proxy_module.c
@@ -71,6 +71,8 @@ typedef struct {
 
     ngx_flag_t                     redirect;
 
+    ngx_uint_t                     http_version;
+
     ngx_uint_t                     headers_hash_max_size;
     ngx_uint_t                     headers_hash_bucket_size;
 } ngx_http_proxy_loc_conf_t;
@@ -80,6 +82,12 @@ typedef struct {
     ngx_http_status_t              status;
     ngx_http_proxy_vars_t          vars;
     size_t                         internal_body_length;
+
+    ngx_uint_t                     state;
+    off_t                          size;
+    off_t                          length;
+
+    ngx_uint_t                     head;  /* unsigned  head:1 */
 } ngx_http_proxy_ctx_t;
 
 
@@ -92,6 +100,15 @@ static ngx_int_t ngx_http_proxy_create_request(ngx_http_request_t *r);
 static ngx_int_t ngx_http_proxy_reinit_request(ngx_http_request_t *r);
 static ngx_int_t ngx_http_proxy_process_status_line(ngx_http_request_t *r);
 static ngx_int_t ngx_http_proxy_process_header(ngx_http_request_t *r);
+static ngx_int_t ngx_http_proxy_input_filter_init(void *data);
+static ngx_int_t ngx_http_proxy_copy_filter(ngx_event_pipe_t *p,
+    ngx_buf_t *buf);
+static ngx_int_t ngx_http_proxy_chunked_filter(ngx_event_pipe_t *p,
+    ngx_buf_t *buf);
+static ngx_int_t ngx_http_proxy_non_buffered_copy_filter(void *data,
+    ssize_t bytes);
+static ngx_int_t ngx_http_proxy_non_buffered_chunked_filter(void *data,
+    ssize_t bytes);
 static void ngx_http_proxy_abort_request(ngx_http_request_t *r);
 static void ngx_http_proxy_finalize_request(ngx_http_request_t *r,
     ngx_int_t rc);
@@ -157,6 +174,13 @@ static ngx_conf_bitmask_t  ngx_http_proxy_next_upstream_masks[] = {
 };
 
 
+static ngx_conf_enum_t  ngx_http_proxy_http_version[] = {
+    { ngx_string("1.0"), NGX_HTTP_VERSION_10 },
+    { ngx_string("1.1"), NGX_HTTP_VERSION_11 },
+    { ngx_null_string, 0 }
+};
+
+
 ngx_module_t  ngx_http_proxy_module;
 
 
@@ -432,6 +456,13 @@ static ngx_command_t  ngx_http_proxy_commands[] = {
       offsetof(ngx_http_proxy_loc_conf_t, upstream.ignore_headers),
       &ngx_http_upstream_ignore_headers_masks },
 
+    { ngx_string("proxy_http_version"),
+      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_enum_slot,
+      NGX_HTTP_LOC_CONF_OFFSET,
+      offsetof(ngx_http_proxy_loc_conf_t, http_version),
+      &ngx_http_proxy_http_version },
+
 #if (NGX_HTTP_SSL)
 
     { ngx_string("proxy_ssl_session_reuse"),
@@ -479,6 +510,7 @@ ngx_module_t  ngx_http_proxy_module = {
 
 
 static char  ngx_http_proxy_version[] = " HTTP/1.0" CRLF;
+static char  ngx_http_proxy_version_11[] = " HTTP/1.1" CRLF;
 
 
 static ngx_keyval_t  ngx_http_proxy_headers[] = {
@@ -486,6 +518,7 @@ static ngx_keyval_t  ngx_http_proxy_headers[] = {
     { ngx_string("Connection"), ngx_string("close") },
     { ngx_string("Keep-Alive"), ngx_string("") },
     { ngx_string("Expect"), ngx_string("") },
+    { ngx_string("Upgrade"), ngx_string("") },
     { ngx_null_string, ngx_null_string }
 };
 
@@ -610,7 +643,12 @@ ngx_http_proxy_handler(ngx_http_request_t *r)
         return NGX_HTTP_INTERNAL_SERVER_ERROR;
     }
 
-    u->pipe->input_filter = ngx_event_pipe_copy_input_filter;
+    u->pipe->input_filter = ngx_http_proxy_copy_filter;
+    u->pipe->input_ctx = r;
+
+    u->input_filter_init = ngx_http_proxy_input_filter_init;
+    u->input_filter = ngx_http_proxy_non_buffered_copy_filter;
+    u->input_filter_ctx = r;
 
     u->accel = 1;
 
@@ -866,14 +904,20 @@ ngx_http_proxy_create_request(ngx_http_request_t *r)
         method.len++;
     }
 
+    ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
+
+    if (method.len == 5
+        && ngx_strncasecmp(method.data, (u_char *) "HEAD ", 5) == 0)
+    {
+        ctx->head = 1;
+    }
+
     len = method.len + sizeof(ngx_http_proxy_version) - 1 + sizeof(CRLF) - 1;
 
     escape = 0;
     loc_len = 0;
     unparsed_uri = 0;
 
-    ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
-
     if (plcf->proxy_lengths) {
         uri_len = ctx->vars.uri.len;
 
@@ -1009,8 +1053,14 @@ ngx_http_proxy_create_request(ngx_http_request_t *r)
 
     u->uri.len = b->last - u->uri.data;
 
-    b->last = ngx_cpymem(b->last, ngx_http_proxy_version,
-                         sizeof(ngx_http_proxy_version) - 1);
+    if (plcf->http_version == NGX_HTTP_VERSION_11) {
+        b->last = ngx_cpymem(b->last, ngx_http_proxy_version_11,
+                             sizeof(ngx_http_proxy_version_11) - 1);
+
+    } else {
+        b->last = ngx_cpymem(b->last, ngx_http_proxy_version,
+                             sizeof(ngx_http_proxy_version) - 1);
+    }
 
     ngx_memzero(&e, sizeof(ngx_http_script_engine_t));
 
@@ -1158,8 +1208,11 @@ ngx_http_proxy_reinit_request(ngx_http_request_t *r)
     ctx->status.count = 0;
     ctx->status.start = NULL;
     ctx->status.end = NULL;
+    ctx->state = 0;
 
     r->upstream->process_header = ngx_http_proxy_process_status_line;
+    r->upstream->pipe->input_filter = ngx_http_proxy_copy_filter;
+    r->upstream->input_filter = ngx_http_proxy_non_buffered_copy_filter;
     r->state = 0;
 
     return NGX_OK;
@@ -1210,6 +1263,7 @@ ngx_http_proxy_process_status_line(ngx_http_request_t *r)
 
         r->http_version = NGX_HTTP_VERSION_9;
         u->state->status = NGX_HTTP_OK;
+        u->headers_in.connection_close = 1;
 
         return NGX_OK;
     }
@@ -1234,6 +1288,10 @@ ngx_http_proxy_process_status_line(ngx_http_request_t *r)
                    "http proxy status %ui \"%V\"",
                    u->headers_in.status_n, &u->headers_in.status_line);
 
+    if (ctx->status.http_version < NGX_HTTP_VERSION_11) {
+        u->headers_in.connection_close = 1;
+    }
+
     u->process_header = ngx_http_proxy_process_header;
 
     return ngx_http_proxy_process_header(r);
@@ -1245,6 +1303,8 @@ ngx_http_proxy_process_header(ngx_http_request_t *r)
 {
     ngx_int_t                       rc;
     ngx_table_elt_t                *h;
+    ngx_http_upstream_t            *u;
+    ngx_http_proxy_ctx_t           *ctx;
     ngx_http_upstream_header_t     *hh;
     ngx_http_upstream_main_conf_t  *umcf;
 
@@ -1340,6 +1400,30 @@ ngx_http_proxy_process_header(ngx_http_request_t *r)
                 h->lowcase_key = (u_char *) "date";
             }
 
+            /* clear content length if response is chunked */
+
+            u = r->upstream;
+
+            if (u->headers_in.chunked) {
+                u->headers_in.content_length_n = -1;
+            }
+
+            /*
+             * set u->keepalive if response has no body; this allows to keep
+             * connections alive in case of r->header_only or X-Accel-Redirect
+             */
+
+            ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
+
+            if (u->headers_in.status_n == NGX_HTTP_NO_CONTENT
+                || u->headers_in.status_n == NGX_HTTP_NOT_MODIFIED
+                || ctx->head
+                || (!u->headers_in.chunked
+                    && u->headers_in.content_length_n == 0))
+            {
+                u->keepalive = !u->headers_in.connection_close;
+            }
+
             return NGX_OK;
         }
 
@@ -1357,6 +1441,690 @@ ngx_http_proxy_process_header(ngx_http_request_t *r)
 }
 
 
+static ngx_int_t
+ngx_http_proxy_input_filter_init(void *data)
+{
+    ngx_http_request_t    *r = data;
+    ngx_http_upstream_t   *u;
+    ngx_http_proxy_ctx_t  *ctx;
+
+    u = r->upstream;
+    ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
+
+    ngx_log_debug4(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
+                   "http proxy filter init s:%d h:%d c:%d l:%O",
+                   u->headers_in.status_n, ctx->head, u->headers_in.chunked,
+                   u->headers_in.content_length_n);
+
+    /* as per RFC2616, 4.4 Message Length */
+
+    if (u->headers_in.status_n == NGX_HTTP_NO_CONTENT
+        || u->headers_in.status_n == NGX_HTTP_NOT_MODIFIED
+        || ctx->head)
+    {
+        /* 1xx, 204, and 304 and replies to HEAD requests */
+        /* no 1xx since we don't send Expect and Upgrade */
+
+        u->pipe->length = 0;
+        u->length = 0;
+        u->keepalive = !u->headers_in.connection_close;
+
+    } else if (u->headers_in.chunked) {
+        /* chunked */
+
+        u->pipe->input_filter = ngx_http_proxy_chunked_filter;
+        u->pipe->length = 3; /* "0" LF LF */
+
+        u->input_filter = ngx_http_proxy_non_buffered_chunked_filter;
+        u->length = -1;
+
+    } else if (u->headers_in.content_length_n == 0) {
+        /* empty body: special case as filter won't be called */
+
+        u->pipe->length = 0;
+        u->length = 0;
+        u->keepalive = !u->headers_in.connection_close;
+
+    } else {
+        /* content length or connection close */
+
+        u->pipe->length = u->headers_in.content_length_n;
+        u->length = u->headers_in.content_length_n;
+    }
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_proxy_copy_filter(ngx_event_pipe_t *p, ngx_buf_t *buf)
+{
+    ngx_buf_t           *b;
+    ngx_chain_t         *cl;
+    ngx_http_request_t  *r;
+
+    if (buf->pos == buf->last) {
+        return NGX_OK;
+    }
+
+    if (p->free) {
+        cl = p->free;
+        b = cl->buf;
+        p->free = cl->next;
+        ngx_free_chain(p->pool, cl);
+
+    } else {
+        b = ngx_alloc_buf(p->pool);
+        if (b == NULL) {
+            return NGX_ERROR;
+        }
+    }
+
+    ngx_memcpy(b, buf, sizeof(ngx_buf_t));
+    b->shadow = buf;
+    b->tag = p->tag;
+    b->last_shadow = 1;
+    b->recycled = 1;
+    buf->shadow = b;
+
+    cl = ngx_alloc_chain_link(p->pool);
+    if (cl == NULL) {
+        return NGX_ERROR;
+    }
+
+    cl->buf = b;
+    cl->next = NULL;
+
+    ngx_log_debug1(NGX_LOG_DEBUG_EVENT, p->log, 0, "input buf #%d", b->num);
+
+    if (p->in) {
+        *p->last_in = cl;
+    } else {
+        p->in = cl;
+    }
+    p->last_in = &cl->next;
+
+    if (p->length == -1) {
+        return NGX_OK;
+    }
+
+    p->length -= b->last - b->pos;
+
+    if (p->length == 0) {
+        r = p->input_ctx;
+        p->upstream_done = 1;
+        r->upstream->keepalive = !r->upstream->headers_in.connection_close;
+
+    } else if (p->length < 0) {
+        r = p->input_ctx;
+        p->upstream_done = 1;
+
+        ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
+                      "upstream sent too many data");
+    }
+
+    return NGX_OK;
+}
+
+
+static ngx_inline ngx_int_t
+ngx_http_proxy_parse_chunked(ngx_http_request_t *r, ngx_buf_t *buf)
+{
+    u_char                *pos, ch, c;
+    ngx_int_t              rc;
+    ngx_http_proxy_ctx_t  *ctx;
+    enum {
+        sw_chunk_start = 0,
+        sw_chunk_size,
+        sw_chunk_extension,
+        sw_chunk_extension_almost_done,
+        sw_chunk_data,
+        sw_after_data,
+        sw_after_data_almost_done,
+        sw_last_chunk_extension,
+        sw_last_chunk_extension_almost_done,
+        sw_trailer,
+        sw_trailer_almost_done,
+        sw_trailer_header,
+        sw_trailer_header_almost_done
+    } state;
+
+    ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
+    state = ctx->state;
+
+    if (state == sw_chunk_data && ctx->size == 0) {
+        state = sw_after_data;
+    }
+
+    rc = NGX_AGAIN;
+
+    for (pos = buf->pos; pos < buf->last; pos++) {
+
+        ch = *pos;
+
+        ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
+                       "http proxy chunked byte: %02Xd s:%d", ch, state);
+
+        switch (state) {
+
+        case sw_chunk_start:
+            if (ch >= '0' && ch <= '9') {
+                state = sw_chunk_size;
+                ctx->size = ch - '0';
+                break;
+            }
+
+            c = (u_char) (ch | 0x20);
+
+            if (c >= 'a' && c <= 'f') {
+                state = sw_chunk_size;
+                ctx->size = c - 'a' + 10;
+                break;
+            }
+
+            goto invalid;
+
+        case sw_chunk_size:
+            if (ch >= '0' && ch <= '9') {
+                ctx->size = ctx->size * 16 + (ch - '0');
+                break;
+            }
+
+            c = (u_char) (ch | 0x20);
+
+            if (c >= 'a' && c <= 'f') {
+                ctx->size = ctx->size * 16 + (c - 'a' + 10);
+                break;
+            }
+
+            if (ctx->size == 0) {
+
+                switch (ch) {
+                case CR:
+                    state = sw_last_chunk_extension_almost_done;
+                    break;
+                case LF:
+                    state = sw_trailer;
+                    break;
+                case ';':
+                    state = sw_last_chunk_extension;
+                    break;
+                default:
+                    goto invalid;
+                }
+
+                break;
+            }
+
+            switch (ch) {
+            case CR:
+                state = sw_chunk_extension_almost_done;
+                break;
+            case LF:
+                state = sw_chunk_data;
+                break;
+            case ';':
+                state = sw_chunk_extension;
+                break;
+            default:
+                goto invalid;
+            }
+
+            break;
+
+        case sw_chunk_extension:
+            switch (ch) {
+            case CR:
+                state = sw_chunk_extension_almost_done;
+                break;
+            case LF:
+                state = sw_chunk_data;
+            }
+            break;
+
+        case sw_chunk_extension_almost_done:
+            if (ch == LF) {
+                state = sw_chunk_data;
+                break;
+            }
+            goto invalid;
+
+        case sw_chunk_data:
+            rc = NGX_OK;
+            goto data;
+
+        case sw_after_data:
+            switch (ch) {
+            case CR:
+                state = sw_after_data_almost_done;
+                break;
+            case LF:
+                state = sw_chunk_start;
+            }
+            break;
+
+        case sw_after_data_almost_done:
+            if (ch == LF) {
+                state = sw_chunk_start;
+                break;
+            }
+            goto invalid;
+
+        case sw_last_chunk_extension:
+            switch (ch) {
+            case CR:
+                state = sw_last_chunk_extension_almost_done;
+                break;
+            case LF:
+                state = sw_trailer;
+            }
+            break;
+
+        case sw_last_chunk_extension_almost_done:
+            if (ch == LF) {
+                state = sw_trailer;
+                break;
+            }
+            goto invalid;
+
+        case sw_trailer:
+            switch (ch) {
+            case CR:
+                state = sw_trailer_almost_done;
+                break;
+            case LF:
+                goto done;
+            default:
+                state = sw_trailer_header;
+            }
+            break;
+
+        case sw_trailer_almost_done:
+            if (ch == LF) {
+                goto done;
+            }
+            goto invalid;
+
+        case sw_trailer_header:
+            switch (ch) {
+            case CR:
+                state = sw_trailer_header_almost_done;
+                break;
+            case LF:
+                state = sw_trailer;
+            }
+            break;
+
+        case sw_trailer_header_almost_done:
+            if (ch == LF) {
+                state = sw_trailer;
+                break;
+            }
+            goto invalid;
+
+        }
+    }
+
+data:
+
+    ctx->state = state;
+    buf->pos = pos;
+
+    switch (state) {
+
+    case sw_chunk_start:
+        ctx->length = 3 /* "0" LF LF */;
+        break;
+    case sw_chunk_size:
+        ctx->length = 2 /* LF LF */
+                      + (ctx->size ? ctx->size + 4 /* LF "0" LF LF */ : 0);
+        break;
+    case sw_chunk_extension:
+    case sw_chunk_extension_almost_done:
+        ctx->length = 1 /* LF */ + ctx->size + 4 /* LF "0" LF LF */;
+        break;
+    case sw_chunk_data:
+        ctx->length = ctx->size + 4 /* LF "0" LF LF */;
+        break;
+    case sw_after_data:
+    case sw_after_data_almost_done:
+        ctx->length = 4 /* LF "0" LF LF */;
+        break;
+    case sw_last_chunk_extension:
+    case sw_last_chunk_extension_almost_done:
+        ctx->length = 2 /* LF LF */;
+        break;
+    case sw_trailer:
+    case sw_trailer_almost_done:
+        ctx->length = 1 /* LF */;
+        break;
+    case sw_trailer_header:
+    case sw_trailer_header_almost_done:
+        ctx->length = 2 /* LF LF */;
+        break;
+
+    }
+
+    return rc;
+
+done:
+
+    return NGX_DONE;
+
+invalid:
+
+    ngx_log_error(NGX_LOG_ALERT, r->connection->log, 0,
+                  "upstream sent invalid chunked response");
+
+    return NGX_ERROR;
+}
+
+
+static ngx_int_t
+ngx_http_proxy_chunked_filter(ngx_event_pipe_t *p, ngx_buf_t *buf)
+{
+    ngx_int_t              rc;
+    ngx_buf_t             *b, **prev;
+    ngx_chain_t           *cl;
+    ngx_http_request_t    *r;
+    ngx_http_proxy_ctx_t  *ctx;
+
+    if (buf->pos == buf->last) {
+        return NGX_OK;
+    }
+
+    r = p->input_ctx;
+    ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
+
+    b = NULL;
+    prev = &buf->shadow;
+
+    for ( ;; ) {
+
+        rc = ngx_http_proxy_parse_chunked(r, buf);
+
+        if (rc == NGX_OK) {
+
+            /* a chunk has been parsed successfully */
+
+            if (p->free) {
+                cl = p->free;
+                b = cl->buf;
+                p->free = cl->next;
+                ngx_free_chain(p->pool, cl);
+
+            } else {
+                b = ngx_alloc_buf(p->pool);
+                if (b == NULL) {
+                    return NGX_ERROR;
+                }
+            }
+
+            ngx_memzero(b, sizeof(ngx_buf_t));
+
+            b->pos = buf->pos;
+            b->start = buf->start;
+            b->end = buf->end;
+            b->tag = p->tag;
+            b->temporary = 1;
+            b->recycled = 1;
+
+            *prev = b;
+            prev = &b->shadow;
+
+            cl = ngx_alloc_chain_link(p->pool);
+            if (cl == NULL) {
+                return NGX_ERROR;
+            }
+
+            cl->buf = b;
+            cl->next = NULL;
+
+            if (p->in) {
+                *p->last_in = cl;
+            } else {
+                p->in = cl;
+            }
+            p->last_in = &cl->next;
+
+            /* STUB */ b->num = buf->num;
+
+            ngx_log_debug2(NGX_LOG_DEBUG_EVENT, p->log, 0,
+                           "input buf #%d %p", b->num, b->pos);
+
+            if (buf->last - buf->pos >= ctx->size) {
+
+                buf->pos += ctx->size;
+                b->last = buf->pos;
+                ctx->size = 0;
+
+                continue;
+            }
+
+            ctx->size -= buf->last - buf->pos;
+            buf->pos = buf->last;
+            b->last = buf->last;
+
+            continue;
+        }
+
+        if (rc == NGX_DONE) {
+
+            /* a whole response has been parsed successfully */
+
+            p->upstream_done = 1;
+            r->upstream->keepalive = !r->upstream->headers_in.connection_close;
+
+            break;
+        }
+
+        if (rc == NGX_AGAIN) {
+
+            /* set p->length, minimal amount of data we want to see */
+
+            p->length = ctx->length;
+
+            break;
+        }
+
+        /* invalid response */
+
+        ngx_log_error(NGX_LOG_ALERT, r->connection->log, 0,
+                      "upstream sent invalid chunked response");
+
+        return NGX_ERROR;
+    }
+
+    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
+                   "http proxy chunked state %d, length %d",
+                   ctx->state, p->length);
+
+    if (b) {
+        b->shadow = buf;
+        b->last_shadow = 1;
+
+        ngx_log_debug2(NGX_LOG_DEBUG_EVENT, p->log, 0,
+                       "input buf %p %z", b->pos, b->last - b->pos);
+
+        return NGX_OK;
+    }
+
+    /* there is no data record in the buf, add it to free chain */
+
+    if (ngx_event_pipe_add_free_buf(p, buf) != NGX_OK) {
+        return NGX_ERROR;
+    }
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_proxy_non_buffered_copy_filter(void *data, ssize_t bytes)
+{
+    ngx_http_request_t   *r = data;
+
+    ngx_buf_t            *b;
+    ngx_chain_t          *cl, **ll;
+    ngx_http_upstream_t  *u;
+
+    u = r->upstream;
+
+    for (cl = u->out_bufs, ll = &u->out_bufs; cl; cl = cl->next) {
+        ll = &cl->next;
+    }
+
+    cl = ngx_chain_get_free_buf(r->pool, &u->free_bufs);
+    if (cl == NULL) {
+        return NGX_ERROR;
+    }
+
+    *ll = cl;
+
+    cl->buf->flush = 1;
+    cl->buf->memory = 1;
+
+    b = &u->buffer;
+
+    cl->buf->pos = b->last;
+    b->last += bytes;
+    cl->buf->last = b->last;
+    cl->buf->tag = u->output.tag;
+
+    if (u->length == -1) {
+        return NGX_OK;
+    }
+
+    u->length -= bytes;
+
+    if (u->length == 0) {
+        u->keepalive = !u->headers_in.connection_close;
+    }
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_proxy_non_buffered_chunked_filter(void *data, ssize_t bytes)
+{
+    ngx_http_request_t   *r = data;
+
+    ngx_int_t              rc;
+    ngx_buf_t             *b, *buf;
+    ngx_chain_t           *cl, **ll;
+    ngx_http_upstream_t   *u;
+    ngx_http_proxy_ctx_t  *ctx;
+
+    ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
+    u = r->upstream;
+    buf = &u->buffer;
+
+    buf->pos = buf->last;
+    buf->last += bytes;
+
+    for (cl = u->out_bufs, ll = &u->out_bufs; cl; cl = cl->next) {
+        ll = &cl->next;
+    }
+
+    for ( ;; ) {
+
+        rc = ngx_http_proxy_parse_chunked(r, buf);
+
+        if (rc == NGX_OK) {
+
+            /* a chunk has been parsed successfully */
+
+            cl = ngx_chain_get_free_buf(r->pool, &u->free_bufs);
+            if (cl == NULL) {
+                return NGX_ERROR;
+            }
+
+            *ll = cl;
+            ll = &cl->next;
+
+            b = cl->buf;
+
+            b->flush = 1;
+            b->memory = 1;
+
+            b->pos = buf->pos;
+            b->tag = u->output.tag;
+
+            if (buf->last - buf->pos >= ctx->size) {
+                buf->pos += ctx->size;
+                b->last = buf->pos;
+                ctx->size = 0;
+
+            } else {
+                ctx->size -= buf->last - buf->pos;
+                buf->pos = buf->last;
+                b->last = buf->last;
+            }
+
+            ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
+                           "http proxy out buf %p %z",
+                           b->pos, b->last - b->pos);
+
+            continue;
+        }
+
+        if (rc == NGX_DONE) {
+
+            /* a whole response has been parsed successfully */
+
+            u->keepalive = !u->headers_in.connection_close;
+            u->length = 0;
+
+            break;
+        }
+
+        if (rc == NGX_AGAIN) {
+            break;
+        }
+
+        /* invalid response */
+
+        ngx_log_error(NGX_LOG_ALERT, r->connection->log, 0,
+                      "upstream sent invalid chunked response");
+
+        return NGX_ERROR;
+    }
+
+    /* provide continuous buffer for subrequests in memory */
+
+    if (r->subrequest_in_memory) {
+
+        cl = u->out_bufs;
+
+        if (cl) {
+            buf->pos = cl->buf->pos;
+        }
+
+        buf->last = buf->pos;
+
+        for (cl = u->out_bufs; cl; cl = cl->next) {
+            ngx_log_debug3(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
+                           "http proxy in memory %p-%p %uz",
+                           cl->buf->pos, cl->buf->last, ngx_buf_size(cl->buf));
+
+            if (buf->last == cl->buf->pos) {
+                buf->last = cl->buf->last;
+                continue;
+            }
+
+            buf->last = ngx_movemem(buf->last, cl->buf->pos,
+                                    cl->buf->last - cl->buf->pos);
+
+            cl->buf->pos = buf->last - (cl->buf->last - cl->buf->pos);
+            cl->buf->last = buf->last;
+        }
+    }
+
+    return NGX_OK;
+}
+
+
 static void
 ngx_http_proxy_abort_request(ngx_http_request_t *r)
 {
@@ -1705,6 +2473,8 @@ ngx_http_proxy_create_loc_conf(ngx_conf_t *cf)
     conf->redirect = NGX_CONF_UNSET;
     conf->upstream.change_buffering = 1;
 
+    conf->http_version = NGX_CONF_UNSET_UINT;
+
     conf->headers_hash_max_size = NGX_CONF_UNSET_UINT;
     conf->headers_hash_bucket_size = NGX_CONF_UNSET_UINT;
 
@@ -2008,6 +2778,9 @@ ngx_http_proxy_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
     }
 #endif
 
+    ngx_conf_merge_uint_value(conf->http_version, prev->http_version,
+                              NGX_HTTP_VERSION_10);
+
     ngx_conf_merge_uint_value(conf->headers_hash_max_size,
                               prev->headers_hash_max_size, 512);
 
diff --git a/src/http/modules/ngx_http_upstream_keepalive_module.c b/src/http/modules/ngx_http_upstream_keepalive_module.c
new file mode 100644
index 000000000..945f78b15
--- /dev/null
+++ b/src/http/modules/ngx_http_upstream_keepalive_module.c
@@ -0,0 +1,569 @@
+
+/*
+ * Copyright (C) Maxim Dounin
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_http.h>
+
+
+typedef struct {
+    ngx_uint_t                         max_cached;
+    ngx_uint_t                         single;       /* unsigned:1 */
+
+    ngx_queue_t                        cache;
+    ngx_queue_t                        free;
+
+    ngx_http_upstream_init_pt          original_init_upstream;
+    ngx_http_upstream_init_peer_pt     original_init_peer;
+
+} ngx_http_upstream_keepalive_srv_conf_t;
+
+
+typedef struct {
+    ngx_http_upstream_keepalive_srv_conf_t  *conf;
+
+    ngx_http_upstream_t               *upstream;
+
+    void                              *data;
+
+    ngx_event_get_peer_pt              original_get_peer;
+    ngx_event_free_peer_pt             original_free_peer;
+
+#if (NGX_HTTP_SSL)
+    ngx_event_set_peer_session_pt      original_set_session;
+    ngx_event_save_peer_session_pt     original_save_session;
+#endif
+
+    ngx_uint_t                         failed;       /* unsigned:1 */
+
+} ngx_http_upstream_keepalive_peer_data_t;
+
+
+typedef struct {
+    ngx_http_upstream_keepalive_srv_conf_t  *conf;
+
+    ngx_queue_t                        queue;
+    ngx_connection_t                  *connection;
+
+    socklen_t                          socklen;
+    u_char                             sockaddr[NGX_SOCKADDRLEN];
+
+} ngx_http_upstream_keepalive_cache_t;
+
+
+static ngx_int_t ngx_http_upstream_init_keepalive_peer(ngx_http_request_t *r,
+    ngx_http_upstream_srv_conf_t *us);
+static ngx_int_t ngx_http_upstream_get_keepalive_peer(ngx_peer_connection_t *pc,
+    void *data);
+static void ngx_http_upstream_free_keepalive_peer(ngx_peer_connection_t *pc,
+    void *data, ngx_uint_t state);
+
+static void ngx_http_upstream_keepalive_dummy_handler(ngx_event_t *ev);
+static void ngx_http_upstream_keepalive_close_handler(ngx_event_t *ev);
+static void ngx_http_upstream_keepalive_close(ngx_connection_t *c);
+
+
+#if (NGX_HTTP_SSL)
+static ngx_int_t ngx_http_upstream_keepalive_set_session(
+    ngx_peer_connection_t *pc, void *data);
+static void ngx_http_upstream_keepalive_save_session(ngx_peer_connection_t *pc,
+    void *data);
+#endif
+
+static void *ngx_http_upstream_keepalive_create_conf(ngx_conf_t *cf);
+static char *ngx_http_upstream_keepalive(ngx_conf_t *cf, ngx_command_t *cmd,
+    void *conf);
+
+
+static ngx_command_t  ngx_http_upstream_keepalive_commands[] = {
+
+    { ngx_string("keepalive"),
+      NGX_HTTP_UPS_CONF|NGX_CONF_TAKE12,
+      ngx_http_upstream_keepalive,
+      0,
+      0,
+      NULL },
+
+      ngx_null_command
+};
+
+
+static ngx_http_module_t  ngx_http_upstream_keepalive_module_ctx = {
+    NULL,                                  /* preconfiguration */
+    NULL,                                  /* postconfiguration */
+
+    NULL,                                  /* create main configuration */
+    NULL,                                  /* init main configuration */
+
+    ngx_http_upstream_keepalive_create_conf, /* create server configuration */
+    NULL,                                  /* merge server configuration */
+
+    NULL,                                  /* create location configuration */
+    NULL                                   /* merge location configuration */
+};
+
+
+ngx_module_t  ngx_http_upstream_keepalive_module = {
+    NGX_MODULE_V1,
+    &ngx_http_upstream_keepalive_module_ctx, /* module context */
+    ngx_http_upstream_keepalive_commands,    /* module directives */
+    NGX_HTTP_MODULE,                       /* module type */
+    NULL,                                  /* init master */
+    NULL,                                  /* init module */
+    NULL,                                  /* init process */
+    NULL,                                  /* init thread */
+    NULL,                                  /* exit thread */
+    NULL,                                  /* exit process */
+    NULL,                                  /* exit master */
+    NGX_MODULE_V1_PADDING
+};
+
+
+static ngx_int_t
+ngx_http_upstream_init_keepalive(ngx_conf_t *cf,
+    ngx_http_upstream_srv_conf_t *us)
+{
+    ngx_uint_t                               i;
+    ngx_http_upstream_keepalive_srv_conf_t  *kcf;
+    ngx_http_upstream_keepalive_cache_t     *cached;
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, cf->log, 0,
+                   "init keepalive");
+
+    kcf = ngx_http_conf_upstream_srv_conf(us,
+                                          ngx_http_upstream_keepalive_module);
+
+    if (kcf->original_init_upstream(cf, us) != NGX_OK) {
+        return NGX_ERROR;
+    }
+
+    kcf->original_init_peer = us->peer.init;
+
+    us->peer.init = ngx_http_upstream_init_keepalive_peer;
+
+    /* allocate cache items and add to free queue */
+
+    cached = ngx_pcalloc(cf->pool,
+                sizeof(ngx_http_upstream_keepalive_cache_t) * kcf->max_cached);
+    if (cached == NULL) {
+        return NGX_ERROR;
+    }
+
+    ngx_queue_init(&kcf->cache);
+    ngx_queue_init(&kcf->free);
+
+    for (i = 0; i < kcf->max_cached; i++) {
+        ngx_queue_insert_head(&kcf->free, &cached[i].queue);
+        cached[i].conf = kcf;
+    }
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_upstream_init_keepalive_peer(ngx_http_request_t *r,
+    ngx_http_upstream_srv_conf_t *us)
+{
+    ngx_http_upstream_keepalive_peer_data_t  *kp;
+    ngx_http_upstream_keepalive_srv_conf_t   *kcf;
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
+                   "init keepalive peer");
+
+    kcf = ngx_http_conf_upstream_srv_conf(us,
+                                          ngx_http_upstream_keepalive_module);
+
+    kp = ngx_palloc(r->pool, sizeof(ngx_http_upstream_keepalive_peer_data_t));
+    if (kp == NULL) {
+        return NGX_ERROR;
+    }
+
+    if (kcf->original_init_peer(r, us) != NGX_OK) {
+        return NGX_ERROR;
+    }
+
+    kp->conf = kcf;
+    kp->upstream = r->upstream;
+    kp->data = r->upstream->peer.data;
+    kp->original_get_peer = r->upstream->peer.get;
+    kp->original_free_peer = r->upstream->peer.free;
+
+    r->upstream->peer.data = kp;
+    r->upstream->peer.get = ngx_http_upstream_get_keepalive_peer;
+    r->upstream->peer.free = ngx_http_upstream_free_keepalive_peer;
+
+#if (NGX_HTTP_SSL)
+    kp->original_set_session = r->upstream->peer.set_session;
+    kp->original_save_session = r->upstream->peer.save_session;
+    r->upstream->peer.set_session = ngx_http_upstream_keepalive_set_session;
+    r->upstream->peer.save_session = ngx_http_upstream_keepalive_save_session;
+#endif
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_upstream_get_keepalive_peer(ngx_peer_connection_t *pc, void *data)
+{
+    ngx_http_upstream_keepalive_peer_data_t  *kp = data;
+    ngx_http_upstream_keepalive_cache_t      *item;
+
+    ngx_int_t          rc;
+    ngx_queue_t       *q, *cache;
+    ngx_connection_t  *c;
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, pc->log, 0,
+                   "get keepalive peer");
+
+    kp->failed = 0;
+
+    /* single pool of cached connections */
+
+    if (kp->conf->single && !ngx_queue_empty(&kp->conf->cache)) {
+
+        q = ngx_queue_head(&kp->conf->cache);
+
+        item = ngx_queue_data(q, ngx_http_upstream_keepalive_cache_t, queue);
+        c = item->connection;
+
+        ngx_queue_remove(q);
+        ngx_queue_insert_head(&kp->conf->free, q);
+
+        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0,
+                       "get keepalive peer: using connection %p", c);
+
+        c->idle = 0;
+        c->log = pc->log;
+        c->read->log = pc->log;
+        c->write->log = pc->log;
+        c->pool->log = pc->log;
+
+        pc->connection = c;
+        pc->cached = 1;
+
+        return NGX_DONE;
+    }
+
+    rc = kp->original_get_peer(pc, kp->data);
+
+    if (kp->conf->single || rc != NGX_OK) {
+        return rc;
+    }
+
+    /* search cache for suitable connection */
+
+    cache = &kp->conf->cache;
+
+    for (q = ngx_queue_head(cache);
+         q != ngx_queue_sentinel(cache);
+         q = ngx_queue_next(q))
+    {
+        item = ngx_queue_data(q, ngx_http_upstream_keepalive_cache_t, queue);
+        c = item->connection;
+
+        if (ngx_memn2cmp((u_char *) &item->sockaddr, (u_char *) pc->sockaddr,
+                         item->socklen, pc->socklen)
+            == 0)
+        {
+            ngx_queue_remove(q);
+            ngx_queue_insert_head(&kp->conf->free, q);
+
+            ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0,
+                           "get keepalive peer: using connection %p", c);
+
+            c->idle = 0;
+            c->log = pc->log;
+            c->read->log = pc->log;
+            c->write->log = pc->log;
+            c->pool->log = pc->log;
+
+            pc->connection = c;
+            pc->cached = 1;
+
+            return NGX_DONE;
+        }
+    }
+
+    return NGX_OK;
+}
+
+
+static void
+ngx_http_upstream_free_keepalive_peer(ngx_peer_connection_t *pc, void *data,
+    ngx_uint_t state)
+{
+    ngx_http_upstream_keepalive_peer_data_t  *kp = data;
+    ngx_http_upstream_keepalive_cache_t      *item;
+
+    ngx_queue_t          *q;
+    ngx_connection_t     *c;
+    ngx_http_upstream_t  *u;
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, pc->log, 0,
+                   "free keepalive peer");
+
+    /* remember failed state - peer.free() may be called more than once */
+
+    if (state & NGX_PEER_FAILED) {
+        kp->failed = 1;
+    }
+
+    /* cache valid connections */
+
+    u = kp->upstream;
+    c = pc->connection;
+
+    if (kp->failed
+        || c == NULL
+        || c->read->eof
+        || c->read->error
+        || c->read->timedout
+        || c->write->error
+        || c->write->timedout)
+    {
+        goto invalid;
+    }
+
+    if (!u->keepalive) {
+        goto invalid;
+    }
+
+    if (ngx_handle_read_event(c->read, 0) != NGX_OK) {
+        goto invalid;
+    }
+
+    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0,
+                   "free keepalive peer: saving connection %p", c);
+
+    if (ngx_queue_empty(&kp->conf->free)) {
+
+        q = ngx_queue_last(&kp->conf->cache);
+        ngx_queue_remove(q);
+
+        item = ngx_queue_data(q, ngx_http_upstream_keepalive_cache_t, queue);
+
+        ngx_http_upstream_keepalive_close(item->connection);
+
+    } else {
+        q = ngx_queue_head(&kp->conf->free);
+        ngx_queue_remove(q);
+
+        item = ngx_queue_data(q, ngx_http_upstream_keepalive_cache_t, queue);
+    }
+
+    item->connection = c;
+    ngx_queue_insert_head(&kp->conf->cache, q);
+
+    pc->connection = NULL;
+
+    if (c->read->timer_set) {
+        ngx_del_timer(c->read);
+    }
+    if (c->write->timer_set) {
+        ngx_del_timer(c->write);
+    }
+
+    c->write->handler = ngx_http_upstream_keepalive_dummy_handler;
+    c->read->handler = ngx_http_upstream_keepalive_close_handler;
+
+    c->data = item;
+    c->idle = 1;
+    c->log = ngx_cycle->log;
+    c->read->log = ngx_cycle->log;
+    c->write->log = ngx_cycle->log;
+    c->pool->log = ngx_cycle->log;
+
+    item->socklen = pc->socklen;
+    ngx_memcpy(&item->sockaddr, pc->sockaddr, pc->socklen);
+
+    if (c->read->ready) {
+        ngx_http_upstream_keepalive_close_handler(c->read);
+    }
+
+invalid:
+
+    kp->original_free_peer(pc, kp->data, state);
+}
+
+
+static void
+ngx_http_upstream_keepalive_dummy_handler(ngx_event_t *ev)
+{
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, ev->log, 0,
+                   "keepalive dummy handler");
+}
+
+
+static void
+ngx_http_upstream_keepalive_close_handler(ngx_event_t *ev)
+{
+    ngx_http_upstream_keepalive_srv_conf_t  *conf;
+    ngx_http_upstream_keepalive_cache_t     *item;
+
+    int                n;
+    char               buf[1];
+    ngx_connection_t  *c;
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, ev->log, 0,
+                   "keepalive close handler");
+
+    c = ev->data;
+
+    if (c->close) {
+        goto close;
+    }
+
+    n = recv(c->fd, buf, 1, MSG_PEEK);
+
+    if (n == -1 && ngx_socket_errno == NGX_EAGAIN) {
+        /* stale event */
+
+        if (ngx_handle_read_event(c->read, 0) != NGX_OK) {
+            goto close;
+        }
+
+        return;
+    }
+
+close:
+
+    item = c->data;
+    conf = item->conf;
+
+    ngx_http_upstream_keepalive_close(c);
+
+    ngx_queue_remove(&item->queue);
+    ngx_queue_insert_head(&conf->free, &item->queue);
+}
+
+
+static void
+ngx_http_upstream_keepalive_close(ngx_connection_t *c)
+{
+
+#if (NGX_HTTP_SSL)
+
+    if (c->ssl) {
+        c->ssl->no_wait_shutdown = 1;
+        c->ssl->no_send_shutdown = 1;
+
+        if (ngx_ssl_shutdown(c) == NGX_AGAIN) {
+            c->ssl->handler = ngx_http_upstream_keepalive_close;
+            return;
+        }
+    }
+
+#endif
+
+    ngx_destroy_pool(c->pool);
+    ngx_close_connection(c);
+}
+
+
+#if (NGX_HTTP_SSL)
+
+static ngx_int_t
+ngx_http_upstream_keepalive_set_session(ngx_peer_connection_t *pc, void *data)
+{
+    ngx_http_upstream_keepalive_peer_data_t  *kp = data;
+
+    return kp->original_set_session(pc, kp->data);
+}
+
+
+static void
+ngx_http_upstream_keepalive_save_session(ngx_peer_connection_t *pc, void *data)
+{
+    ngx_http_upstream_keepalive_peer_data_t  *kp = data;
+
+    kp->original_save_session(pc, kp->data);
+    return;
+}
+
+#endif
+
+
+static void *
+ngx_http_upstream_keepalive_create_conf(ngx_conf_t *cf)
+{
+    ngx_http_upstream_keepalive_srv_conf_t  *conf;
+
+    conf = ngx_pcalloc(cf->pool,
+                       sizeof(ngx_http_upstream_keepalive_srv_conf_t));
+    if (conf == NULL) {
+        return NULL;
+    }
+
+    /*
+     * set by ngx_pcalloc():
+     *
+     *     conf->original_init_upstream = NULL;
+     *     conf->original_init_peer = NULL;
+     */
+
+    conf->max_cached = 1;
+
+    return conf;
+}
+
+
+static char *
+ngx_http_upstream_keepalive(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
+{
+    ngx_http_upstream_srv_conf_t            *uscf;
+    ngx_http_upstream_keepalive_srv_conf_t  *kcf;
+
+    ngx_int_t    n;
+    ngx_str_t   *value;
+    ngx_uint_t   i;
+
+    uscf = ngx_http_conf_get_module_srv_conf(cf, ngx_http_upstream_module);
+
+    kcf = ngx_http_conf_upstream_srv_conf(uscf,
+                                          ngx_http_upstream_keepalive_module);
+
+    kcf->original_init_upstream = uscf->peer.init_upstream
+                                  ? uscf->peer.init_upstream
+                                  : ngx_http_upstream_init_round_robin;
+
+    uscf->peer.init_upstream = ngx_http_upstream_init_keepalive;
+
+    /* read options */
+
+    value = cf->args->elts;
+
+    n = ngx_atoi(value[1].data, value[1].len);
+
+    if (n == NGX_ERROR || n == 0) {
+        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                           "invalid value \"%V\" in \"%V\" directive",
+                           &value[1], &cmd->name);
+        return NGX_CONF_ERROR;
+    }
+
+    kcf->max_cached = n;
+
+    for (i = 2; i < cf->args->nelts; i++) {
+
+        if (ngx_strcmp(value[i].data, "single") == 0) {
+            kcf->single = 1;
+            continue;
+        }
+
+        goto invalid;
+    }
+
+    return NGX_CONF_OK;
+
+invalid:
+
+    ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                       "invalid parameter \"%V\"", &value[i]);
+
+    return NGX_CONF_ERROR;
+}
diff --git a/src/http/modules/perl/nginx.pm b/src/http/modules/perl/nginx.pm
index 6dedc6d7d..429af0d1c 100644
--- a/src/http/modules/perl/nginx.pm
+++ b/src/http/modules/perl/nginx.pm
@@ -48,7 +48,7 @@ our @EXPORT = qw(
     HTTP_INSUFFICIENT_STORAGE
 );
 
-our $VERSION = '1.1.3';
+our $VERSION = '1.1.4';
 
 require XSLoader;
 XSLoader::load('nginx', $VERSION);