nghttpx: Deprecate --http2-max-concurrent-streams option

We added 2 new option instead: --frontend-http2-max-concurrent-streams
and --backend-http2-max-concurrent-streams.

gennghttpxfun.py

@@ -122,7 +122,9 @@ OPTIONS = [
     "tls-ticket-key-memcached-cert-file",
     "tls-ticket-key-memcached-private-key-file",
     "tls-ticket-key-memcached-address-family",
-    "backend-address-family"
+    "backend-address-family",
+    "frontend-http2-max-concurrent-streams",
+    "backend-http2-max-concurrent-streams"
 ]
 
 LOGVARS = [

src/shrpx.cc

@@ -1096,6 +1096,7 @@ void fill_default_config() {
     // HTTP/2 SPDY/3.1 has connection-level flow control. The default
     // window size for HTTP/2 is 64KiB - 1. SPDY/3's default is 64KiB
     upstreamconf.connection_window_bits = 16;
+    upstreamconf.max_concurrent_streams = 100;
 
     nghttp2_option_new(&upstreamconf.option);
     nghttp2_option_set_no_auto_window_update(upstreamconf.option, 1);
@@ -1106,14 +1107,13 @@ void fill_default_config() {
     auto &downstreamconf = http2conf.downstream;
     downstreamconf.window_bits = 16;
     downstreamconf.connection_window_bits = 16;
+    downstreamconf.max_concurrent_streams = 100;
 
     nghttp2_option_new(&downstreamconf.option);
     nghttp2_option_set_no_auto_window_update(downstreamconf.option, 1);
     nghttp2_option_set_peer_max_concurrent_streams(downstreamconf.option, 100);
   }
 
-  http2conf.max_concurrent_streams = 100;
-
   auto &loggingconf = mod_config()->logging;
   {
     auto &accessconf = loggingconf.access;
@@ -1621,10 +1621,18 @@ SSL/TLS:
               the complete HTTP/2 cipher suites black list.
 
 HTTP/2 and SPDY:
-  -c, --http2-max-concurrent-streams=<N>
+  -c, --frontend-http2-max-concurrent-streams=<N>
               Set the maximum number of  the concurrent streams in one
-              HTTP/2 and SPDY session.
+              frontend HTTP/2 and SPDY session.
-              Default: )" << get_config()->http2.max_concurrent_streams << R"(
+              Default:  )"
+      << get_config()->http2.upstream.max_concurrent_streams << R"(
+  --backend-http2-max-concurrent-streams=<N>
+              Set the maximum number of  the concurrent streams in one
+              backend  HTTP/2 session.   This sets  maximum number  of
+              concurrent opened pushed streams.  The maximum number of
+              concurrent requests are set by a remote server.
+              Default: )"
+      << get_config()->http2.downstream.max_concurrent_streams << R"(
   --frontend-http2-window-bits=<N>
               Sets the  per-stream initial window size  of HTTP/2 SPDY
               frontend connection.  For HTTP/2,  the size is 2**<N>-1.
@@ -2451,6 +2459,10 @@ int main(int argc, char **argv) {
         {SHRPX_OPT_TLS_SESSION_CACHE_MEMCACHED_ADDRESS_FAMILY,
          required_argument, &flag, 115},
         {SHRPX_OPT_BACKEND_ADDRESS_FAMILY, required_argument, &flag, 116},
+        {SHRPX_OPT_FRONTEND_HTTP2_MAX_CONCURRENT_STREAMS, required_argument,
+         &flag, 117},
+        {SHRPX_OPT_BACKEND_HTTP2_MAX_CONCURRENT_STREAMS, required_argument,
+         &flag, 118},
         {nullptr, 0, nullptr, 0}};
 
     int option_index = 0;
@@ -2946,6 +2958,16 @@ int main(int argc, char **argv) {
         // --backend-address-family
         cmdcfgs.emplace_back(SHRPX_OPT_BACKEND_ADDRESS_FAMILY, optarg);
         break;
+      case 117:
+        // --frontend-http2-max-concurrent-streams
+        cmdcfgs.emplace_back(SHRPX_OPT_FRONTEND_HTTP2_MAX_CONCURRENT_STREAMS,
+                             optarg);
+        break;
+      case 118:
+        // --backend-http2-max-concurrent-streams
+        cmdcfgs.emplace_back(SHRPX_OPT_BACKEND_HTTP2_MAX_CONCURRENT_STREAMS,
+                             optarg);
+        break;
       default:
         break;
       }

src/shrpx_config.cc

@@ -660,6 +660,7 @@ enum {
   SHRPX_OPTID_BACKEND_HTTP1_TLS,
   SHRPX_OPTID_BACKEND_HTTP2_CONNECTION_WINDOW_BITS,
   SHRPX_OPTID_BACKEND_HTTP2_CONNECTIONS_PER_WORKER,
+  SHRPX_OPTID_BACKEND_HTTP2_MAX_CONCURRENT_STREAMS,
   SHRPX_OPTID_BACKEND_HTTP2_WINDOW_BITS,
   SHRPX_OPTID_BACKEND_IPV4,
   SHRPX_OPTID_BACKEND_IPV6,
@@ -692,6 +693,7 @@ enum {
   SHRPX_OPTID_FRONTEND_HTTP2_CONNECTION_WINDOW_BITS,
   SHRPX_OPTID_FRONTEND_HTTP2_DUMP_REQUEST_HEADER,
   SHRPX_OPTID_FRONTEND_HTTP2_DUMP_RESPONSE_HEADER,
+  SHRPX_OPTID_FRONTEND_HTTP2_MAX_CONCURRENT_STREAMS,
   SHRPX_OPTID_FRONTEND_HTTP2_READ_TIMEOUT,
   SHRPX_OPTID_FRONTEND_HTTP2_WINDOW_BITS,
   SHRPX_OPTID_FRONTEND_NO_TLS,
@@ -1398,6 +1400,9 @@ int option_lookup_token(const char *name, size_t namelen) {
       if (util::strieq_l("backend-http2-connection-window-bit", name, 35)) {
         return SHRPX_OPTID_BACKEND_HTTP2_CONNECTION_WINDOW_BITS;
       }
+      if (util::strieq_l("backend-http2-max-concurrent-stream", name, 35)) {
+        return SHRPX_OPTID_BACKEND_HTTP2_MAX_CONCURRENT_STREAMS;
+      }
       break;
     }
     break;
@@ -1412,6 +1417,9 @@ int option_lookup_token(const char *name, size_t namelen) {
       if (util::strieq_l("frontend-http2-connection-window-bit", name, 36)) {
         return SHRPX_OPTID_FRONTEND_HTTP2_CONNECTION_WINDOW_BITS;
       }
+      if (util::strieq_l("frontend-http2-max-concurrent-stream", name, 36)) {
+        return SHRPX_OPTID_FRONTEND_HTTP2_MAX_CONCURRENT_STREAMS;
+      }
       break;
     }
     break;
@@ -1559,8 +1567,20 @@ int parse_config(const char *opt, const char *optarg,
 #else // !NOTHREADS
     return parse_uint(&mod_config()->num_worker, opt, optarg);
 #endif // !NOTHREADS
-  case SHRPX_OPTID_HTTP2_MAX_CONCURRENT_STREAMS:
+  case SHRPX_OPTID_HTTP2_MAX_CONCURRENT_STREAMS: {
-    return parse_uint(&mod_config()->http2.max_concurrent_streams, opt, optarg);
+    LOG(WARN) << opt << ": deprecated. Use "
+              << SHRPX_OPT_FRONTEND_HTTP2_MAX_CONCURRENT_STREAMS << " and "
+              << SHRPX_OPT_BACKEND_HTTP2_MAX_CONCURRENT_STREAMS << " instead.";
+    size_t n;
+    if (parse_uint(&n, opt, optarg) != 0) {
+      return -1;
+    }
+    auto &http2conf = mod_config()->http2;
+    http2conf.upstream.max_concurrent_streams = n;
+    http2conf.downstream.max_concurrent_streams = n;
+
+    return 0;
+  }
   case SHRPX_OPTID_LOG_LEVEL:
     if (Log::set_severity_level_by_name(optarg) == -1) {
       LOG(ERROR) << opt << ": Invalid severity level: " << optarg;
@@ -2314,6 +2334,12 @@ int parse_config(const char *opt, const char *optarg,
   case SHRPX_OPTID_BACKEND_ADDRESS_FAMILY:
     return parse_address_family(&mod_config()->conn.downstream.family, opt,
                                 optarg);
+  case SHRPX_OPTID_FRONTEND_HTTP2_MAX_CONCURRENT_STREAMS:
+    return parse_uint(&mod_config()->http2.upstream.max_concurrent_streams, opt,
+                      optarg);
+  case SHRPX_OPTID_BACKEND_HTTP2_MAX_CONCURRENT_STREAMS:
+    return parse_uint(&mod_config()->http2.downstream.max_concurrent_streams,
+                      opt, optarg);
   case SHRPX_OPTID_CONF:
     LOG(WARN) << "conf: ignored";
 

src/shrpx_config.h

@@ -228,6 +228,10 @@ constexpr char SHRPX_OPT_TLS_TICKET_KEY_MEMCACHED_PRIVATE_KEY_FILE[] =
 constexpr char SHRPX_OPT_TLS_TICKET_KEY_MEMCACHED_ADDRESS_FAMILY[] =
     "tls-ticket-key-memcached-address-family";
 constexpr char SHRPX_OPT_BACKEND_ADDRESS_FAMILY[] = "backend-address-family";
+constexpr char SHRPX_OPT_FRONTEND_HTTP2_MAX_CONCURRENT_STREAMS[] =
+    "frontend-http2-max-concurrent-streams";
+constexpr char SHRPX_OPT_BACKEND_HTTP2_MAX_CONCURRENT_STREAMS[] =
+    "backend-http2-max-concurrent-streams";
 
 constexpr size_t SHRPX_OBFUSCATED_NODE_LENGTH = 8;
 
@@ -479,18 +483,19 @@ struct Http2Config {
     nghttp2_session_callbacks *callbacks;
     size_t window_bits;
     size_t connection_window_bits;
+    size_t max_concurrent_streams;
   } upstream;
   struct {
     nghttp2_option *option;
     nghttp2_session_callbacks *callbacks;
     size_t window_bits;
     size_t connection_window_bits;
+    size_t max_concurrent_streams;
   } downstream;
   struct {
     ev_tstamp stream_read;
     ev_tstamp stream_write;
   } timeout;
-  size_t max_concurrent_streams;
   bool no_cookie_crumbling;
   bool no_server_push;
 };

src/shrpx_http2_session.cc

@@ -1453,7 +1453,7 @@ int Http2Session::connection_made() {
   std::array<nghttp2_settings_entry, 3> entry;
   size_t nentry = 2;
   entry[0].settings_id = NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS;
-  entry[0].value = http2conf.max_concurrent_streams;
+  entry[0].value = http2conf.downstream.max_concurrent_streams;
 
   entry[1].settings_id = NGHTTP2_SETTINGS_INITIAL_WINDOW_SIZE;
   entry[1].value = (1 << http2conf.downstream.window_bits) - 1;

src/shrpx_http2_upstream.cc

@@ -846,7 +846,7 @@ Http2Upstream::Http2Upstream(ClientHandler *handler)
   // TODO Maybe call from outside?
   std::array<nghttp2_settings_entry, 2> entry;
   entry[0].settings_id = NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS;
-  entry[0].value = http2conf.max_concurrent_streams;
+  entry[0].value = http2conf.upstream.max_concurrent_streams;
 
   entry[1].settings_id = NGHTTP2_SETTINGS_INITIAL_WINDOW_SIZE;
   entry[1].value = (1 << http2conf.upstream.window_bits) - 1;

src/shrpx_spdy_upstream.cc

@@ -547,7 +547,7 @@ SpdyUpstream::SpdyUpstream(uint16_t version, ClientHandler *handler)
   // TODO Maybe call from outside?
   std::array<spdylay_settings_entry, 2> entry;
   entry[0].settings_id = SPDYLAY_SETTINGS_MAX_CONCURRENT_STREAMS;
-  entry[0].value = http2conf.max_concurrent_streams;
+  entry[0].value = http2conf.upstream.max_concurrent_streams;
   entry[0].flags = SPDYLAY_ID_FLAG_SETTINGS_NONE;
 
   entry[1].settings_id = SPDYLAY_SETTINGS_INITIAL_WINDOW_SIZE;