diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 9423c46547a876bd4df47710d515bb6f9bb89528..03d2e276a825e33e9cc348b64f74afcf419731de 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -13,7 +13,7 @@ In order to protect both you and ourselves, you will need to sign the
 ### Technical requirements
 
 You will need several tools to work with this repository. In addition to all of
-the packages described in the [INSTALL](INSTALL) file, you will also need
+the packages described in the [INSTALL](INSTALL.md) file, you will also need
 python, and the mako template renderer. To install the latter, using pip, one
 should simply be able to do `pip install mako`.
 
diff --git a/INSTALL b/INSTALL
deleted file mode 100644
index e33f8970a951afc95766e1bc08cb20b2915df77c..0000000000000000000000000000000000000000
--- a/INSTALL
+++ /dev/null
@@ -1,217 +0,0 @@
-These instructions only cover building grpc C and C++ libraries under
-typical unix systems. If you need more information, please try grpc's
-wiki pages:
-
-  https://github.com/google/grpc/wiki
-
-
-*************************
-* If you are in a hurry *
-*************************
-
-On Linux (Debian):
-
- Note: you will need to add the Debian 'jessie-backports' distribution to your sources
- file first.
-
- Add the following line to your `/etc/apt/sources.list` file:
-
-   deb http://http.debian.net/debian jessie-backports main
-
- Install the gRPC library:
-
- $ [sudo] apt-get install libgrpc-dev
-
-OR
-
- $ git clone https://github.com/grpc/grpc.git
- $ cd grpc
- $ git submodule update --init
- $ make 
- $ [sudo] make install
-
-You don't need anything else than GNU Make, gcc and autotools. Under a Debian
-or Ubuntu system, this should boil down to the following packages:
-
- $ [sudo] apt-get install build-essential autoconf libtool
-
-Building the python wrapper requires the following:
-
- $ [sudo] apt-get install python-all-dev python-virtualenv
-
-If you want to install in a different directory than the default /usr/lib, you can
-override it on the command line:
-
- $ [sudo] make install prefix=/opt
-
-
-*******************************
-* More detailled instructions *
-*******************************
-
-Setting up dependencies
-=======================
-
-Dependencies to compile the libraries
--------------------------------------
-
-grpc libraries have few external dependencies. If you need to compile and
-install them, they are present in the third_party directory if you have
-cloned the github repository recursively. If you didn't clone recursively,
-you can still get them later by running the following command:
-
-  $ git submodule update --init
-
-Note that the Makefile makes it much easier for you to compile from sources
-if you were to clone recursively our git repository: it will automatically
-compile zlib and OpenSSL, which are core requirements for grpc. Note this
-creates grpc libraries that will have zlib and OpenSSL built-in inside of them,
-which significantly increases the libraries' size.
-
-In order to decrease that size, you can manually install zlib and OpenSSL on
-your system, so that the Makefile can use them instead.
-
-Under a Debian or Ubuntu system, one can acquire the development package
-for zlib this way:
-
-  # apt-get install zlib1g-dev
-
-To the best of our knowledge, no distribution has an OpenSSL package that
-supports ALPN yet, so you would still have to depend on installing from source
-for that particular dependency if you want to reduce the libraries' size.
-
-The recommended version of OpenSSL that provides ALPN support is available
-at this URL:
-
-  https://www.openssl.org/source/openssl-1.0.2.tar.gz
-
-
-Dependencies to compile and run the tests
------------------------------------------
-
-Compiling and running grpc plain-C tests dont't require any more dependency.
-
-
-Compiling and running grpc C++ tests depend on protobuf 3.0.0, gtest and
-gflags. Although gflags is provided in third_party, you will need to manually
-install that dependency on your system to run these tests.
-
-Under a Debian or Ubuntu system, you can install the gtests and gflags packages
-using apt-get:
-
-  # apt-get install libgflags-dev libgtest-dev
-
-However, protobuf 3.0.0 isn't in a debian package yet, but the Makefile will
-automatically try and compile the one present in third_party if you cloned the
-repository recursively, and that it detects your system is lacking it.
-
-Compiling and installing protobuf 3.0.0 requires a few more dependencies in
-itself, notably the autoconf suite. If you have apt-get, you can install
-these dependencies this way:
-
-  # apt-get install autoconf libtool
-
-If you want to run the tests using one of the sanitized configurations, you
-will need clang and its instrumented libc++:
-
-  # apt-get install clang libc++-dev
-
-Mac-specific notes:
--------------------
-
-For a Mac system, git is not available by default. You will first need to
-install Xcode from the Mac AppStore and then run the following command from a
-terminal:
-
-  $ sudo xcode-select --install
-
-You should also install "port" following the instructions at
-https://www.macports.org . This will reside in /opt/local/bin/port for
-most Mac installations. Do the "git submodule" command listed above.
-
-Then execute the following for all the needed build dependencies
-
-  $ sudo /opt/local/bin/port install autoconf automake libtool gflags cmake
-  $ mkdir ~/gtest-svn
-  $ svn checkout http://googletest.googlecode.com/svn/trunk/ gtest-svn
-  $ mkdir mybuild
-  $ cd mybuild
-  $ cmake ../gtest-svn
-  $ make
-  $ make gtest.a gtest_main.a
-  $ sudo cp libgtest.a libgtest_main.a /opt/local/lib
-  $ sudo mkdir /opt/local/include/gtest
-  $ sudo cp -pr ../gtest-svn/include/gtest /opt/local/include/gtest
-
-If you are going to make changes and need to regenerate the projects file,
-you will need to install certain modules for python.
-
-  $ sudo easy_install simplejson mako
-
-Mingw-specific notes:
----------------------
-
-While gRPC compiles properly under mingw, some more preparation work is needed.
-The recommendation is to use msys2. The installation instructions are available
-at that address: http://msys2.github.io/
-
-Once this is installed, make sure you are using the following: MinGW-w64 Win64.
-You'll be required to install a few more packages:
-
-  $ pacman -S make mingw-w64-x86_64-gcc mingw-w64-x86_64-zlib autoconf automake libtool
-
-Please also install OpenSSL from that website:
-
-  http://slproweb.com/products/Win32OpenSSL.html
-
-The package Win64 OpenSSL v1.0.2a should do. At that point you should be able
-to compile gRPC with the following:
-
-  $ export LDFLAGS="-L/mingw64/lib -L/c/OpenSSL-Win64"
-  $ export CPPFLAGS="-I/mingw64/include -I/c/OpenSSL-Win64/include"
-  $ make
-
-A word on OpenSSL
------------------
-
-Secure HTTP2 requires the TLS extension ALPN (see rfc 7301 and
-http://http2.github.io/http2-spec/ section 3.3). Our HTTP2 implementation
-relies on OpenSSL's implementation. OpenSSL 1.0.2 is the first released version
-of OpenSSL that has ALPN support, and this explains our dependency on it.
-
-Note that the Makefile supports compiling only the unsecure elements of grpc,
-and if you do not have OpenSSL and do not want it, you can still proceed
-with installing only the elements you require. However, we strongly recommend
-the use of encryption for all network traffic, and discourage the use of grpc
-without TLS.
-
-
-Compiling
-=========
-
-If you have all the dependencies mentioned above, you should simply be able
-to go ahead and run "make" to compile grpc's C and C++ libraries:
-
-  $ make
-
-
-Testing
-=======
-
-To build and run the tests, you can run the command:
-
-  $ make test
-
-If you want to be able to run them in parallel, and get better output, you can
-also use the python tool we have written:
-
-  $ ./tools/run_tests/run_tests.py
-
-
-Installing
-==========
-
-Once everything is compiled, you should be able to install grpc C and C++
-libraries and headers:
-
-  # make install
diff --git a/INSTALL.md b/INSTALL.md
new file mode 100644
index 0000000000000000000000000000000000000000..d9411db021d5784771951d06fdd13070b7fcf449
--- /dev/null
+++ b/INSTALL.md
@@ -0,0 +1,46 @@
+#If you are in a hurry
+
+For language-specific installation instructions for gRPC runtime, please
+refer to these documents
+
+ * [C++](examples/cpp)
+ * [C#](src/csharp): NuGet package `Grpc`
+ * [Go](https://github.com/grpc/grpc-go): `go get google.golang.org/grpc`
+ * [Java](https://github.com/grpc/grpc-java)
+ * [Node](src/node): `npm install grpc`
+ * [Objective-C](src/objective-c)
+ * [PHP](src/php): `pecl install grpc-beta`
+ * [Python](src/python/grpcio): `pip install grpcio`
+ * [Ruby](src/ruby): `gem install grpc`
+
+
+#Pre-requisites
+
+##Linux
+
+```sh
+ $ [sudo] apt-get install build-essential autoconf libtool
+```
+
+##Mac OSX
+
+For a Mac system, git is not available by default. You will first need to
+install Xcode from the Mac AppStore and then run the following command from a
+terminal:
+
+```sh
+ $ [sudo] xcode-select --install
+```
+
+#Build from Source
+
+For developers who are interested to contribute, here is how to compile the
+gRPC C Core library.
+
+```sh
+ $ git clone https://github.com/grpc/grpc.git
+ $ cd grpc
+ $ git submodule update --init
+ $ make 
+ $ [sudo] make install
+```
diff --git a/README.md b/README.md
index 033e09b91b7e8ee9bbcfc336688479d68840c936..abb4905392cdc96f0b41e88e74308c5189d0be3b 100644
--- a/README.md
+++ b/README.md
@@ -13,7 +13,7 @@ You can find more detailed documentation and examples in the [doc](doc) and [exa
 
 #Installation
 
-See [grpc/INSTALL](INSTALL) for installation instructions for various platforms.
+See [INSTALL](INSTALL.md) for installation instructions for various platforms.
 
 #Repository Structure & Status
 
diff --git a/doc/interop-test-descriptions.md b/doc/interop-test-descriptions.md
index e618e967ee059c9aa88ad0f2d126354cc8d2a2e7..3beb1d11f4a8f2a28164376dadc704ada27f3030 100644
--- a/doc/interop-test-descriptions.md
+++ b/doc/interop-test-descriptions.md
@@ -2,9 +2,8 @@ Interoperability Test Case Descriptions
 =======================================
 
 Client and server use
-[test.proto](https://github.com/grpc/grpc/blob/master/test/proto/test.proto)
-and the [gRPC over HTTP/2 v2
-protocol](https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md).
+[test.proto](../src/proto/grpc/testing/test.proto)
+and the [gRPC over HTTP/2 v2 protocol](./PROTOCOL-HTTP2.md).
 
 Client
 ------
diff --git a/examples/README.md b/examples/README.md
index 84ec80057e1620eb295503aba2977c5ec073b26b..cd85417ca202d41c47e155a539d9284185363b0e 100644
--- a/examples/README.md
+++ b/examples/README.md
@@ -447,4 +447,4 @@ $ greeter_client
 ## Read more!
 
 - You can find links to language-specific tutorials, examples, and other docs in each language's [quick start](#quickstart).
-- [gRPC Authentication Support](doc/grpc-auth-support.md) introduces authentication support in gRPC with supported mechanisms and examples.
+- [gRPC Authentication Support](http://www.grpc.io/docs/guides/auth.html) introduces authentication support in gRPC with supported mechanisms and examples.
diff --git a/examples/cpp/README.md b/examples/cpp/README.md
index 85c495099b79b072198a69d5b7965ee632136828..979ba55dbb5d1e51f698111e3f3a649f1398cb61 100644
--- a/examples/cpp/README.md
+++ b/examples/cpp/README.md
@@ -2,7 +2,7 @@
 
 ## Installation
 
-To install gRPC on your system, follow the instructions [here](../../INSTALL).
+To install gRPC on your system, follow the instructions [here](../../INSTALL.md).
 
 ## Hello C++ gRPC!
 
diff --git a/examples/cpp/cpptutorial.md b/examples/cpp/cpptutorial.md
index cd1cddb11157be6f1bd48d07955a15f5bd4898a0..ef9ca99c0fef6ccec3a399e930f5186e0a1e2518 100644
--- a/examples/cpp/cpptutorial.md
+++ b/examples/cpp/cpptutorial.md
@@ -91,7 +91,7 @@ message Point {
 
 Next we need to generate the gRPC client and server interfaces from our .proto service definition. We do this using the protocol buffer compiler `protoc` with a special gRPC C++ plugin.
 
-For simplicity, we've provided a [makefile](route_guide/Makefile) that runs `protoc` for you with the appropriate plugin, input, and output (if you want to run this yourself, make sure you've installed protoc and followed the gRPC code [installation instructions](../../INSTALL) first):
+For simplicity, we've provided a [makefile](route_guide/Makefile) that runs `protoc` for you with the appropriate plugin, input, and output (if you want to run this yourself, make sure you've installed protoc and followed the gRPC code [installation instructions](../../INSTALL.md) first):
 
 ```shell
 $ make route_guide.grpc.pb.cc route_guide.pb.cc
diff --git a/examples/cpp/helloworld/README.md b/examples/cpp/helloworld/README.md
index 90f3d6b14755c897479edc0bee094e038f0e4f4d..8e11f7cdf3ee893858d261c75c4586aa13b16b1c 100644
--- a/examples/cpp/helloworld/README.md
+++ b/examples/cpp/helloworld/README.md
@@ -2,7 +2,7 @@
 
 ### Install gRPC
 Make sure you have installed gRPC on your system. Follow the instructions here:
-[https://github.com/grpc/grpc/blob/master/INSTALL](../../../INSTALL).
+[https://github.com/grpc/grpc/blob/master/INSTALL](../../../INSTALL.md).
 
 ### Get the tutorial source code
 
diff --git a/examples/node/README.md b/examples/node/README.md
index 7a2bc9794f3a0e6458599d0c067fe538f603fd45..c1ef6b05ab0bd484c3f8b9f42098bf9f4796e163 100644
--- a/examples/node/README.md
+++ b/examples/node/README.md
@@ -20,7 +20,7 @@ TRY IT!
  - Run the server
 
    ```sh
-   $ # from this directory (grpc_common/node).
+   $ # from this directory
    $ node ./greeter_server.js &
    ```
 
diff --git a/grpc.def b/grpc.def
index bd0bc85a7c3bcfa21d3013a0d7c347675c9df009..f81aa1b05a6e84ee70aece13dd979058c8128638 100644
--- a/grpc.def
+++ b/grpc.def
@@ -182,6 +182,7 @@ EXPORTS
     gpr_event_wait
     gpr_ref_init
     gpr_ref
+    gpr_ref_non_zero
     gpr_refn
     gpr_unref
     gpr_stats_init
diff --git a/include/grpc/impl/codegen/sync.h b/include/grpc/impl/codegen/sync.h
index d2f19d37d66ebcc1ac706b499d38c76c54700421..6fd7d64b299ba46ded0f0ca9d35a817a038050ff 100644
--- a/include/grpc/impl/codegen/sync.h
+++ b/include/grpc/impl/codegen/sync.h
@@ -182,6 +182,10 @@ GPRAPI void gpr_ref_init(gpr_refcount *r, int n);
 /* Increment the reference count *r.  Requires *r initialized. */
 GPRAPI void gpr_ref(gpr_refcount *r);
 
+/* Increment the reference count *r.  Requires *r initialized.
+   Crashes if refcount is zero */
+GPRAPI void gpr_ref_non_zero(gpr_refcount *r);
+
 /* Increment the reference count *r by n.  Requires *r initialized, n > 0. */
 GPRAPI void gpr_refn(gpr_refcount *r, int n);
 
diff --git a/src/core/channel/client_channel.c b/src/core/channel/client_channel.c
index eeac3c146c30cf4b7c3abe1d3487d992ebb1968f..d4ba9508185284e912a5e49cd0ac6adbe6f16f22 100644
--- a/src/core/channel/client_channel.c
+++ b/src/core/channel/client_channel.c
@@ -251,7 +251,7 @@ static void cc_start_transport_op(grpc_exec_ctx *exec_ctx,
 
   grpc_exec_ctx_enqueue(exec_ctx, op->on_consumed, true, NULL);
 
-  GPR_ASSERT(op->set_accept_stream == NULL);
+  GPR_ASSERT(op->set_accept_stream == false);
   if (op->bind_pollset != NULL) {
     grpc_pollset_set_add_pollset(exec_ctx, chand->interested_parties,
                                  op->bind_pollset);
diff --git a/src/core/channel/client_uchannel.c b/src/core/channel/client_uchannel.c
index b1e7155773fd68eda130e652cdadb87fba45e85d..83fcc3a87f52f644f81b6a801edf9eb3b7522fc9 100644
--- a/src/core/channel/client_uchannel.c
+++ b/src/core/channel/client_uchannel.c
@@ -107,7 +107,7 @@ static void cuc_start_transport_op(grpc_exec_ctx *exec_ctx,
 
   grpc_exec_ctx_enqueue(exec_ctx, op->on_consumed, true, NULL);
 
-  GPR_ASSERT(op->set_accept_stream == NULL);
+  GPR_ASSERT(op->set_accept_stream == false);
   GPR_ASSERT(op->bind_pollset == NULL);
 
   if (op->on_connectivity_state_change != NULL) {
diff --git a/src/core/iomgr/iomgr.c b/src/core/iomgr/iomgr.c
index 04580150f3a7117cf78c31fb873f5f5962cfa21f..9c89c2c08a459eb51df983210db8d489cbddb17e 100644
--- a/src/core/iomgr/iomgr.c
+++ b/src/core/iomgr/iomgr.c
@@ -41,9 +41,11 @@
 #include <grpc/support/string_util.h>
 #include <grpc/support/sync.h>
 #include <grpc/support/thd.h>
+#include <grpc/support/useful.h>
 
 #include "src/core/iomgr/iomgr_internal.h"
 #include "src/core/iomgr/timer.h"
+#include "src/core/support/env.h"
 #include "src/core/support/string.h"
 
 static gpr_mu g_mu;
@@ -116,6 +118,9 @@ void grpc_iomgr_shutdown(void) {
                     "memory leaks are likely",
                     count_objects());
             dump_objects("LEAKED");
+            if (grpc_iomgr_abort_on_leaks()) {
+              abort();
+            }
           }
           break;
         }
@@ -154,3 +159,14 @@ void grpc_iomgr_unregister_object(grpc_iomgr_object *obj) {
   gpr_mu_unlock(&g_mu);
   gpr_free(obj->name);
 }
+
+bool grpc_iomgr_abort_on_leaks(void) {
+  char *env = gpr_getenv("GRPC_ABORT_ON_LEAKS");
+  if (env == NULL) return false;
+  static const char *truthy[] = {"yes",  "Yes",  "YES", "true",
+                                 "True", "TRUE", "1"};
+  for (size_t i = 0; i < GPR_ARRAY_SIZE(truthy); i++) {
+    if (0 == strcmp(env, truthy[i])) return true;
+  }
+  return false;
+}
diff --git a/src/core/iomgr/iomgr_internal.h b/src/core/iomgr/iomgr_internal.h
index e372c18e8a070cbba634bcea67ea7d80110b461c..ac2c46ebe6230df3242f4a8a3cb04ba7b3cf7dbf 100644
--- a/src/core/iomgr/iomgr_internal.h
+++ b/src/core/iomgr/iomgr_internal.h
@@ -1,6 +1,6 @@
 /*
  *
- * Copyright 2015, Google Inc.
+ * Copyright 2015-2016, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -34,6 +34,8 @@
 #ifndef GRPC_INTERNAL_CORE_IOMGR_IOMGR_INTERNAL_H
 #define GRPC_INTERNAL_CORE_IOMGR_IOMGR_INTERNAL_H
 
+#include <stdbool.h>
+
 #include "src/core/iomgr/iomgr.h"
 #include <grpc/support/sync.h>
 
@@ -55,4 +57,6 @@ void grpc_iomgr_platform_flush(void);
 /** tear down all platform specific global iomgr structures */
 void grpc_iomgr_platform_shutdown(void);
 
+bool grpc_iomgr_abort_on_leaks(void);
+
 #endif /* GRPC_INTERNAL_CORE_IOMGR_IOMGR_INTERNAL_H */
diff --git a/src/core/support/sync.c b/src/core/support/sync.c
index d368422d9eaf693da5f96494e3c134ffbc030a7e..69e3e39c5cef80d05ba9b2b6553c20bdfe75b271 100644
--- a/src/core/support/sync.c
+++ b/src/core/support/sync.c
@@ -1,6 +1,6 @@
 /*
  *
- * Copyright 2015, Google Inc.
+ * Copyright 2015-2016, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -98,6 +98,11 @@ void gpr_ref_init(gpr_refcount *r, int n) { gpr_atm_rel_store(&r->count, n); }
 
 void gpr_ref(gpr_refcount *r) { gpr_atm_no_barrier_fetch_add(&r->count, 1); }
 
+void gpr_ref_non_zero(gpr_refcount *r) {
+  gpr_atm prior = gpr_atm_no_barrier_fetch_add(&r->count, 1);
+  GPR_ASSERT(prior > 0);
+}
+
 void gpr_refn(gpr_refcount *r, int n) {
   gpr_atm_no_barrier_fetch_add(&r->count, n);
 }
diff --git a/src/core/surface/server.c b/src/core/surface/server.c
index fb5e0d4b9e70a471d9b2bfc4db2793476d2adc64..5b13d4ba526dc84fd070097704c9bbaef7ec9bbb 100644
--- a/src/core/surface/server.c
+++ b/src/core/surface/server.c
@@ -407,8 +407,15 @@ static void destroy_channel(grpc_exec_ctx *exec_ctx, channel_data *chand) {
   maybe_finish_shutdown(exec_ctx, chand->server);
   chand->finish_destroy_channel_closure.cb = finish_destroy_channel;
   chand->finish_destroy_channel_closure.cb_arg = chand;
-  grpc_exec_ctx_enqueue(exec_ctx, &chand->finish_destroy_channel_closure, true,
-                        NULL);
+
+  grpc_transport_op op;
+  memset(&op, 0, sizeof(op));
+  op.set_accept_stream = true;
+  op.on_consumed = &chand->finish_destroy_channel_closure;
+  grpc_channel_next_op(exec_ctx,
+                       grpc_channel_stack_element(
+                           grpc_channel_get_channel_stack(chand->channel), 0),
+                       &op);
 }
 
 static void finish_start_new_rpc(grpc_exec_ctx *exec_ctx, grpc_server *server,
@@ -971,7 +978,8 @@ void grpc_server_setup_transport(grpc_exec_ctx *exec_ctx, grpc_server *s,
 
   GRPC_CHANNEL_INTERNAL_REF(channel, "connectivity");
   memset(&op, 0, sizeof(op));
-  op.set_accept_stream = accept_stream;
+  op.set_accept_stream = true;
+  op.set_accept_stream_fn = accept_stream;
   op.set_accept_stream_user_data = chand;
   op.on_connectivity_state_change = &chand->channel_connectivity_changed;
   op.connectivity_state = &chand->connectivity_state;
diff --git a/src/core/transport/chttp2/internal.h b/src/core/transport/chttp2/internal.h
index d76d31be23f2f4f31c8aec172b580a8a8741d8fe..b720d1ab3e5a64cdb369ac83fcc375f9bff56c4d 100644
--- a/src/core/transport/chttp2/internal.h
+++ b/src/core/transport/chttp2/internal.h
@@ -358,6 +358,9 @@ struct grpc_chttp2_transport {
     /** connectivity tracking */
     grpc_connectivity_state_tracker state_tracker;
   } channel_callback;
+
+  /** Transport op to be applied post-parsing */
+  grpc_transport_op *post_parsing_op;
 };
 
 typedef struct {
@@ -417,7 +420,7 @@ typedef struct {
   /** HTTP2 stream id for this stream, or zero if one has not been assigned */
   uint32_t id;
   uint8_t fetching;
-  uint8_t sent_initial_metadata;
+  bool sent_initial_metadata;
   uint8_t sent_message;
   uint8_t sent_trailing_metadata;
   uint8_t read_closed;
@@ -509,7 +512,7 @@ void grpc_chttp2_publish_reads(grpc_exec_ctx *exec_ctx,
                                grpc_chttp2_transport_global *global,
                                grpc_chttp2_transport_parsing *parsing);
 
-void grpc_chttp2_list_add_writable_stream(
+bool grpc_chttp2_list_add_writable_stream(
     grpc_chttp2_transport_global *transport_global,
     grpc_chttp2_stream_global *stream_global);
 /** Get a writable stream
@@ -519,14 +522,13 @@ int grpc_chttp2_list_pop_writable_stream(
     grpc_chttp2_transport_writing *transport_writing,
     grpc_chttp2_stream_global **stream_global,
     grpc_chttp2_stream_writing **stream_writing);
-void grpc_chttp2_list_remove_writable_stream(
+bool grpc_chttp2_list_remove_writable_stream(
     grpc_chttp2_transport_global *transport_global,
-    grpc_chttp2_stream_global *stream_global);
+    grpc_chttp2_stream_global *stream_global) GRPC_MUST_USE_RESULT;
 
-/* returns 1 if stream added, 0 if it was already present */
-int grpc_chttp2_list_add_writing_stream(
+void grpc_chttp2_list_add_writing_stream(
     grpc_chttp2_transport_writing *transport_writing,
-    grpc_chttp2_stream_writing *stream_writing) GRPC_MUST_USE_RESULT;
+    grpc_chttp2_stream_writing *stream_writing);
 int grpc_chttp2_list_have_writing_streams(
     grpc_chttp2_transport_writing *transport_writing);
 int grpc_chttp2_list_pop_writing_stream(
@@ -770,4 +772,9 @@ void grpc_chttp2_ack_ping(grpc_exec_ctx *exec_ctx,
                           grpc_chttp2_transport_parsing *parsing,
                           const uint8_t *opaque_8bytes);
 
+/** add a ref to the stream and add it to the writable list;
+    ref will be dropped in writing.c */
+void grpc_chttp2_become_writable(grpc_chttp2_transport_global *transport_global,
+                                 grpc_chttp2_stream_global *stream_global);
+
 #endif
diff --git a/src/core/transport/chttp2/parsing.c b/src/core/transport/chttp2/parsing.c
index 8fdebd7f139857664cece6c5b27e12ca5cf57167..0516f39fa9ef83f84cf64a3e0e22c8cb839d7a14 100644
--- a/src/core/transport/chttp2/parsing.c
+++ b/src/core/transport/chttp2/parsing.c
@@ -1,6 +1,6 @@
 /*
  *
- * Copyright 2015, Google Inc.
+ * Copyright 2015-2016, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -149,7 +149,7 @@ void grpc_chttp2_publish_reads(
   if (was_zero && !is_zero) {
     while (grpc_chttp2_list_pop_stalled_by_transport(transport_global,
                                                      &stream_global)) {
-      grpc_chttp2_list_add_writable_stream(transport_global, stream_global);
+      grpc_chttp2_become_writable(transport_global, stream_global);
     }
   }
 
@@ -178,7 +178,7 @@ void grpc_chttp2_publish_reads(
                                  outgoing_window);
     is_zero = stream_global->outgoing_window <= 0;
     if (was_zero && !is_zero) {
-      grpc_chttp2_list_add_writable_stream(transport_global, stream_global);
+      grpc_chttp2_become_writable(transport_global, stream_global);
     }
 
     stream_global->max_recv_bytes -= (uint32_t)GPR_MIN(
diff --git a/src/core/transport/chttp2/stream_lists.c b/src/core/transport/chttp2/stream_lists.c
index b284c7881838174ea878075cc4bc547a59e3cc94..60fe735cfce9aa7327c5b90267154321780056d2 100644
--- a/src/core/transport/chttp2/stream_lists.c
+++ b/src/core/transport/chttp2/stream_lists.c
@@ -100,11 +100,14 @@ static void stream_list_remove(grpc_chttp2_transport *t, grpc_chttp2_stream *s,
   }
 }
 
-static void stream_list_maybe_remove(grpc_chttp2_transport *t,
+static bool stream_list_maybe_remove(grpc_chttp2_transport *t,
                                      grpc_chttp2_stream *s,
                                      grpc_chttp2_stream_list_id id) {
   if (s->included[id]) {
     stream_list_remove(t, s, id);
+    return true;
+  } else {
+    return false;
   }
 }
 
@@ -125,23 +128,24 @@ static void stream_list_add_tail(grpc_chttp2_transport *t,
   s->included[id] = 1;
 }
 
-static int stream_list_add(grpc_chttp2_transport *t, grpc_chttp2_stream *s,
-                           grpc_chttp2_stream_list_id id) {
+static bool stream_list_add(grpc_chttp2_transport *t, grpc_chttp2_stream *s,
+                            grpc_chttp2_stream_list_id id) {
   if (s->included[id]) {
-    return 0;
+    return false;
   }
   stream_list_add_tail(t, s, id);
-  return 1;
+  return true;
 }
 
 /* wrappers for specializations */
 
-void grpc_chttp2_list_add_writable_stream(
+bool grpc_chttp2_list_add_writable_stream(
     grpc_chttp2_transport_global *transport_global,
     grpc_chttp2_stream_global *stream_global) {
   GPR_ASSERT(stream_global->id != 0);
-  stream_list_add(TRANSPORT_FROM_GLOBAL(transport_global),
-                  STREAM_FROM_GLOBAL(stream_global), GRPC_CHTTP2_LIST_WRITABLE);
+  return stream_list_add(TRANSPORT_FROM_GLOBAL(transport_global),
+                         STREAM_FROM_GLOBAL(stream_global),
+                         GRPC_CHTTP2_LIST_WRITABLE);
 }
 
 int grpc_chttp2_list_pop_writable_stream(
@@ -159,20 +163,20 @@ int grpc_chttp2_list_pop_writable_stream(
   return r;
 }
 
-void grpc_chttp2_list_remove_writable_stream(
+bool grpc_chttp2_list_remove_writable_stream(
     grpc_chttp2_transport_global *transport_global,
     grpc_chttp2_stream_global *stream_global) {
-  stream_list_maybe_remove(TRANSPORT_FROM_GLOBAL(transport_global),
-                           STREAM_FROM_GLOBAL(stream_global),
-                           GRPC_CHTTP2_LIST_WRITABLE);
+  return stream_list_maybe_remove(TRANSPORT_FROM_GLOBAL(transport_global),
+                                  STREAM_FROM_GLOBAL(stream_global),
+                                  GRPC_CHTTP2_LIST_WRITABLE);
 }
 
-int grpc_chttp2_list_add_writing_stream(
+void grpc_chttp2_list_add_writing_stream(
     grpc_chttp2_transport_writing *transport_writing,
     grpc_chttp2_stream_writing *stream_writing) {
-  return stream_list_add(TRANSPORT_FROM_WRITING(transport_writing),
-                         STREAM_FROM_WRITING(stream_writing),
-                         GRPC_CHTTP2_LIST_WRITING);
+  GPR_ASSERT(stream_list_add(TRANSPORT_FROM_WRITING(transport_writing),
+                             STREAM_FROM_WRITING(stream_writing),
+                             GRPC_CHTTP2_LIST_WRITING));
 }
 
 int grpc_chttp2_list_have_writing_streams(
@@ -332,7 +336,7 @@ void grpc_chttp2_list_flush_writing_stalled_by_transport(
   while (stream_list_pop(transport, &stream,
                          GRPC_CHTTP2_LIST_WRITING_STALLED_BY_TRANSPORT)) {
     if (is_window_available) {
-      grpc_chttp2_list_add_writable_stream(&transport->global, &stream->global);
+      grpc_chttp2_become_writable(&transport->global, &stream->global);
     } else {
       grpc_chttp2_list_add_stalled_by_transport(transport_writing,
                                                 &stream->writing);
diff --git a/src/core/transport/chttp2/writing.c b/src/core/transport/chttp2/writing.c
index 356fd8174a76942b20e65409b63d049a0bcdacac..107725cbc797555d8e8d46d05f808faa84a1cc34 100644
--- a/src/core/transport/chttp2/writing.c
+++ b/src/core/transport/chttp2/writing.c
@@ -83,7 +83,8 @@ int grpc_chttp2_unlocking_check_writes(
      (according to available window sizes) and add to the output buffer */
   while (grpc_chttp2_list_pop_writable_stream(
       transport_global, transport_writing, &stream_global, &stream_writing)) {
-    uint8_t sent_initial_metadata;
+    bool sent_initial_metadata = stream_writing->sent_initial_metadata;
+    bool become_writable = false;
 
     stream_writing->id = stream_global->id;
     stream_writing->read_closed = stream_global->read_closed;
@@ -92,16 +93,12 @@ int grpc_chttp2_unlocking_check_writes(
                                  outgoing_window, stream_global,
                                  outgoing_window);
 
-    sent_initial_metadata = stream_writing->sent_initial_metadata;
     if (!sent_initial_metadata && stream_global->send_initial_metadata) {
       stream_writing->send_initial_metadata =
           stream_global->send_initial_metadata;
       stream_global->send_initial_metadata = NULL;
-      if (grpc_chttp2_list_add_writing_stream(transport_writing,
-                                              stream_writing)) {
-        GRPC_CHTTP2_STREAM_REF(stream_global, "chttp2_writing");
-      }
-      sent_initial_metadata = 1;
+      become_writable = true;
+      sent_initial_metadata = true;
     }
     if (sent_initial_metadata) {
       if (stream_global->send_message != NULL) {
@@ -128,10 +125,7 @@ int grpc_chttp2_unlocking_check_writes(
            stream_writing->flow_controlled_buffer.length > 0) &&
           stream_writing->outgoing_window > 0) {
         if (transport_writing->outgoing_window > 0) {
-          if (grpc_chttp2_list_add_writing_stream(transport_writing,
-                                                  stream_writing)) {
-            GRPC_CHTTP2_STREAM_REF(stream_global, "chttp2_writing");
-          }
+          become_writable = true;
         } else {
           grpc_chttp2_list_add_stalled_by_transport(transport_writing,
                                                     stream_writing);
@@ -141,10 +135,7 @@ int grpc_chttp2_unlocking_check_writes(
         stream_writing->send_trailing_metadata =
             stream_global->send_trailing_metadata;
         stream_global->send_trailing_metadata = NULL;
-        if (grpc_chttp2_list_add_writing_stream(transport_writing,
-                                                stream_writing)) {
-          GRPC_CHTTP2_STREAM_REF(stream_global, "chttp2_writing");
-        }
+        become_writable = true;
       }
     }
 
@@ -153,10 +144,13 @@ int grpc_chttp2_unlocking_check_writes(
       GRPC_CHTTP2_FLOW_MOVE_STREAM("write", transport_global, stream_writing,
                                    announce_window, stream_global,
                                    unannounced_incoming_window_for_writing);
-      if (grpc_chttp2_list_add_writing_stream(transport_writing,
-                                              stream_writing)) {
-        GRPC_CHTTP2_STREAM_REF(stream_global, "chttp2_writing");
-      }
+      become_writable = true;
+    }
+
+    if (become_writable) {
+      grpc_chttp2_list_add_writing_stream(transport_writing, stream_writing);
+    } else {
+      GRPC_CHTTP2_STREAM_UNREF(exec_ctx, stream_global, "chttp2_writing");
     }
   }
 
@@ -310,10 +304,7 @@ static void finalize_outbuf(grpc_exec_ctx *exec_ctx,
          (stream_writing->send_message && !stream_writing->fetching)) &&
         stream_writing->outgoing_window > 0) {
       if (transport_writing->outgoing_window > 0) {
-        if (grpc_chttp2_list_add_writing_stream(transport_writing,
-                                                stream_writing)) {
-          /* do nothing - already reffed */
-        }
+        grpc_chttp2_list_add_writing_stream(transport_writing, stream_writing);
       } else {
         grpc_chttp2_list_add_writing_stalled_by_transport(transport_writing,
                                                           stream_writing);
diff --git a/src/core/transport/chttp2_transport.c b/src/core/transport/chttp2_transport.c
index b9f511e9460fc1d1fc9c7c32d39a340ee58961f2..643e3feeb97e7582cbd10ddc31e721b812b34ecf 100644
--- a/src/core/transport/chttp2_transport.c
+++ b/src/core/transport/chttp2_transport.c
@@ -142,7 +142,7 @@ static void incoming_byte_stream_update_flow_control(
 static void fail_pending_writes(grpc_exec_ctx *exec_ctx,
                                 grpc_chttp2_stream_global *stream_global);
 
-/*
+/*******************************************************************************
  * CONSTRUCTION/DESTRUCTION/REFCOUNTING
  */
 
@@ -521,7 +521,6 @@ static void destroy_stream(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
                                            s->global.id) == NULL);
   }
 
-  grpc_chttp2_list_remove_writable_stream(&t->global, &s->global);
   grpc_chttp2_list_remove_unannounced_incoming_window_available(&t->global,
                                                                 &s->global);
   grpc_chttp2_list_remove_stalled_by_transport(&t->global, &s->global);
@@ -583,7 +582,7 @@ grpc_chttp2_stream_parsing *grpc_chttp2_parsing_accept_stream(
   return &accepting->parsing;
 }
 
-/*
+/*******************************************************************************
  * LOCK MANAGEMENT
  */
 
@@ -611,10 +610,18 @@ static void unlock(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t) {
   GPR_TIMER_END("unlock", 0);
 }
 
-/*
+/*******************************************************************************
  * OUTPUT PROCESSING
  */
 
+void grpc_chttp2_become_writable(grpc_chttp2_transport_global *transport_global,
+                                 grpc_chttp2_stream_global *stream_global) {
+  if (!TRANSPORT_FROM_GLOBAL(transport_global)->closed &&
+      grpc_chttp2_list_add_writable_stream(transport_global, stream_global)) {
+    GRPC_CHTTP2_STREAM_REF(stream_global, "chttp2_writing");
+  }
+}
+
 static void push_setting(grpc_chttp2_transport *t, grpc_chttp2_setting_id id,
                          uint32_t value) {
   const grpc_chttp2_setting_parameters *sp =
@@ -732,7 +739,7 @@ static void maybe_start_some_streams(
         stream_global->id, STREAM_FROM_GLOBAL(stream_global));
     stream_global->in_stream_map = 1;
     transport_global->concurrent_stream_count++;
-    grpc_chttp2_list_add_writable_stream(transport_global, stream_global);
+    grpc_chttp2_become_writable(transport_global, stream_global);
   }
   /* cancel out streams that will never be started */
   while (transport_global->next_stream_id >= MAX_CLIENT_STREAM_ID &&
@@ -821,7 +828,7 @@ static void perform_stream_op_locked(
         maybe_start_some_streams(exec_ctx, transport_global);
       } else {
         GPR_ASSERT(stream_global->id != 0);
-        grpc_chttp2_list_add_writable_stream(transport_global, stream_global);
+        grpc_chttp2_become_writable(transport_global, stream_global);
       }
     } else {
       grpc_chttp2_complete_closure_step(
@@ -838,7 +845,7 @@ static void perform_stream_op_locked(
           exec_ctx, &stream_global->send_message_finished, 0);
     } else if (stream_global->id != 0) {
       stream_global->send_message = op->send_message;
-      grpc_chttp2_list_add_writable_stream(transport_global, stream_global);
+      grpc_chttp2_become_writable(transport_global, stream_global);
     }
   }
 
@@ -858,7 +865,7 @@ static void perform_stream_op_locked(
     } else if (stream_global->id != 0) {
       /* TODO(ctiller): check if there's flow control for any outstanding
          bytes before going writable */
-      grpc_chttp2_list_add_writable_stream(transport_global, stream_global);
+      grpc_chttp2_become_writable(transport_global, stream_global);
     }
   }
 
@@ -944,12 +951,10 @@ void grpc_chttp2_ack_ping(grpc_exec_ctx *exec_ctx,
   unlock(exec_ctx, t);
 }
 
-static void perform_transport_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
-                                 grpc_transport_op *op) {
-  grpc_chttp2_transport *t = (grpc_chttp2_transport *)gt;
-  int close_transport = 0;
-
-  lock(t);
+static void perform_transport_op_locked(grpc_exec_ctx *exec_ctx,
+                                        grpc_chttp2_transport *t,
+                                        grpc_transport_op *op) {
+  bool close_transport = false;
 
   grpc_exec_ctx_enqueue(exec_ctx, op->on_consumed, true, NULL);
 
@@ -968,8 +973,8 @@ static void perform_transport_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
     close_transport = !grpc_chttp2_has_streams(t);
   }
 
-  if (op->set_accept_stream != NULL) {
-    t->channel_callback.accept_stream = op->set_accept_stream;
+  if (op->set_accept_stream) {
+    t->channel_callback.accept_stream = op->set_accept_stream_fn;
     t->channel_callback.accept_stream_user_data =
         op->set_accept_stream_user_data;
   }
@@ -990,16 +995,31 @@ static void perform_transport_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
     close_transport_locked(exec_ctx, t);
   }
 
-  unlock(exec_ctx, t);
-
   if (close_transport) {
-    lock(t);
     close_transport_locked(exec_ctx, t);
-    unlock(exec_ctx, t);
   }
 }
 
-/*
+static void perform_transport_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
+                                 grpc_transport_op *op) {
+  grpc_chttp2_transport *t = (grpc_chttp2_transport *)gt;
+
+  lock(t);
+
+  /* If there's a set_accept_stream ensure that we're not parsing
+     to avoid changing things out from underneath */
+  if (t->parsing_active && op->set_accept_stream) {
+    GPR_ASSERT(t->post_parsing_op == NULL);
+    t->post_parsing_op = gpr_malloc(sizeof(*op));
+    memcpy(t->post_parsing_op, op, sizeof(*op));
+  } else {
+    perform_transport_op_locked(exec_ctx, t, op);
+  }
+
+  unlock(exec_ctx, t);
+}
+
+/*******************************************************************************
  * INPUT PROCESSING
  */
 
@@ -1064,7 +1084,6 @@ static void remove_stream(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
   if (!s) {
     s = grpc_chttp2_stream_map_delete(&t->new_stream_map, id);
   }
-  grpc_chttp2_list_remove_writable_stream(&t->global, &s->global);
   GPR_ASSERT(s);
   s->global.in_stream_map = 0;
   if (t->parsing.incoming_stream == &s->parsing) {
@@ -1080,6 +1099,9 @@ static void remove_stream(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
   if (grpc_chttp2_unregister_stream(t, s) && t->global.sent_goaway) {
     close_transport_locked(exec_ctx, t);
   }
+  if (grpc_chttp2_list_remove_writable_stream(&t->global, &s->global)) {
+    GRPC_CHTTP2_STREAM_UNREF(exec_ctx, &s->global, "chttp2_writing");
+  }
 
   new_stream_count = grpc_chttp2_stream_map_size(&t->parsing_stream_map) +
                      grpc_chttp2_stream_map_size(&t->new_stream_map);
@@ -1331,7 +1353,7 @@ static void update_global_window(void *args, uint32_t id, void *stream) {
   is_zero = stream_global->outgoing_window <= 0;
 
   if (was_zero && !is_zero) {
-    grpc_chttp2_list_add_writable_stream(transport_global, stream_global);
+    grpc_chttp2_become_writable(transport_global, stream_global);
   }
 }
 
@@ -1392,6 +1414,13 @@ static void recv_data(grpc_exec_ctx *exec_ctx, void *tp, bool success) {
     /* handle higher level things */
     grpc_chttp2_publish_reads(exec_ctx, transport_global, transport_parsing);
     t->parsing_active = 0;
+    /* handle delayed transport ops (if there is one) */
+    if (t->post_parsing_op) {
+      grpc_transport_op *op = t->post_parsing_op;
+      t->post_parsing_op = NULL;
+      perform_transport_op_locked(exec_ctx, t, op);
+      gpr_free(op);
+    }
     /* if a stream is in the stream map, and gets cancelled, we need to ensure
      * we are not parsing before continuing the cancellation to keep things in
      * a sane state */
@@ -1426,7 +1455,7 @@ static void recv_data(grpc_exec_ctx *exec_ctx, void *tp, bool success) {
   GPR_TIMER_END("recv_data", 0);
 }
 
-/*
+/*******************************************************************************
  * CALLBACK LOOP
  */
 
@@ -1440,7 +1469,7 @@ static void connectivity_state_set(
                               state, reason);
 }
 
-/*
+/*******************************************************************************
  * POLLSET STUFF
  */
 
@@ -1468,7 +1497,7 @@ static void set_pollset(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
   unlock(exec_ctx, t);
 }
 
-/*
+/*******************************************************************************
  * BYTE STREAM
  */
 
@@ -1508,7 +1537,7 @@ static void incoming_byte_stream_update_flow_control(
                                    add_max_recv_bytes);
     grpc_chttp2_list_add_unannounced_incoming_window_available(transport_global,
                                                                stream_global);
-    grpc_chttp2_list_add_writable_stream(transport_global, stream_global);
+    grpc_chttp2_become_writable(transport_global, stream_global);
   }
 }
 
@@ -1623,7 +1652,7 @@ grpc_chttp2_incoming_byte_stream *grpc_chttp2_incoming_byte_stream_create(
   return incoming_byte_stream;
 }
 
-/*
+/*******************************************************************************
  * TRACING
  */
 
@@ -1709,7 +1738,7 @@ void grpc_chttp2_flowctl_trace(const char *file, int line, const char *phase,
   gpr_free(prefix);
 }
 
-/*
+/*******************************************************************************
  * INTEGRATION GLUE
  */
 
diff --git a/src/core/transport/metadata.c b/src/core/transport/metadata.c
index 14912af7df1cafddded3581dac73f1ba57d74ed0..807ae071a309627b16f73ccee0b48c893b6896bb 100644
--- a/src/core/transport/metadata.c
+++ b/src/core/transport/metadata.c
@@ -43,11 +43,13 @@
 #include <grpc/support/log.h>
 #include <grpc/support/string_util.h>
 #include <grpc/support/time.h>
+
 #include "src/core/profiling/timers.h"
 #include "src/core/support/murmur_hash.h"
 #include "src/core/support/string.h"
 #include "src/core/transport/chttp2/bin_encoder.h"
 #include "src/core/transport/static_metadata.h"
+#include "src/core/iomgr/iomgr_internal.h"
 
 /* There are two kinds of mdelem and mdstr instances.
  * Static instances are declared in static_metadata.{h,c} and
@@ -227,6 +229,9 @@ void grpc_mdctx_global_shutdown(void) {
     if (shard->count != 0) {
       gpr_log(GPR_DEBUG, "WARNING: %d metadata elements were leaked",
               shard->count);
+      if (grpc_iomgr_abort_on_leaks()) {
+        abort();
+      }
     }
     gpr_free(shard->elems);
   }
@@ -237,6 +242,9 @@ void grpc_mdctx_global_shutdown(void) {
     if (shard->count != 0) {
       gpr_log(GPR_DEBUG, "WARNING: %d metadata strings were leaked",
               shard->count);
+      if (grpc_iomgr_abort_on_leaks()) {
+        abort();
+      }
     }
     gpr_free(shard->strs);
   }
diff --git a/src/core/transport/transport.c b/src/core/transport/transport.c
index 6e154b629ab872ab57a4561d822094cf8baa2982..3b555fa9338c3eb9c7f453f14efe45fe6212db5d 100644
--- a/src/core/transport/transport.c
+++ b/src/core/transport/transport.c
@@ -45,7 +45,7 @@ void grpc_stream_ref(grpc_stream_refcount *refcount, const char *reason) {
 #else
 void grpc_stream_ref(grpc_stream_refcount *refcount) {
 #endif
-  gpr_ref(&refcount->refs);
+  gpr_ref_non_zero(&refcount->refs);
 }
 
 #ifdef GRPC_STREAM_REFCOUNT_DEBUG
diff --git a/src/core/transport/transport.h b/src/core/transport/transport.h
index 8902c5d2f65f886e5535bc2fe2edc2631aee2941..ed6e121c9cbb685e4b7e109a7f92110320f9c424 100644
--- a/src/core/transport/transport.h
+++ b/src/core/transport/transport.h
@@ -123,7 +123,7 @@ typedef struct grpc_transport_stream_op {
 
 /** Transport op: a set of operations to perform on a transport as a whole */
 typedef struct grpc_transport_op {
-  /** called when processing of this op is done */
+  /** Called when processing of this op is done. */
   grpc_closure *on_consumed;
   /** connectivity monitoring - set connectivity_state to NULL to unsubscribe */
   grpc_closure *on_connectivity_state_change;
@@ -138,9 +138,13 @@ typedef struct grpc_transport_op {
   grpc_status_code goaway_status;
   gpr_slice *goaway_message;
   /** set the callback for accepting new streams;
-      this is a permanent callback, unlike the other one-shot closures */
-  void (*set_accept_stream)(grpc_exec_ctx *exec_ctx, void *user_data,
-                            grpc_transport *transport, const void *server_data);
+      this is a permanent callback, unlike the other one-shot closures.
+      If true, the callback is set to set_accept_stream_fn, with its
+      user_data argument set to set_accept_stream_user_data */
+  bool set_accept_stream;
+  void (*set_accept_stream_fn)(grpc_exec_ctx *exec_ctx, void *user_data,
+                               grpc_transport *transport,
+                               const void *server_data);
   void *set_accept_stream_user_data;
   /** add this transport to a pollset */
   grpc_pollset *bind_pollset;
diff --git a/src/python/grpcio/grpc/_cython/imports.generated.c b/src/python/grpcio/grpc/_cython/imports.generated.c
index 4b1860ce8c9ef6ebe0d14534b0fa6ad7fcb53d3b..8bd6ae6372b02ff16257cc556123be1f322926ca 100644
--- a/src/python/grpcio/grpc/_cython/imports.generated.c
+++ b/src/python/grpcio/grpc/_cython/imports.generated.c
@@ -220,6 +220,7 @@ gpr_event_get_type gpr_event_get_import;
 gpr_event_wait_type gpr_event_wait_import;
 gpr_ref_init_type gpr_ref_init_import;
 gpr_ref_type gpr_ref_import;
+gpr_ref_non_zero_type gpr_ref_non_zero_import;
 gpr_refn_type gpr_refn_import;
 gpr_unref_type gpr_unref_import;
 gpr_stats_init_type gpr_stats_init_import;
@@ -485,6 +486,7 @@ void pygrpc_load_imports(HMODULE library) {
   gpr_event_wait_import = (gpr_event_wait_type) GetProcAddress(library, "gpr_event_wait");
   gpr_ref_init_import = (gpr_ref_init_type) GetProcAddress(library, "gpr_ref_init");
   gpr_ref_import = (gpr_ref_type) GetProcAddress(library, "gpr_ref");
+  gpr_ref_non_zero_import = (gpr_ref_non_zero_type) GetProcAddress(library, "gpr_ref_non_zero");
   gpr_refn_import = (gpr_refn_type) GetProcAddress(library, "gpr_refn");
   gpr_unref_import = (gpr_unref_type) GetProcAddress(library, "gpr_unref");
   gpr_stats_init_import = (gpr_stats_init_type) GetProcAddress(library, "gpr_stats_init");
diff --git a/src/python/grpcio/grpc/_cython/imports.generated.h b/src/python/grpcio/grpc/_cython/imports.generated.h
index a395dce7d6a4c3801ef7c5f1863befc50a376fc6..b70dcccd17a9f7a923bcf57a22e41301ff342469 100644
--- a/src/python/grpcio/grpc/_cython/imports.generated.h
+++ b/src/python/grpcio/grpc/_cython/imports.generated.h
@@ -610,6 +610,9 @@ extern gpr_ref_init_type gpr_ref_init_import;
 typedef void(*gpr_ref_type)(gpr_refcount *r);
 extern gpr_ref_type gpr_ref_import;
 #define gpr_ref gpr_ref_import
+typedef void(*gpr_ref_non_zero_type)(gpr_refcount *r);
+extern gpr_ref_non_zero_type gpr_ref_non_zero_import;
+#define gpr_ref_non_zero gpr_ref_non_zero_import
 typedef void(*gpr_refn_type)(gpr_refcount *r, int n);
 extern gpr_refn_type gpr_refn_import;
 #define gpr_refn gpr_refn_import
diff --git a/src/python/grpcio/tests/_runner.py b/src/python/grpcio/tests/_runner.py
index 4f1ddb57fcfa0956c418314a075ff66c793ea9da..38a5432e791790db21eb4cff98a4c8d17b51a0e2 100644
--- a/src/python/grpcio/tests/_runner.py
+++ b/src/python/grpcio/tests/_runner.py
@@ -1,4 +1,4 @@
-# Copyright 2015, Google Inc.
+# Copyright 2015-2016, Google Inc.
 # All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
@@ -143,10 +143,17 @@ class Runner(object):
 
   def run(self, suite):
     """See setuptools' test_runner setup argument for information."""
+    # only run test cases with id starting with given prefix
+    testcase_filter = os.getenv('GPRC_PYTHON_TESTRUNNER_FILTER')
+    filtered_cases = []
+    for case in _loader.iterate_suite_cases(suite):
+      if not testcase_filter or case.id().startswith(testcase_filter):
+        filtered_cases.append(case)
+
     # Ensure that every test case has no collision with any other test case in
     # the augmented results.
     augmented_cases = [AugmentedCase(case, uuid.uuid4())
-                       for case in _loader.iterate_suite_cases(suite)]
+                       for case in filtered_cases]
     case_id_by_case = dict((augmented_case.case, augmented_case.id)
                            for augmented_case in augmented_cases)
     result_out = StringIO.StringIO()
diff --git a/src/python/grpcio/tests/tests.json b/src/python/grpcio/tests/tests.json
new file mode 100644
index 0000000000000000000000000000000000000000..388d040d5caa67c97da8352c2d1a4539b689c00a
--- /dev/null
+++ b/src/python/grpcio/tests/tests.json
@@ -0,0 +1,62 @@
+[
+  "_base_interface_test.AsyncEasyTest", 
+  "_base_interface_test.AsyncPeasyTest", 
+  "_base_interface_test.SyncEasyTest", 
+  "_base_interface_test.SyncPeasyTest", 
+  "_beta_features_test.BetaFeaturesTest", 
+  "_beta_features_test.ContextManagementAndLifecycleTest", 
+  "_channel_test.ChannelTest", 
+  "_connectivity_channel_test.ChannelConnectivityTest", 
+  "_core_over_links_base_interface_test.AsyncEasyTest", 
+  "_core_over_links_base_interface_test.AsyncPeasyTest", 
+  "_core_over_links_base_interface_test.SyncEasyTest", 
+  "_core_over_links_base_interface_test.SyncPeasyTest", 
+  "_crust_over_core_face_interface_test.DynamicInvokerBlockingInvocationInlineServiceTest", 
+  "_crust_over_core_face_interface_test.DynamicInvokerEventInvocationSynchronousEventServiceTest", 
+  "_crust_over_core_face_interface_test.DynamicInvokerFutureInvocationAsynchronousEventServiceTest", 
+  "_crust_over_core_face_interface_test.GenericInvokerBlockingInvocationInlineServiceTest", 
+  "_crust_over_core_face_interface_test.GenericInvokerEventInvocationSynchronousEventServiceTest", 
+  "_crust_over_core_face_interface_test.GenericInvokerFutureInvocationAsynchronousEventServiceTest", 
+  "_crust_over_core_face_interface_test.MultiCallableInvokerBlockingInvocationInlineServiceTest", 
+  "_crust_over_core_face_interface_test.MultiCallableInvokerEventInvocationSynchronousEventServiceTest", 
+  "_crust_over_core_face_interface_test.MultiCallableInvokerFutureInvocationAsynchronousEventServiceTest", 
+  "_crust_over_core_over_links_face_interface_test.DynamicInvokerBlockingInvocationInlineServiceTest", 
+  "_crust_over_core_over_links_face_interface_test.DynamicInvokerEventInvocationSynchronousEventServiceTest", 
+  "_crust_over_core_over_links_face_interface_test.DynamicInvokerFutureInvocationAsynchronousEventServiceTest", 
+  "_crust_over_core_over_links_face_interface_test.GenericInvokerBlockingInvocationInlineServiceTest", 
+  "_crust_over_core_over_links_face_interface_test.GenericInvokerEventInvocationSynchronousEventServiceTest", 
+  "_crust_over_core_over_links_face_interface_test.GenericInvokerFutureInvocationAsynchronousEventServiceTest", 
+  "_crust_over_core_over_links_face_interface_test.MultiCallableInvokerBlockingInvocationInlineServiceTest", 
+  "_crust_over_core_over_links_face_interface_test.MultiCallableInvokerEventInvocationSynchronousEventServiceTest", 
+  "_crust_over_core_over_links_face_interface_test.MultiCallableInvokerFutureInvocationAsynchronousEventServiceTest", 
+  "_face_interface_test.DynamicInvokerBlockingInvocationInlineServiceTest", 
+  "_face_interface_test.DynamicInvokerEventInvocationSynchronousEventServiceTest", 
+  "_face_interface_test.DynamicInvokerFutureInvocationAsynchronousEventServiceTest", 
+  "_face_interface_test.GenericInvokerBlockingInvocationInlineServiceTest", 
+  "_face_interface_test.GenericInvokerEventInvocationSynchronousEventServiceTest", 
+  "_face_interface_test.GenericInvokerFutureInvocationAsynchronousEventServiceTest", 
+  "_face_interface_test.MultiCallableInvokerBlockingInvocationInlineServiceTest", 
+  "_face_interface_test.MultiCallableInvokerEventInvocationSynchronousEventServiceTest", 
+  "_face_interface_test.MultiCallableInvokerFutureInvocationAsynchronousEventServiceTest", 
+  "_implementations_test.ChannelCredentialsTest", 
+  "_insecure_interop_test.InsecureInteropTest", 
+  "_intermediary_low_test.CancellationTest", 
+  "_intermediary_low_test.EchoTest", 
+  "_intermediary_low_test.ExpirationTest", 
+  "_intermediary_low_test.LonelyClientTest", 
+  "_later_test.LaterTest", 
+  "_logging_pool_test.LoggingPoolTest", 
+  "_lonely_invocation_link_test.LonelyInvocationLinkTest", 
+  "_low_test.HangingServerShutdown", 
+  "_low_test.InsecureServerInsecureClient", 
+  "_not_found_test.NotFoundTest", 
+  "_sanity_test.Sanity", 
+  "_secure_interop_test.SecureInteropTest", 
+  "_transmission_test.RoundTripTest", 
+  "_transmission_test.TransmissionTest", 
+  "_utilities_test.ChannelConnectivityTest", 
+  "beta_python_plugin_test.PythonPluginTest", 
+  "cygrpc_test.InsecureServerInsecureClient", 
+  "cygrpc_test.SecureServerSecureClient", 
+  "cygrpc_test.TypeSmokeTest"
+]
\ No newline at end of file
diff --git a/src/python/grpcio/tests/unit/_sanity/__init__.py b/src/python/grpcio/tests/unit/_sanity/__init__.py
new file mode 100644
index 0000000000000000000000000000000000000000..2f88fa04122d292e57bd1fa0da8d2a65dad35f61
--- /dev/null
+++ b/src/python/grpcio/tests/unit/_sanity/__init__.py
@@ -0,0 +1,30 @@
+# Copyright 2016, Google Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
diff --git a/src/python/grpcio/tests/unit/_sanity/_sanity_test.py b/src/python/grpcio/tests/unit/_sanity/_sanity_test.py
new file mode 100644
index 0000000000000000000000000000000000000000..0a5a715c0e1c66bfcff7a05cbcb9238941e2e4aa
--- /dev/null
+++ b/src/python/grpcio/tests/unit/_sanity/_sanity_test.py
@@ -0,0 +1,53 @@
+# Copyright 2016, Google Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+import json
+import unittest
+
+import tests
+
+
+class Sanity(unittest.TestCase):
+
+  def testTestsJsonUpToDate(self):
+    """Autodiscovers all test suites and checks that tests.json is up to date"""
+    loader = tests.Loader()
+    loader.loadTestsFromNames(['tests'])
+    test_suite_names = [
+        test_case_class.id().rsplit('.', 1)[0]
+        for test_case_class in tests._loader.iterate_suite_cases(loader.suite)]
+    test_suite_names = sorted(set(test_suite_names))
+
+    with open('src/python/grpcio/tests/tests.json') as tests_json_file:
+      tests_json = json.load(tests_json_file)
+    self.assertListEqual(test_suite_names, tests_json)
+
+
+if __name__ == '__main__':
+  unittest.main(verbosity=2)
diff --git a/src/ruby/ext/grpc/rb_grpc_imports.generated.c b/src/ruby/ext/grpc/rb_grpc_imports.generated.c
index 1af34d97fbcd8239edbe26e595cef8d92ba59bfd..56db4ec686b5fb8ccecdcebf61bdd0bcfbf01b9c 100644
--- a/src/ruby/ext/grpc/rb_grpc_imports.generated.c
+++ b/src/ruby/ext/grpc/rb_grpc_imports.generated.c
@@ -220,6 +220,7 @@ gpr_event_get_type gpr_event_get_import;
 gpr_event_wait_type gpr_event_wait_import;
 gpr_ref_init_type gpr_ref_init_import;
 gpr_ref_type gpr_ref_import;
+gpr_ref_non_zero_type gpr_ref_non_zero_import;
 gpr_refn_type gpr_refn_import;
 gpr_unref_type gpr_unref_import;
 gpr_stats_init_type gpr_stats_init_import;
@@ -481,6 +482,7 @@ void grpc_rb_load_imports(HMODULE library) {
   gpr_event_wait_import = (gpr_event_wait_type) GetProcAddress(library, "gpr_event_wait");
   gpr_ref_init_import = (gpr_ref_init_type) GetProcAddress(library, "gpr_ref_init");
   gpr_ref_import = (gpr_ref_type) GetProcAddress(library, "gpr_ref");
+  gpr_ref_non_zero_import = (gpr_ref_non_zero_type) GetProcAddress(library, "gpr_ref_non_zero");
   gpr_refn_import = (gpr_refn_type) GetProcAddress(library, "gpr_refn");
   gpr_unref_import = (gpr_unref_type) GetProcAddress(library, "gpr_unref");
   gpr_stats_init_import = (gpr_stats_init_type) GetProcAddress(library, "gpr_stats_init");
diff --git a/src/ruby/ext/grpc/rb_grpc_imports.generated.h b/src/ruby/ext/grpc/rb_grpc_imports.generated.h
index 38aabfaca8f20d7c83a51d2f4b8314639e085a79..b972f60fc3584dbed102d5b306f451b9ac14634a 100644
--- a/src/ruby/ext/grpc/rb_grpc_imports.generated.h
+++ b/src/ruby/ext/grpc/rb_grpc_imports.generated.h
@@ -610,6 +610,9 @@ extern gpr_ref_init_type gpr_ref_init_import;
 typedef void(*gpr_ref_type)(gpr_refcount *r);
 extern gpr_ref_type gpr_ref_import;
 #define gpr_ref gpr_ref_import
+typedef void(*gpr_ref_non_zero_type)(gpr_refcount *r);
+extern gpr_ref_non_zero_type gpr_ref_non_zero_import;
+#define gpr_ref_non_zero gpr_ref_non_zero_import
 typedef void(*gpr_refn_type)(gpr_refcount *r, int n);
 extern gpr_refn_type gpr_refn_import;
 #define gpr_refn gpr_refn_import
diff --git a/tools/README.md b/tools/README.md
index a0c41eb79ffcdfea58e15b1d35a18e8cb4ab3210..df4c6ef7d2527e7c4c3fe6a632815918e5d4f726 100644
--- a/tools/README.md
+++ b/tools/README.md
@@ -1,7 +1,5 @@
 buildgen: template renderer for our build system.
 
-distpackages: script to generate debian packages.
-
 distrib: scripts to distribute language-specific packages.
 
 dockerfile: Docker files to test gRPC.
@@ -12,6 +10,4 @@ gce: scripts to help setup testing infrastructure on GCE.
 
 jenkins: support for running tests on Jenkins.
 
-profile_analyzer: pretty printer for gRPC profiling data.
-
 run_tests: scripts to run gRPC tests in parallel.
diff --git a/tools/run_tests/build_node.bat b/tools/run_tests/build_node.bat
index 6896bc1d1bb1480ea66c222390b9a5104168d367..886af0610ff8f78e4ecd57fcee504f21f18a06a7 100644
--- a/tools/run_tests/build_node.bat
+++ b/tools/run_tests/build_node.bat
@@ -27,4 +27,16 @@
 @rem (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 @rem OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-npm install --build-from-source
\ No newline at end of file
+set PATH=%PATH%;C:\Program Files\nodejs\;%APPDATA%\npm
+
+del /f /q BUILD || rmdir build /s /q
+
+call npm install --build-from-source
+
+@rem delete the redundant openssl headers
+for /f "delims=v" %%v in ('node --version') do (
+  rmdir "%HOMEDRIVE%%HOMEPATH%\.node-gyp\%%v\include\node\openssl" /S /Q
+)
+
+@rem rebuild, because it probably failed the first time
+call npm install --build-from-source
\ No newline at end of file
diff --git a/tools/run_tests/build_python.sh b/tools/run_tests/build_python.sh
index e0fcbb602d4bc276e3b7ccb6caa7ed1101634c73..f120fc7ed6905ecc896d6dfcf2d7eaa82b9a9124 100755
--- a/tools/run_tests/build_python.sh
+++ b/tools/run_tests/build_python.sh
@@ -45,3 +45,6 @@ export GRPC_PYTHON_ENABLE_CYTHON_TRACING=1
 tox --notest
 
 $ROOT/.tox/py27/bin/python $ROOT/setup.py build
+$ROOT/.tox/py27/bin/python $ROOT/setup.py build_py
+$ROOT/.tox/py27/bin/python $ROOT/setup.py build_ext --inplace
+$ROOT/.tox/py27/bin/python $ROOT/setup.py gather --test
diff --git a/tools/run_tests/pre_build_node.bat b/tools/run_tests/pre_build_node.bat
index 6e7cbe5d420d58060f8c26dbc9b5953f92e9ee1c..a29456f9ed95eecbca0e2b86b04168ff09ca989b 100644
--- a/tools/run_tests/pre_build_node.bat
+++ b/tools/run_tests/pre_build_node.bat
@@ -27,13 +27,8 @@
 @rem (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 @rem OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-@rem Expire cache after 1 week
-npm update --cache-min 604800
+set PATH=%PATH%;C:\Program Files\nodejs\;%APPDATA%\npm
 
-npm install node-gyp-install
-.\node_modules\.bin\node-gyp-install.cmd
+@rem Expire cache after 1 week
+call npm update --cache-min 604800
 
-@rem delete the redundant openssl headers
-for /f "delims=v" %%v in ('node --version') do (
-  rmdir "%HOMEDRIVE%%HOMEPATH%\.node-gyp\%%v\include\node\openssl" /S /Q
-)
\ No newline at end of file
diff --git a/tools/run_tests/run_interop_tests.py b/tools/run_tests/run_interop_tests.py
index df3ab90a839fad5e10d73847a2f12c3951841809..1dc772a85658157e6794793e16075719de655982 100755
--- a/tools/run_tests/run_interop_tests.py
+++ b/tools/run_tests/run_interop_tests.py
@@ -60,6 +60,8 @@ _SKIP_COMPRESSION = ['large_compressed_unary',
 _SKIP_ADVANCED = ['custom_metadata', 'status_code_and_message',
                   'unimplemented_method']
 
+_TEST_TIMEOUT = 3*60
+
 class CXXLanguage:
 
   def __init__(self):
@@ -459,7 +461,7 @@ def cloud_to_prod_jobspec(language, test_case, server_host_name,
           environ=environ,
           shortname='%s:%s:%s:%s' % (suite_name, server_host_name, language,
                                      test_case),
-          timeout_seconds=90,
+          timeout_seconds=_TEST_TIMEOUT,
           flake_retries=5 if args.allow_flakes else 0,
           timeout_retries=2 if args.allow_flakes else 0,
           kill_handler=_job_kill_handler)
@@ -495,7 +497,7 @@ def cloud_to_cloud_jobspec(language, test_case, server_name, server_host,
           environ=environ,
           shortname='cloud_to_cloud:%s:%s_server:%s' % (language, server_name,
                                                         test_case),
-          timeout_seconds=90,
+          timeout_seconds=_TEST_TIMEOUT,
           flake_retries=5 if args.allow_flakes else 0,
           timeout_retries=2 if args.allow_flakes else 0,
           kill_handler=_job_kill_handler)
diff --git a/tools/run_tests/run_node.bat b/tools/run_tests/run_node.bat
index 41777363568ae3387a3951d99730901fd0627cb1..0987fbee55992a1565a6462d07feeb1aa243699f 100644
--- a/tools/run_tests/run_node.bat
+++ b/tools/run_tests/run_node.bat
@@ -27,6 +27,7 @@
 @rem (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 @rem OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+set PATH=%PATH%;C:\Program Files\nodejs\;%APPDATA%\npm
 set JUNIT_REPORT_PATH=src\node\report.xml
 set JUNIT_REPORT_STACK=1
 .\node_modules\.bin\mocha.cmd --reporter mocha-jenkins-reporter --timeout 8000 src\node\test
\ No newline at end of file
diff --git a/tools/run_tests/run_python.sh b/tools/run_tests/run_python.sh
index ffe9c12af1a2beefc6cf9773cd9f46412059fcba..beb747a6169aca6a64380a29cf4e695ea070e474 100755
--- a/tools/run_tests/run_python.sh
+++ b/tools/run_tests/run_python.sh
@@ -42,7 +42,12 @@ export LDFLAGS="-L$ROOT/libs/$CONFIG"
 export GRPC_PYTHON_BUILD_WITH_CYTHON=1
 export GRPC_PYTHON_ENABLE_CYTHON_TRACING=1
 
-tox
+if [ "$CONFIG" = "gcov" ]
+then
+  tox
+else
+  $ROOT/.tox/py27/bin/python $ROOT/setup.py test
+fi
 
 mkdir -p $ROOT/reports
 rm -rf $ROOT/reports/python-coverage
diff --git a/tools/run_tests/run_tests.py b/tools/run_tests/run_tests.py
index 08a5ff0e8fafbc0757c5bd9eee1081c23b4355ba..c55d1fbe6334823788df6d7703b3fb466881526e 100755
--- a/tools/run_tests/run_tests.py
+++ b/tools/run_tests/run_tests.py
@@ -353,15 +353,27 @@ class PythonLanguage(object):
     _check_compiler(self.args.compiler, ['default'])
 
   def test_specs(self):
+    # load list of known test suites
+    with open('src/python/grpcio/tests/tests.json') as tests_json_file:
+      tests_json = json.load(tests_json_file)
     environment = dict(_FORCE_ENVIRON_FOR_WRAPPERS)
     environment['PYVER'] = '2.7'
-    return [self.config.job_spec(
-        ['tools/run_tests/run_python.sh'],
-        None,
-        environ=environment,
-        shortname='py.test',
-        timeout_seconds=15*60
-    )]
+    if self.config.build_config != 'gcov':
+      return [self.config.job_spec(
+          ['tools/run_tests/run_python.sh'],
+          None,
+          environ=dict(environment.items() +
+                       [('GPRC_PYTHON_TESTRUNNER_FILTER', suite_name)]),
+          shortname='py.test.%s' % suite_name,
+          timeout_seconds=5*60)
+          for suite_name in tests_json]
+    else:
+      return [self.config.job_spec(['tools/run_tests/run_python.sh'],
+                                   None,
+                                   environ=environment,
+                                   shortname='py.test.coverage',
+                                   timeout_seconds=15*60)]
+
 
   def pre_build_steps(self):
     return []