Add --use-spdy option to control initial max concurrent streams.

e.g.: out/Debug/chrome --use-spdy=init-max-streams=100

BUG=none
TEST=none


Review URL: http://codereview.chromium.org/8258005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@105266 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 21 insertions, 5 deletions

diff --git a/net/http/http_network_layer.cc b/net/http/http_network_layer.cc
index e8ee62c..759ea13 100644
--- a/net/http/http_network_layer.cc
+++ b/net/http/http_network_layer.cc
@@ -77,6 +77,8 @@ void HttpNetworkLayer::EnableSpdy(const std::string& mode) {
   // No spdy specified.
   static const char kNpnProtosHttpOnly[] = "\x08http/1.1\x07http1.1";
 
+  static const char kInitialMaxConcurrentStreams[] = "init-max-streams";
+
   std::vector<std::string> spdy_options;
   base::SplitString(mode, ',', &spdy_options);
 
@@ -127,6 +129,10 @@ void HttpNetworkLayer::EnableSpdy(const std::string& mode) {
     } else if (option == kSingleDomain) {
       SpdySessionPool::ForceSingleDomain();
       LOG(ERROR) << "FORCING SINGLE DOMAIN";
+    } else if (option == kInitialMaxConcurrentStreams) {
+      int streams;
+      if (base::StringToInt(value, &streams) && streams > 0)
+        SpdySession::set_init_max_concurrent_streams(streams);
     } else if (option.empty() && it == spdy_options.begin()) {
       continue;
     } else {
diff --git a/net/spdy/spdy_session.cc b/net/spdy/spdy_session.cc
index fd19edc..cd7d10b 100644
--- a/net/spdy/spdy_session.cc
+++ b/net/spdy/spdy_session.cc
@@ -208,6 +208,9 @@ bool SpdySession::use_ssl_ = true;
 bool SpdySession::use_flow_control_ = false;
 
 // static
+size_t SpdySession::init_max_concurrent_streams_ = 10;
+
+// static
 size_t SpdySession::max_concurrent_stream_limit_ = 256;
 
 SpdySession::SpdySession(const HostPortProxyPair& host_port_proxy_pair,
@@ -233,7 +236,7 @@ SpdySession::SpdySession(const HostPortProxyPair& host_port_proxy_pair,
       certificate_error_code_(OK),
       error_(OK),
       state_(IDLE),
-      max_concurrent_streams_(kDefaultMaxConcurrentStreams),
+      max_concurrent_streams_(init_max_concurrent_streams_),
       streams_initiated_count_(0),
       streams_pushed_count_(0),
       streams_pushed_and_claimed_count_(0),
diff --git a/net/spdy/spdy_session.h b/net/spdy/spdy_session.h
index c3711a1..96b67f9 100644
--- a/net/spdy/spdy_session.h
+++ b/net/spdy/spdy_session.h
@@ -147,12 +147,20 @@ class NET_EXPORT SpdySession : public base::RefCounted<SpdySession>,
   static void set_flow_control(bool enable) { use_flow_control_ = enable; }
   static bool flow_control() { return use_flow_control_; }
 
-  // Sets the max concurrent streams per session.
+  // Sets the max concurrent streams per session, as a ceiling on any server
+  // specific SETTINGS value.
   static void set_max_concurrent_streams(size_t value) {
     max_concurrent_stream_limit_ = value;
   }
   static size_t max_concurrent_streams() {
-      return max_concurrent_stream_limit_;
+    return max_concurrent_stream_limit_;
+  }
+
+  // The initial max concurrent streams per session, can be overridden by the
+  // server via SETTINGS.
+  static void set_init_max_concurrent_streams(size_t value) {
+    init_max_concurrent_streams_ =
+        std::min(value, max_concurrent_stream_limit_);
   }
 
   // Send WINDOW_UPDATE frame, called by a stream whenever receive window
@@ -251,8 +259,6 @@ class NET_EXPORT SpdySession : public base::RefCounted<SpdySession>,
     CLOSED
   };
 
-  enum { kDefaultMaxConcurrentStreams = 10 };
-
   virtual ~SpdySession();
 
   void ProcessPendingCreateStreams();
@@ -449,6 +455,7 @@ class NET_EXPORT SpdySession : public base::RefCounted<SpdySession>,
 
   static bool use_ssl_;
   static bool use_flow_control_;
+  static size_t init_max_concurrent_streams_;
   static size_t max_concurrent_stream_limit_;
 };