Revert of Per-renderer WebSocket throttling

content/browser/renderer_host/websocket_dispatcher_host.cc

Index: content/browser/renderer_host/websocket_dispatcher_host.cc
diff --git a/content/browser/renderer_host/websocket_dispatcher_host.cc b/content/browser/renderer_host/websocket_dispatcher_host.cc
index ab4e68b76c1c17a6e722d2e38ae2438f14478bb0..9aa7a5e2d3c64f22374cad9430d120d3e44a4aea 100644
--- a/content/browser/renderer_host/websocket_dispatcher_host.cc
+++ b/content/browser/renderer_host/websocket_dispatcher_host.cc
@@ -9,8 +9,6 @@
 
 #include "base/callback.h"
 #include "base/logging.h"
-#include "base/numerics/safe_conversions.h"
-#include "base/rand_util.h"
 #include "base/stl_util.h"
 #include "content/browser/child_process_security_policy_impl.h"
 #include "content/browser/renderer_host/websocket_host.h"
@@ -25,10 +23,6 @@
 // fully-qualified every time.
 typedef WebSocketDispatcherHost::WebSocketHostState WebSocketHostState;
 
-// Max number of pending connections per WebSocketDispatcherHost
-// used for per-renderer WebSocket throttling.
-const int kMaxPendingWebSocketConnections = 255;
-
 }  // namespace
 
 WebSocketDispatcherHost::WebSocketDispatcherHost(
@@ -39,12 +33,7 @@
       get_context_callback_(get_context_callback),
       websocket_host_factory_(
           base::Bind(&WebSocketDispatcherHost::CreateWebSocketHost,
-                     base::Unretained(this))),
-      num_pending_connections_(0),
-      num_current_succeeded_connections_(0),
-      num_previous_succeeded_connections_(0),
-      num_current_failed_connections_(0),
-      num_previous_failed_connections_(0) {}
+                     base::Unretained(this))) {}
 
 WebSocketDispatcherHost::WebSocketDispatcherHost(
     int process_id,
@@ -53,18 +42,10 @@
     : BrowserMessageFilter(WebSocketMsgStart),
       process_id_(process_id),
       get_context_callback_(get_context_callback),
-      websocket_host_factory_(websocket_host_factory),
-      num_pending_connections_(0),
-      num_current_succeeded_connections_(0),
-      num_previous_succeeded_connections_(0),
-      num_current_failed_connections_(0),
-      num_previous_failed_connections_(0) {}
+      websocket_host_factory_(websocket_host_factory) {}
 
-WebSocketHost* WebSocketDispatcherHost::CreateWebSocketHost(
-    int routing_id,
-    base::TimeDelta delay) {
-  return new WebSocketHost(
-      routing_id, this, get_context_callback_.Run(), delay);
+WebSocketHost* WebSocketDispatcherHost::CreateWebSocketHost(int routing_id) {
+  return new WebSocketHost(routing_id, this, get_context_callback_.Run());
 }
 
 bool WebSocketDispatcherHost::OnMessageReceived(const IPC::Message& message) {
@@ -92,24 +73,8 @@
       // little extreme. So for now just ignore the bogus request.
       return true;  // We handled the message (by ignoring it).
     }
-    if (num_pending_connections_ >= kMaxPendingWebSocketConnections) {
-      if(!Send(new WebSocketMsg_NotifyFailure(routing_id,
-          "Error in connection establishment: net::ERR_INSUFFICIENT_RESOURCES"
-          ))) {
-        DVLOG(1) << "Sending of message type "
-                 << "WebSocketMsg_NotifyFailure failed.";
-      }
-      return true;
-    }
-    host = websocket_host_factory_.Run(routing_id, CalculateDelay());
+    host = websocket_host_factory_.Run(routing_id);
     hosts_.insert(WebSocketHostTable::value_type(routing_id, host));
-    ++num_pending_connections_;
-    if (!throttling_period_timer_.IsRunning())
-      throttling_period_timer_.Start(
-          FROM_HERE,
-          base::TimeDelta::FromMinutes(2),
-          this,
-          &WebSocketDispatcherHost::ThrottlingPeriodTimerCallback);
   }
   if (!host) {
     DVLOG(1) << "Received invalid routing ID " << routing_id
@@ -147,14 +112,6 @@
     int routing_id,
     const std::string& selected_protocol,
     const std::string& extensions) {
-  // Update throttling counters (success).
-  WebSocketHost* host = GetHost(routing_id);
-  DCHECK(host);
-  host->OnHandshakeSucceeded();
-  --num_pending_connections_;
-  DCHECK_GE(num_pending_connections_, 0);
-  ++num_current_succeeded_connections_;
-
   return SendOrDrop(new WebSocketMsg_AddChannelResponse(
       routing_id, selected_protocol, extensions));
 }
@@ -235,55 +192,8 @@
 void WebSocketDispatcherHost::DeleteWebSocketHost(int routing_id) {
   WebSocketHostTable::iterator it = hosts_.find(routing_id);
   DCHECK(it != hosts_.end());
-  DCHECK(it->second);
-  if (!it->second->handshake_succeeded()) {
-    // Update throttling counters (failure).
-    --num_pending_connections_;
-    DCHECK_GE(num_pending_connections_, 0);
-    ++num_current_failed_connections_;
-  }
-
   delete it->second;
   hosts_.erase(it);
-
-  DCHECK_LE(base::checked_cast<size_t>(num_pending_connections_),
-            hosts_.size());
-}
-
-int64_t WebSocketDispatcherHost::num_failed_connections() const {
-  return num_previous_failed_connections_ +
-         num_current_failed_connections_;
-}
-
-int64_t WebSocketDispatcherHost::num_succeeded_connections() const {
-  return num_previous_succeeded_connections_ +
-         num_current_succeeded_connections_;
-}
-
-// Calculate delay as described in
-// the per-renderer WebSocket throttling design doc:
-// https://docs.google.com/document/d/1aw2oN5PKfk-1gLnBrlv1OwLA8K3-ykM2ckwX2lubTg4/edit?usp=sharing
-base::TimeDelta WebSocketDispatcherHost::CalculateDelay() const {
-  int64_t f = num_failed_connections();
-  int64_t s = num_succeeded_connections();
-  int p = num_pending_connections();
-  return base::TimeDelta::FromMilliseconds(
-      base::RandInt(1000, 5000) *
-      (1 << std::min(p + f / (s + 1), INT64_C(16))) / 65536);
-}
-
-void WebSocketDispatcherHost::ThrottlingPeriodTimerCallback() {
-  num_previous_failed_connections_ = num_current_failed_connections_;
-  num_current_failed_connections_ = 0;
-
-  num_previous_succeeded_connections_ = num_current_succeeded_connections_;
-  num_current_succeeded_connections_ = 0;
-
-  if (num_pending_connections_ == 0 &&
-      num_previous_failed_connections_ == 0 &&
-      num_previous_succeeded_connections_ == 0) {
-    throttling_period_timer_.Stop();
-  }
 }
 
 }  // namespace content