diff --git a/lib/cpp/src/TLogging.h b/lib/cpp/src/TLogging.h
index 54cccbe..2c23f0a 100644
--- a/lib/cpp/src/TLogging.h
+++ b/lib/cpp/src/TLogging.h
@@ -162,24 +162,38 @@
 
 
 /**
- * T_GLOBAL_DEBUG_VIRTUAL = 0: normal operation,
- *                             virtual call debug messages disabled
- * T_GLOBAL_DEBUG_VIRTUAL = 1: log a debug messages whenever an
- *                             avoidable virtual call is made
+ * T_GLOBAL_DEBUG_VIRTUAL = 0 or unset: normal operation,
+ *                                      virtual call debug messages disabled
+ * T_GLOBAL_DEBUG_VIRTUAL = 1:          log a debug messages whenever an
+ *                                      avoidable virtual call is made
+ * T_GLOBAL_DEBUG_VIRTUAL = 2:          record detailed info that can be
+ *                                      printed by calling
+ *                                      apache::thrift::profile_print_info()
  */
-#define T_GLOBAL_DEBUG_VIRTUAL 0
-
-/**
- * Log a message indicating that a virtual function call is being made.
- *
- * This should be disabled during normal use.  It is intended to be used
- * only to help debug serialization performance.
- */
-#if T_GLOBAL_DEBUG_VIRTUAL > 0
-  #define T_VIRTUAL_CALL()                                              \
+#if T_GLOBAL_DEBUG_VIRTUAL > 1
+  #define T_VIRTUAL_CALL()                                                \
+    ::apache::thrift::profile_virtual_call(typeid(*this))
+  #define T_GENERIC_PROTOCOL(template_class, generic_prot, specific_prot) \
+    do {                                                                  \
+      if (!(specific_prot)) {                                             \
+        ::apache::thrift::profile_generic_protocol(                     \
+            typeid(*template_class), typeid(*generic_prot));              \
+      }                                                                   \
+    } while (0)
+#elif T_GLOBAL_DEBUG_VIRTUAL == 1
+  #define T_VIRTUAL_CALL()                                                \
     fprintf(stderr,"[%s,%d] virtual call\n", __FILE__, __LINE__)
+  #define T_GENERIC_PROTOCOL(template_class, generic_prot, specific_prot) \
+    do {                                                                  \
+      if (!(specific_prot)) {                                             \
+        fprintf(stderr,                                                   \
+                "[%s,%d] failed to cast to specific protocol type\n",     \
+                __FILE__, __LINE__);                                      \
+      }                                                                   \
+    } while (0)
 #else
   #define T_VIRTUAL_CALL()
+  #define T_GENERIC_PROTOCOL(template_class, generic_prot, specific_prot)
 #endif
 
 #endif // #ifndef _THRIFT_TLOGGING_H_
diff --git a/lib/cpp/src/Thrift.h b/lib/cpp/src/Thrift.h
index cb7d55a..a8bf2a8 100644
--- a/lib/cpp/src/Thrift.h
+++ b/lib/cpp/src/Thrift.h
@@ -36,6 +36,7 @@
 #include <set>
 #include <vector>
 #include <exception>
+#include <typeinfo>
 
 #include "TLogging.h"
 
@@ -134,6 +135,15 @@
   return new TExceptionWrapper<E>(e);
 }
 
+#if T_GLOBAL_DEBUG_VIRTUAL > 1
+void profile_virtual_call(const std::type_info& info);
+void profile_generic_protocol(const std::type_info& template_type,
+                              const std::type_info& prot_type);
+void profile_print_info(FILE *f);
+void profile_print_info();
+void profile_write_pprof(FILE* gen_calls_f, FILE* virtual_calls_f);
+#endif
+
 }} // apache::thrift
 
 #endif // #ifndef _THRIFT_THRIFT_H_
diff --git a/lib/cpp/src/VirtualProfiling.cpp b/lib/cpp/src/VirtualProfiling.cpp
new file mode 100644
index 0000000..0b023af
--- /dev/null
+++ b/lib/cpp/src/VirtualProfiling.cpp
@@ -0,0 +1,455 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include <Thrift.h>
+
+// Do nothing if virtual call profiling is not enabled
+#if T_GLOBAL_DEBUG_VIRTUAL > 1
+
+// TODO: This code only works with g++ (since we rely on the fact
+// that all std::type_info instances referring to a particular type
+// always return the exact same pointer value from name().)
+#ifndef __GNUG__
+#error "Thrift virtual function profiling currently only works with gcc"
+#endif // !__GNUG__
+
+// TODO: We also require glibc for the backtrace() and backtrace_symbols()
+// functions.
+#ifndef __GLIBC__
+#error "Thrift virtual function profiling currently requires glibc"
+#endif // !__GLIBC__
+
+
+#include <concurrency/Mutex.h>
+
+#include <ext/hash_map>
+#include <execinfo.h>
+#include <stdio.h>
+
+namespace apache { namespace thrift {
+
+using ::apache::thrift::concurrency::Mutex;
+using ::apache::thrift::concurrency::Guard;
+
+static const unsigned int MAX_STACK_DEPTH = 15;
+
+/**
+ * A stack trace
+ */
+class Backtrace {
+ public:
+  Backtrace(int skip = 0);
+  Backtrace(Backtrace const &bt);
+
+  void operator=(Backtrace const &bt) {
+    numCallers_ = bt.numCallers_;
+    if (numCallers_ >= 0) {
+      memcpy(callers_, bt.callers_, numCallers_ * sizeof(void*));
+    }
+  }
+
+  bool operator==(Backtrace const &bt) const {
+    return (cmp(bt) == 0);
+  }
+
+  size_t hash() const {
+    intptr_t ret = 0;
+    for (int n = 0; n < numCallers_; ++n) {
+      ret ^= reinterpret_cast<intptr_t>(callers_[n]);
+    }
+    return static_cast<size_t>(ret);
+  }
+
+  int cmp(Backtrace const& bt) const {
+    int depth_diff = (numCallers_ - bt.numCallers_);
+    if (depth_diff != 0) {
+      return depth_diff;
+    }
+
+    for (int n = 0; n < numCallers_; ++n) {
+      int diff = reinterpret_cast<intptr_t>(callers_[n]) -
+        reinterpret_cast<intptr_t>(bt.callers_[n]);
+      if (diff != 0) {
+        return diff;
+      }
+    }
+
+    return 0;
+  }
+
+  void print(FILE *f, int indent=0, int start=0) const {
+    char **strings = backtrace_symbols(callers_, numCallers_);
+    if (strings) {
+      start += skip_;
+      if (start < 0) {
+        start = 0;
+      }
+      for (int n = start; n < numCallers_; ++n) {
+        fprintf(f, "%*s#%-2d %s\n", indent, "", n, strings[n]);
+      }
+      free(strings);
+    } else {
+      fprintf(f, "%*s<failed to determine symbols>\n", indent, "");
+    }
+  }
+
+  int getDepth() const {
+    return numCallers_ - skip_;
+  }
+
+  void *getFrame(int index) const {
+    int adjusted_index = index + skip_;
+    if (adjusted_index < 0 || adjusted_index >= numCallers_) {
+      return NULL;
+    }
+    return callers_[adjusted_index];
+  }
+
+ private:
+  void *callers_[MAX_STACK_DEPTH];
+  int numCallers_;
+  int skip_;
+};
+
+// Define the constructors non-inline, so they consistently add a single
+// frame to the stack trace, regardless of whether optimization is enabled
+Backtrace::Backtrace(int skip)
+  : skip_(skip + 1) // ignore the constructor itself
+{
+  numCallers_ = backtrace(callers_, MAX_STACK_DEPTH);
+  if (skip_ > numCallers_) {
+    skip_ = numCallers_;
+  }
+}
+
+Backtrace::Backtrace(Backtrace const &bt)
+  : numCallers_(bt.numCallers_)
+  , skip_(bt.skip_) {
+  if (numCallers_ >= 0) {
+    memcpy(callers_, bt.callers_, numCallers_ * sizeof(void*));
+  }
+}
+
+/**
+ * A backtrace, plus one or two type names
+ */
+class Key {
+ public:
+  class Hash {
+   public:
+    size_t operator()(Key const& k) const {
+      return k.hash();
+    }
+  };
+
+  Key(const Backtrace* bt, const std::type_info& type_info)
+    : backtrace_(bt)
+    , typeName1_(type_info.name())
+    , typeName2_(NULL) {
+  }
+
+  Key(const Backtrace* bt, const std::type_info& type_info1,
+      const std::type_info& type_info2)
+    : backtrace_(bt)
+    , typeName1_(type_info1.name())
+    , typeName2_(type_info2.name()) {
+  }
+
+  Key(const Key& k)
+    : backtrace_(k.backtrace_)
+    , typeName1_(k.typeName1_)
+    , typeName2_(k.typeName2_) {
+  }
+
+  void operator=(const Key& k) {
+    backtrace_ = k.backtrace_;
+    typeName1_ = k.typeName1_;
+    typeName2_ = k.typeName2_;
+  }
+
+  const Backtrace* getBacktrace() const {
+    return backtrace_;
+  }
+
+  const char* getTypeName() const {
+    return typeName1_;
+  }
+
+  const char* getTypeName2() const {
+    return typeName2_;
+  }
+
+  void makePersistent() {
+    // Copy the Backtrace object
+    backtrace_ = new Backtrace(*backtrace_);
+
+    // NOTE: We don't copy the type name.
+    // The GNU libstdc++ implementation of type_info::name() returns a value
+    // that will be valid for the lifetime of the program.  (Although the C++
+    // standard doesn't guarantee this will be true on all implementations.)
+  }
+
+  /**
+   * Clean up memory allocated by makePersistent()
+   *
+   * Should only be invoked if makePersistent() has previously been called.
+   * The Key should no longer be used after cleanup() is called.
+   */
+  void cleanup() {
+    delete backtrace_;
+    backtrace_ = NULL;
+  }
+
+  int cmp(const Key& k) const {
+    int ret = backtrace_->cmp(*k.backtrace_);
+    if (ret != 0) {
+      return ret;
+    }
+
+    // NOTE: We compare just the name pointers.
+    // With GNU libstdc++, every type_info object for the same type points to
+    // exactly the same name string.  (Although this isn't guaranteed by the
+    // C++ standard.)
+    ret = k.typeName1_ - typeName1_;
+    if (ret != 0) {
+      return ret;
+    }
+    return k.typeName2_ - typeName2_;
+  }
+
+  bool operator==(const Key& k) const {
+    return cmp(k) == 0;
+  }
+
+  size_t hash() const {
+    // NOTE: As above, we just use the name pointer value.
+    // Works with GNU libstdc++, but not guaranteed to be correct on all
+    // implementations.
+    return backtrace_->hash() ^
+      reinterpret_cast<size_t>(typeName1_) ^
+      reinterpret_cast<size_t>(typeName2_);
+  }
+
+ private:
+  const Backtrace* backtrace_;
+  const char* typeName1_;
+  const char* typeName2_;
+};
+
+/**
+ * A functor that determines which of two BacktraceMap entries
+ * has a higher count.
+ */
+class CountGreater {
+ public:
+  bool operator()(std::pair<Key, size_t> bt1,
+                  std::pair<Key, size_t> bt2) const {
+    return bt1.second > bt2.second;
+  }
+};
+
+typedef __gnu_cxx::hash_map<Key, size_t, Key::Hash> BacktraceMap;
+
+/**
+ * A map describing how many times T_VIRTUAL_CALL() has been invoked.
+ */
+BacktraceMap virtual_calls;
+Mutex virtual_calls_mutex;
+
+/**
+ * A map describing how many times T_GENERIC_PROTOCOL() has been invoked.
+ */
+BacktraceMap generic_calls;
+Mutex generic_calls_mutex;
+
+
+void _record_backtrace(BacktraceMap* map, const Mutex& mutex, Key *k) {
+  Guard guard(mutex);
+
+  BacktraceMap::iterator it = map->find(*k);
+  if (it == map->end()) {
+    k->makePersistent();
+    map->insert(std::make_pair(*k, 1));
+  } else {
+    // increment the count
+    // NOTE: we could assert if it->second is 0 afterwards, since that would
+    // mean we've wrapped.
+    ++(it->second);
+  }
+}
+
+/**
+ * Record an unnecessary virtual function call.
+ *
+ * This method is invoked by the T_VIRTUAL_CALL() macro.
+ */
+void profile_virtual_call(const std::type_info& type) {
+  int const skip = 1; // ignore this frame
+  Backtrace bt(skip);
+  Key k(&bt, type);
+  _record_backtrace(&virtual_calls, virtual_calls_mutex, &k);
+}
+
+/**
+ * Record a call to a template processor with a protocol that is not the one
+ * specified in the template parameter.
+ *
+ * This method is invoked by the T_GENERIC_PROTOCOL() macro.
+ */
+void profile_generic_protocol(const std::type_info& template_type,
+                              const std::type_info& prot_type) {
+  int const skip = 1; // ignore this frame
+  Backtrace bt(skip);
+  Key k(&bt, template_type, prot_type);
+  _record_backtrace(&generic_calls, generic_calls_mutex, &k);
+}
+
+/**
+ * Print the recorded profiling information to the specified file.
+ */
+void profile_print_info(FILE* f) {
+  typedef std::vector< std::pair<Key, size_t> > BacktraceVector;
+
+  CountGreater is_greater;
+
+  // Grab both locks for the duration of the print operation,
+  // to ensure the output is a consistent snapshot of a single point in time
+  Guard generic_calls_guard(generic_calls_mutex);
+  Guard virtual_calls_guard(virtual_calls_mutex);
+
+  // print the info from generic_calls, sorted by frequency
+  //
+  // We print the generic_calls info ahead of virtual_calls, since it is more
+  // useful in some cases.  All T_GENERIC_PROTOCOL calls can be eliminated
+  // from most programs.  Not all T_VIRTUAL_CALLs will be eliminated by
+  // converting to templates.
+  BacktraceVector gp_sorted(generic_calls.begin(), generic_calls.end());
+  std::sort(gp_sorted.begin(), gp_sorted.end(), is_greater);
+
+  for (BacktraceVector::const_iterator it = gp_sorted.begin();
+       it != gp_sorted.end();
+       ++it) {
+    Key const &key = it->first;
+    size_t const count = it->second;
+    fprintf(f, "T_GENERIC_PROTOCOL: %zu calls to %s with a %s:\n",
+            count, key.getTypeName(), key.getTypeName2());
+    key.getBacktrace()->print(f, 2);
+    fprintf(f, "\n");
+  }
+
+  // print the info from virtual_calls, sorted by frequency
+  BacktraceVector vc_sorted(virtual_calls.begin(), virtual_calls.end());
+  std::sort(vc_sorted.begin(), vc_sorted.end(), is_greater);
+
+  for (BacktraceVector::const_iterator it = vc_sorted.begin();
+       it != vc_sorted.end();
+       ++it) {
+    Key const &key = it->first;
+    size_t const count = it->second;
+    fprintf(f, "T_VIRTUAL_CALL: %zu calls on %s:\n", count, key.getTypeName());
+    key.getBacktrace()->print(f, 2);
+    fprintf(f, "\n");
+  }
+}
+
+/**
+ * Print the recorded profiling information to stdout.
+ */
+void profile_print_info() {
+  profile_print_info(stdout);
+}
+
+/**
+ * Write a BacktraceMap as Google CPU profiler binary data.
+ */
+static void profile_write_pprof_file(FILE* f, BacktraceMap const& map) {
+  // Write the header
+  uintptr_t header[5] = { 0, 3, 0, 0, 0 };
+  fwrite(&header, sizeof(header), 1, f);
+
+  // Write the profile records
+  for (BacktraceMap::const_iterator it = map.begin(); it != map.end(); ++it) {
+    uintptr_t count = it->second;
+    fwrite(&count, sizeof(count), 1, f);
+
+    Backtrace const* bt = it->first.getBacktrace();
+    uintptr_t num_pcs = bt->getDepth();
+    fwrite(&num_pcs, sizeof(num_pcs), 1, f);
+
+    for (uintptr_t n = 0; n < num_pcs; ++n) {
+      void* pc = bt->getFrame(n);
+      fwrite(&pc, sizeof(pc), 1, f);
+    }
+  }
+
+  // Write the trailer
+  uintptr_t trailer[3] = { 0, 1, 0 };
+  fwrite(&trailer, sizeof(trailer), 1, f);
+
+  // Write /proc/self/maps
+  // TODO(simpkins): This only works on linux
+  FILE *proc_maps = fopen("/proc/self/maps", "r");
+  if (proc_maps) {
+    uint8_t buf[4096];
+    while (true) {
+      size_t bytes_read = fread(buf, 1, sizeof(buf), proc_maps);
+      if (bytes_read == 0) {
+        break;
+      }
+      fwrite(buf, 1, bytes_read, f);
+    }
+    fclose(proc_maps);
+  }
+}
+
+/**
+ * Write the recorded profiling information as pprof files.
+ *
+ * This writes the information using the Google CPU profiler binary data
+ * format, so it can be analyzed with pprof.  Note that information about the
+ * protocol/transport data types cannot be stored in this file format.
+ *
+ * See http://code.google.com/p/google-perftools/ for more details.
+ *
+ * @param gen_calls_f     The information about calls to
+ *                        profile_generic_protocol() will be written to this
+ *                        file.
+ * @param virtual_calls_f The information about calls to
+ *                        profile_virtual_call() will be written to this file.
+ */
+void profile_write_pprof(FILE* gen_calls_f, FILE* virtual_calls_f) {
+  typedef std::vector< std::pair<Key, size_t> > BacktraceVector;
+
+  CountGreater is_greater;
+
+  // Grab both locks for the duration of the print operation,
+  // to ensure the output is a consistent snapshot of a single point in time
+  Guard generic_calls_guard(generic_calls_mutex);
+  Guard virtual_calls_guard(virtual_calls_mutex);
+
+  // write the info from generic_calls
+  profile_write_pprof_file(gen_calls_f, generic_calls);
+
+  // write the info from virtual_calls
+  profile_write_pprof_file(virtual_calls_f, virtual_calls);
+}
+
+}} // apache::thrift
+
+#endif // T_GLOBAL_PROFILE_VIRTUAL > 0