[HICN-540] Optimizations for libhicntransport

Change-Id: I8b46b4eb2ef5488c09041887cc8296a216440f33
Signed-off-by: Mauro Sardara <msardara@cisco.com>

23 files changed, 341 insertions, 205 deletions

diff --git a/libtransport/includes/hicn/transport/core/content_object.h b/libtransport/includes/hicn/transport/core/content_object.h
index 5af548fe4..822790e56 100644
--- a/libtransport/includes/hicn/transport/core/content_object.h
+++ b/libtransport/includes/hicn/transport/core/content_object.h
@@ -46,8 +46,6 @@ class ContentObject : public Packet {
 
   ~ContentObject() override;
 
-  void replace(MemBufPtr &&buffer) override;
-
   const Name &getName() const override;
 
   Name &getWritableName() override;
diff --git a/libtransport/includes/hicn/transport/core/interest.h b/libtransport/includes/hicn/transport/core/interest.h
index f0c546a8e..c572afbff 100644
--- a/libtransport/includes/hicn/transport/core/interest.h
+++ b/libtransport/includes/hicn/transport/core/interest.h
@@ -44,8 +44,6 @@ class Interest
 
   ~Interest() override;
 
-  void replace(MemBufPtr &&buffer) override;
-
   const Name &getName() const override;
 
   Name &getWritableName() override;
diff --git a/libtransport/includes/hicn/transport/core/packet.h b/libtransport/includes/hicn/transport/core/packet.h
index e758aa13e..3ddc4a595 100644
--- a/libtransport/includes/hicn/transport/core/packet.h
+++ b/libtransport/includes/hicn/transport/core/packet.h
@@ -17,6 +17,7 @@
 
 #include <hicn/transport/core/name.h>
 #include <hicn/transport/core/payload_type.h>
+#include <hicn/transport/errors/malformed_packet_exception.h>
 #include <hicn/transport/portability/portability.h>
 #include <hicn/transport/security/crypto_hasher.h>
 #include <hicn/transport/security/crypto_suite.h>
@@ -81,7 +82,12 @@ class Packet : public std::enable_shared_from_this<Packet> {
   virtual ~Packet();
 
   static std::size_t getHeaderSizeFromFormat(Format format,
-                                             std::size_t signature_size = 0);
+                                             std::size_t signature_size = 0) {
+    std::size_t header_length;
+    hicn_packet_get_header_length_from_format(format, &header_length);
+    int is_ah = _is_ah(format);
+    return is_ah * (header_length + signature_size) + (!is_ah) * header_length;
+  }
 
   static std::size_t getHeaderSizeFromBuffer(Format format,
                                              const uint8_t *buffer);
@@ -91,9 +97,26 @@ class Packet : public std::enable_shared_from_this<Packet> {
 
   static bool isInterest(const uint8_t *buffer);
 
-  static Format getFormatFromBuffer(const uint8_t *buffer);
+  static Format getFormatFromBuffer(const uint8_t *buffer) {
+    Format format = HF_UNSPEC;
 
-  virtual void replace(MemBufPtr &&buffer);
+    if (TRANSPORT_EXPECT_FALSE(
+            hicn_packet_get_format((const hicn_header_t *)buffer, &format) <
+            0)) {
+      throw errors::MalformedPacketException();
+    }
+
+    return format;
+  }
+
+  TRANSPORT_ALWAYS_INLINE void replace(MemBufPtr &&buffer) {
+    packet_ = std::move(buffer);
+    packet_start_ = reinterpret_cast<hicn_header_t *>(packet_->writableData());
+    header_head_ = packet_.get();
+    payload_head_ = nullptr;
+    format_ = getFormatFromBuffer(reinterpret_cast<uint8_t *>(packet_start_));
+    name_.clear();
+  }
 
   std::size_t payloadSize() const;
 
@@ -123,6 +146,19 @@ class Packet : public std::enable_shared_from_this<Packet> {
 
   std::unique_ptr<utils::MemBuf> getPayload() const;
 
+  std::pair<const uint8_t *, std::size_t> getPayloadReference() const {
+    int signature_size = 0;
+    if (_is_ah(format_)) {
+      signature_size = (uint32_t)getSignatureSize();
+    }
+
+    auto header_size = getHeaderSizeFromFormat(format_, signature_size);
+    auto payload_length = packet_->length() - header_size;
+
+    return std::make_pair(packet_->data() + header_size,
+                          payload_length);
+  }
+
   Packet &updateLength(std::size_t length = 0);
 
   PayloadType getPayloadType() const;
@@ -152,7 +188,21 @@ class Packet : public std::enable_shared_from_this<Packet> {
   virtual utils::CryptoHash computeDigest(
       utils::CryptoHashType algorithm) const;
 
-  void setChecksum();
+  void setChecksum() {
+    uint16_t partial_csum = 0;
+
+    for (utils::MemBuf *current = header_head_->next();
+         current && current != header_head_; current = current->next()) {
+      if (partial_csum != 0) {
+        partial_csum = ~partial_csum;
+      }
+      partial_csum = csum(current->data(), current->length(), partial_csum);
+    }
+    if (hicn_packet_compute_header_checksum(format_, packet_start_,
+                                            partial_csum) < 0) {
+      throw errors::MalformedPacketException();
+    }
+  }
 
   bool checkIntegrity() const;
 
@@ -184,7 +234,19 @@ class Packet : public std::enable_shared_from_this<Packet> {
  private:
   virtual void resetForHash() = 0;
   void setSignatureSize(std::size_t size_bytes);
-  std::size_t getSignatureSize() const;
+
+  std::size_t getSignatureSize() const {
+    size_t size_bytes;
+    int ret =
+        hicn_packet_get_signature_size(format_, packet_start_, &size_bytes);
+
+    if (ret < 0) {
+      throw errors::RuntimeException("Packet without Authentication Header.");
+    }
+
+    return size_bytes;
+  }
+
   uint8_t *getSignature() const;
   void separateHeaderPayload();
 
diff --git a/libtransport/includes/hicn/transport/utils/CMakeLists.txt b/libtransport/includes/hicn/transport/utils/CMakeLists.txt
index 396bd06d6..38ecc3d37 100644
--- a/libtransport/includes/hicn/transport/utils/CMakeLists.txt
+++ b/libtransport/includes/hicn/transport/utils/CMakeLists.txt
@@ -28,6 +28,7 @@ list(APPEND HEADER_FILES
   ${CMAKE_CURRENT_SOURCE_DIR}/object_pool.h
   ${CMAKE_CURRENT_SOURCE_DIR}/membuf.h
   ${CMAKE_CURRENT_SOURCE_DIR}/spinlock.h
+  ${CMAKE_CURRENT_SOURCE_DIR}/fixed_block_allocator.h
 )
 
 if(NOT WIN32)
diff --git a/libtransport/includes/hicn/transport/utils/fixed_block_allocator.h b/libtransport/includes/hicn/transport/utils/fixed_block_allocator.h
new file mode 100644
index 000000000..1ade1516e
--- /dev/null
+++ b/libtransport/includes/hicn/transport/utils/fixed_block_allocator.h
@@ -0,0 +1,136 @@
+/*
+ * Copyright (c) 2019 Cisco and/or its affiliates.
+ */
+
+#pragma once
+
+#include <hicn/transport/portability/c_portability.h>
+#include <hicn/transport/utils/spinlock.h>
+
+#include <stdint.h>
+#include <cstdlib>
+#include <memory>
+#include <cassert>
+
+namespace utils {
+template <std::size_t DEFAULT_SIZE = 512, std::size_t OBJECTS = 4096>
+class FixedBlockAllocator {
+  FixedBlockAllocator(std::size_t size = DEFAULT_SIZE,
+                      std::size_t objects = OBJECTS)
+      : block_size_(size < sizeof(void*) ? sizeof(long*) : size),
+        object_size_(size),
+        max_objects_(objects),
+        p_head_(NULL),
+        pool_index_(0),
+        block_count_(0),
+        blocks_in_use_(0),
+        allocations_(0),
+        deallocations_(0) {
+    p_pool_ = (uint8_t*)new uint8_t[block_size_ * max_objects_];
+  }
+
+ public:
+  static FixedBlockAllocator* getInstance() {
+    if (!instance_) {
+      instance_ = std::unique_ptr<FixedBlockAllocator>(
+          new FixedBlockAllocator(DEFAULT_SIZE, OBJECTS));
+    }
+
+    return instance_.get();
+  }
+
+  ~FixedBlockAllocator() { delete[] p_pool_; }
+
+  TRANSPORT_ALWAYS_INLINE void* allocateBlock(size_t size = DEFAULT_SIZE) {
+    assert(size <= DEFAULT_SIZE);
+    uint32_t index;
+
+    void* p_block = pop();
+    if (!p_block) {
+      if (pool_index_ < max_objects_) {
+        {
+          SpinLock::Acquire locked(lock_);
+          index = pool_index_++;
+        }
+        p_block = (void*)(p_pool_ + (index * block_size_));
+      } else {
+        // TODO Consider increasing pool here instead of throwing an exception
+        throw std::runtime_error("No more memory available from packet pool!");
+      }
+    }
+
+    blocks_in_use_++;
+    allocations_++;
+
+    return p_block;
+  }
+
+  TRANSPORT_ALWAYS_INLINE void deallocateBlock(void* pBlock) {
+    push(pBlock);
+    {
+      SpinLock::Acquire locked(lock_);
+      blocks_in_use_--;
+      deallocations_++;
+    }
+  }
+
+  TRANSPORT_ALWAYS_INLINE std::size_t blockSize() { return block_size_; }
+
+  TRANSPORT_ALWAYS_INLINE uint32_t blockCount() { return block_count_; }
+
+  TRANSPORT_ALWAYS_INLINE uint32_t blocksInUse() { return blocks_in_use_; }
+
+  TRANSPORT_ALWAYS_INLINE uint32_t allocations() { return allocations_; }
+
+  TRANSPORT_ALWAYS_INLINE uint32_t deallocations() { return deallocations_; }
+
+ private:
+  TRANSPORT_ALWAYS_INLINE void push(void* p_memory) {
+    Block* p_block = (Block*)p_memory;
+    {
+      SpinLock::Acquire locked(lock_);
+      p_block->p_next = p_head_;
+      p_head_ = p_block;
+    }
+  }
+
+  TRANSPORT_ALWAYS_INLINE void* pop() {
+    Block* p_block = nullptr;
+
+    {
+      SpinLock::Acquire locked(lock_);
+      if (p_head_) {
+        p_block = p_head_;
+        p_head_ = p_head_->p_next;
+      }
+    }
+
+    return (void*)p_block;
+  }
+
+  struct Block {
+    Block* p_next;
+  };
+
+  static std::unique_ptr<FixedBlockAllocator> instance_;
+
+  const std::size_t block_size_;
+  const std::size_t object_size_;
+  const std::size_t max_objects_;
+
+  Block* p_head_;
+  uint8_t* p_pool_;
+  uint32_t pool_index_;
+  uint32_t block_count_;
+  uint32_t blocks_in_use_;
+  uint32_t allocations_;
+  uint32_t deallocations_;
+
+  SpinLock lock_;
+};
+
+template <std::size_t A, std::size_t B>
+std::unique_ptr<FixedBlockAllocator<A, B>>
+    FixedBlockAllocator<A, B>::instance_ = nullptr;
+
+}  // namespace utils
\ No newline at end of file
diff --git a/libtransport/src/core/CMakeLists.txt b/libtransport/src/core/CMakeLists.txt
index 12ef9cfe4..5c8ab9270 100644
--- a/libtransport/src/core/CMakeLists.txt
+++ b/libtransport/src/core/CMakeLists.txt
@@ -33,7 +33,6 @@ list(APPEND HEADER_FILES
 list(APPEND SOURCE_FILES
   ${CMAKE_CURRENT_SOURCE_DIR}/content_object.cc
   ${CMAKE_CURRENT_SOURCE_DIR}/interest.cc
-  ${CMAKE_CURRENT_SOURCE_DIR}/pending_interest.cc
   ${CMAKE_CURRENT_SOURCE_DIR}/packet.cc
   ${CMAKE_CURRENT_SOURCE_DIR}/name.cc
   ${CMAKE_CURRENT_SOURCE_DIR}/prefix.cc
diff --git a/libtransport/src/core/content_object.cc b/libtransport/src/core/content_object.cc
index 6cbcdb29e..f5cccf404 100644
--- a/libtransport/src/core/content_object.cc
+++ b/libtransport/src/core/content_object.cc
@@ -86,15 +86,6 @@ ContentObject::ContentObject(ContentObject &&other) : Packet(std::move(other)) {
 
 ContentObject::~ContentObject() {}
 
-void ContentObject::replace(MemBufPtr &&buffer) {
-  Packet::replace(std::move(buffer));
-
-  if (hicn_data_get_name(format_, packet_start_, name_.getStructReference()) <
-      0) {
-    throw errors::RuntimeException("Error getting name from content object.");
-  }
-}
-
 const Name &ContentObject::getName() const {
   if (!name_) {
     if (hicn_data_get_name(format_, packet_start_,
diff --git a/libtransport/src/core/forwarder_interface.h b/libtransport/src/core/forwarder_interface.h
index 3e70e221d..3b016c4bb 100644
--- a/libtransport/src/core/forwarder_interface.h
+++ b/libtransport/src/core/forwarder_interface.h
@@ -95,15 +95,11 @@ class ForwarderInterface {
       packet.setLocator(inet6_address_);
     }
 
-    // TRANSPORT_LOGI("Sending packet %s at %lu",
-    // packet.getName().toString().c_str(),
-    // utils::SteadyClock::now().time_since_epoch().count());
     packet.setChecksum();
     connector_.send(packet.acquireMemBufReference());
   }
 
   TRANSPORT_ALWAYS_INLINE void send(const uint8_t *packet, std::size_t len) {
-    // ASIO_COMPLETION_HANDLER_CHECK(Handler, packet_sent) type_check;
     counters_.tx_packets++;
     counters_.tx_bytes += len;
 
diff --git a/libtransport/src/core/interest.cc b/libtransport/src/core/interest.cc
index 166632f0a..9ee662615 100644
--- a/libtransport/src/core/interest.cc
+++ b/libtransport/src/core/interest.cc
@@ -72,15 +72,6 @@ Interest::Interest(Interest &&other_interest)
 
 Interest::~Interest() {}
 
-void Interest::replace(MemBufPtr &&buffer) {
-  Packet::replace(std::move(buffer));
-
-  if (hicn_interest_get_name(format_, packet_start_,
-                             name_.getStructReference()) < 0) {
-    throw errors::MalformedPacketException();
-  }
-}
-
 const Name &Interest::getName() const {
   if (!name_) {
     if (hicn_interest_get_name(format_, packet_start_,
diff --git a/libtransport/src/core/memif_connector.cc b/libtransport/src/core/memif_connector.cc
index 2292e9b41..179db63e4 100644
--- a/libtransport/src/core/memif_connector.cc
+++ b/libtransport/src/core/memif_connector.cc
@@ -353,7 +353,7 @@ int MemifConnector::onInterrupt(memif_conn_handle_t conn, void *private_ctx,
 
     c->rx_buf_num += rx;
 
-    if (TRANSPORT_EXPECT_TRUE(connector->io_service_.stopped())) {
+    if (TRANSPORT_EXPECT_FALSE(connector->io_service_.stopped())) {
       TRANSPORT_LOGE("socket stopped: ignoring %u packets", rx);
       goto error;
     }
diff --git a/libtransport/src/core/packet.cc b/libtransport/src/core/packet.cc
index 67e647fca..6815868f0 100644
--- a/libtransport/src/core/packet.cc
+++ b/libtransport/src/core/packet.cc
@@ -69,14 +69,6 @@ Packet::Packet(Packet &&other)
 
 Packet::~Packet() {}
 
-std::size_t Packet::getHeaderSizeFromFormat(Format format,
-                                            size_t signature_size) {
-  std::size_t header_length;
-  hicn_packet_get_header_length_from_format(format, &header_length);
-  int is_ah = _is_ah(format);
-  return is_ah * (header_length + signature_size) + (!is_ah) * header_length;
-}
-
 std::size_t Packet::getHeaderSizeFromBuffer(Format format,
                                             const uint8_t *buffer) {
   size_t header_length;
@@ -99,17 +91,6 @@ bool Packet::isInterest(const uint8_t *buffer) {
   return !is_interest;
 }
 
-Packet::Format Packet::getFormatFromBuffer(const uint8_t *buffer) {
-  Format format = HF_UNSPEC;
-
-  if (TRANSPORT_EXPECT_FALSE(
-          hicn_packet_get_format((const hicn_header_t *)buffer, &format) < 0)) {
-    throw errors::MalformedPacketException();
-  }
-
-  return format;
-}
-
 std::size_t Packet::getPayloadSizeFromBuffer(Format format,
                                              const uint8_t *buffer) {
   std::size_t payload_length;
@@ -122,14 +103,6 @@ std::size_t Packet::getPayloadSizeFromBuffer(Format format,
   return payload_length;
 }
 
-void Packet::replace(MemBufPtr &&buffer) {
-  packet_ = std::move(buffer);
-  packet_start_ = reinterpret_cast<hicn_header_t *>(packet_->writableData());
-  header_head_ = packet_.get();
-  payload_head_ = nullptr;
-  format_ = getFormatFromBuffer(reinterpret_cast<uint8_t *>(packet_start_));
-}
-
 std::size_t Packet::payloadSize() const {
   return getPayloadSizeFromBuffer(format_,
                                   reinterpret_cast<uint8_t *>(packet_start_));
@@ -270,17 +243,6 @@ uint8_t *Packet::getSignature() const {
   return signature;
 }
 
-std::size_t Packet::getSignatureSize() const {
-  size_t size_bytes;
-  int ret = hicn_packet_get_signature_size(format_, packet_start_, &size_bytes);
-
-  if (ret < 0) {
-    throw errors::RuntimeException("Packet without Authentication Header.");
-  }
-
-  return size_bytes;
-}
-
 void Packet::setSignatureTimestamp(const uint64_t &timestamp) {
   int ret =
       hicn_packet_set_signature_timestamp(format_, packet_start_, timestamp);
@@ -366,22 +328,6 @@ utils::CryptoHash Packet::computeDigest(utils::CryptoHashType algorithm) const {
   return hasher.finalize();
 }
 
-void Packet::setChecksum() {
-  uint16_t partial_csum = 0;
-
-  for (utils::MemBuf *current = header_head_->next();
-       current && current != header_head_; current = current->next()) {
-    if (partial_csum != 0) {
-      partial_csum = ~partial_csum;
-    }
-    partial_csum = csum(current->data(), current->length(), partial_csum);
-  }
-  if (hicn_packet_compute_header_checksum(format_, packet_start_,
-                                          partial_csum) < 0) {
-    throw errors::MalformedPacketException();
-  }
-}
-
 bool Packet::checkIntegrity() const {
   if (hicn_packet_check_integrity(format_, packet_start_) < 0) {
     return false;
diff --git a/libtransport/src/core/pending_interest.h b/libtransport/src/core/pending_interest.h
index d9ec2ed40..aeff78ea2 100644
--- a/libtransport/src/core/pending_interest.h
+++ b/libtransport/src/core/pending_interest.h
@@ -47,17 +47,29 @@ class PendingInterest {
 
  public:
   using Ptr = utils::ObjectPool<PendingInterest>::Ptr;
-  PendingInterest();
+  PendingInterest()
+      : interest_(nullptr, nullptr),
+        timer_(),
+        on_content_object_callback_(),
+        on_interest_timeout_callback_() {}
 
   PendingInterest(Interest::Ptr &&interest,
-                  std::unique_ptr<asio::steady_timer> &&timer);
+                  std::unique_ptr<asio::steady_timer> &&timer)
+      : interest_(std::move(interest)),
+        timer_(std::move(timer)),
+        on_content_object_callback_(),
+        on_interest_timeout_callback_() {}
 
   PendingInterest(Interest::Ptr &&interest,
                   OnContentObjectCallback &&on_content_object,
                   OnInterestTimeoutCallback &&on_interest_timeout,
-                  std::unique_ptr<asio::steady_timer> &&timer);
+                  std::unique_ptr<asio::steady_timer> &&timer)
+      : interest_(std::move(interest)),
+        timer_(std::move(timer)),
+        on_content_object_callback_(std::move(on_content_object)),
+        on_interest_timeout_callback_(std::move(on_interest_timeout)) {}
 
-  ~PendingInterest();
+  ~PendingInterest() = default;
 
   template <typename Handler>
   TRANSPORT_ALWAYS_INLINE void startCountdown(Handler &&cb) {
@@ -66,19 +78,35 @@ class PendingInterest {
     timer_->async_wait(std::forward<Handler &&>(cb));
   }
 
-  void cancelTimer();
+  TRANSPORT_ALWAYS_INLINE void cancelTimer() { timer_->cancel(); }
 
-  Interest::Ptr &&getInterest();
+  TRANSPORT_ALWAYS_INLINE Interest::Ptr &&getInterest() {
+    return std::move(interest_);
+  }
 
-  void setInterest(Interest::Ptr &&interest);
+  TRANSPORT_ALWAYS_INLINE void setInterest(Interest::Ptr &&interest) {
+    interest_ = std::move(interest);
+  }
 
-  const OnContentObjectCallback &getOnDataCallback() const;
+  TRANSPORT_ALWAYS_INLINE const OnContentObjectCallback &getOnDataCallback()
+      const {
+    return on_content_object_callback_;
+  }
 
-  void setOnContentObjectCallback(OnContentObjectCallback &&on_content_object);
+  TRANSPORT_ALWAYS_INLINE void setOnContentObjectCallback(
+      OnContentObjectCallback &&on_content_object) {
+    PendingInterest::on_content_object_callback_ = on_content_object;
+  }
 
-  const OnInterestTimeoutCallback &getOnTimeoutCallback() const;
+  TRANSPORT_ALWAYS_INLINE const OnInterestTimeoutCallback &
+  getOnTimeoutCallback() const {
+    return on_interest_timeout_callback_;
+  }
 
-  void setOnTimeoutCallback(OnInterestTimeoutCallback &&on_interest_timeout);
+  TRANSPORT_ALWAYS_INLINE void setOnTimeoutCallback(
+      OnInterestTimeoutCallback &&on_interest_timeout) {
+    PendingInterest::on_interest_timeout_callback_ = on_interest_timeout;
+  }
 
  private:
   Interest::Ptr interest_;
diff --git a/libtransport/src/core/portal.h b/libtransport/src/core/portal.h
index cf1010068..34dfbd826 100644
--- a/libtransport/src/core/portal.h
+++ b/libtransport/src/core/portal.h
@@ -627,6 +627,8 @@ class Portal {
   }
 
  private:
+  portal_details::HandlerMemory async_callback_memory_;
+
   asio::io_service &io_service_;
   asio::io_service internal_io_service_;
   portal_details::Pool packet_pool_;
@@ -639,8 +641,6 @@ class Portal {
   ConsumerCallback *consumer_callback_;
   ProducerCallback *producer_callback_;
 
-  portal_details::HandlerMemory async_callback_memory_;
-
   typename ForwarderInt::ConnectorType connector_;
   ForwarderInt forwarder_interface_;
 };
diff --git a/libtransport/src/implementation/socket_consumer.h b/libtransport/src/implementation/socket_consumer.h
index 2fc8d2b48..488f238ba 100644
--- a/libtransport/src/implementation/socket_consumer.h
+++ b/libtransport/src/implementation/socket_consumer.h
@@ -35,7 +35,7 @@ class ConsumerSocket : public Socket<BasePortal> {
  public:
   ConsumerSocket(interface::ConsumerSocket *consumer, int protocol)
       : consumer_interface_(consumer),
-        portal_(std::make_shared<Portal>(io_service_)),
+        portal_(std::make_shared<Portal>()),
         async_downloader_(),
         interest_lifetime_(default_values::interest_lifetime),
         min_window_size_(default_values::min_window_size),
@@ -62,10 +62,8 @@ class ConsumerSocket : public Socket<BasePortal> {
         on_interest_satisfied_(VOID_HANDLER),
         on_content_object_input_(VOID_HANDLER),
         on_content_object_verification_(VOID_HANDLER),
-        on_content_object_(VOID_HANDLER),
         stats_summary_(VOID_HANDLER),
         read_callback_(nullptr),
-        virtual_download_(false),
         timer_interval_milliseconds_(0),
         guard_raaqm_params_() {
     switch (protocol) {
@@ -323,11 +321,6 @@ class ConsumerSocket : public Socket<BasePortal> {
     int result = SOCKET_OPTION_NOT_SET;
     if (!transport_protocol_->isRunning()) {
       switch (socket_option_key) {
-        case OtherOptions::VIRTUAL_DOWNLOAD:
-          virtual_download_ = socket_option_value;
-          result = SOCKET_OPTION_SET;
-          break;
-
         case GeneralTransportOptions::VERIFY_SIGNATURE:
           verify_signature_ = socket_option_value;
           result = SOCKET_OPTION_SET;
@@ -631,10 +624,6 @@ class ConsumerSocket : public Socket<BasePortal> {
         socket_option_value = transport_protocol_->isRunning();
         break;
 
-      case OtherOptions::VIRTUAL_DOWNLOAD:
-        socket_option_value = virtual_download_;
-        break;
-
       case GeneralTransportOptions::VERIFY_SIGNATURE:
         socket_option_value = verify_signature_;
         break;
@@ -861,8 +850,9 @@ class ConsumerSocket : public Socket<BasePortal> {
       /* Condition variable for the wait */
       std::condition_variable cv;
       bool done = false;
-      io_service_.dispatch([&socket_option_key, &socket_option_value, &mtx, &cv,
-                            &result, &done, &func]() {
+      portal_->getIoService().dispatch([&socket_option_key,
+                                        &socket_option_value, &mtx, &cv,
+                                        &result, &done, &func]() {
         std::unique_lock<std::mutex> lck(mtx);
         done = true;
         result = func(socket_option_key, socket_option_value);
@@ -881,7 +871,6 @@ class ConsumerSocket : public Socket<BasePortal> {
 
  protected:
   interface::ConsumerSocket *consumer_interface_;
-  asio::io_service io_service_;
 
   std::shared_ptr<Portal> portal_;
   utils::EventThread async_downloader_;
@@ -925,15 +914,11 @@ class ConsumerSocket : public Socket<BasePortal> {
   ConsumerInterestCallback on_interest_satisfied_;
   ConsumerContentObjectCallback on_content_object_input_;
   ConsumerContentObjectVerificationCallback on_content_object_verification_;
-  ConsumerContentObjectCallback on_content_object_;
   ConsumerTimerCallback stats_summary_;
   ConsumerContentObjectVerificationFailedCallback verification_failed_callback_;
 
   ReadCallback *read_callback_;
 
-  // Virtual download for traffic generator
-  bool virtual_download_;
-
   uint32_t timer_interval_milliseconds_;
 
   // Transport protocol
diff --git a/libtransport/src/protocols/byte_stream_reassembly.cc b/libtransport/src/protocols/byte_stream_reassembly.cc
index c2996ebc1..e15498bb1 100644
--- a/libtransport/src/protocols/byte_stream_reassembly.cc
+++ b/libtransport/src/protocols/byte_stream_reassembly.cc
@@ -80,19 +80,19 @@ void ByteStreamReassembly::assembleContent() {
 }
 
 void ByteStreamReassembly::copyContent(const ContentObject &content_object) {
-  auto a = content_object.getPayload();
-  auto payload_length = a->length();
+  auto payload = content_object.getPayloadReference();
+  auto payload_length = payload.second;
   auto write_size = std::min(payload_length, read_buffer_->tailroom());
   auto additional_bytes = payload_length > read_buffer_->tailroom()
                               ? payload_length - read_buffer_->tailroom()
                               : 0;
 
-  std::memcpy(read_buffer_->writableTail(), a->data(), write_size);
+  std::memcpy(read_buffer_->writableTail(), payload.first, write_size);
   read_buffer_->append(write_size);
 
   if (!read_buffer_->tailroom()) {
     notifyApplication();
-    std::memcpy(read_buffer_->writableTail(), a->data() + write_size,
+    std::memcpy(read_buffer_->writableTail(), payload.first + write_size,
                 additional_bytes);
     read_buffer_->append(additional_bytes);
   }
diff --git a/libtransport/src/protocols/protocol.cc b/libtransport/src/protocols/protocol.cc
index aa290bef8..8463f84f9 100644
--- a/libtransport/src/protocols/protocol.cc
+++ b/libtransport/src/protocols/protocol.cc
@@ -31,7 +31,16 @@ TransportProtocol::TransportProtocol(implementation::ConsumerSocket *icn_socket,
       index_manager_(
           std::make_unique<IndexManager>(socket_, this, reassembly_protocol)),
       is_running_(false),
-      is_first_(false) {
+      is_first_(false),
+      on_interest_retransmission_(VOID_HANDLER),
+      on_interest_output_(VOID_HANDLER),
+      on_interest_timeout_(VOID_HANDLER),
+      on_interest_satisfied_(VOID_HANDLER),
+      on_content_object_input_(VOID_HANDLER),
+      on_content_object_verification_(VOID_HANDLER),
+      stats_summary_(VOID_HANDLER),
+      verification_failed_callback_(VOID_HANDLER),
+      on_payload_(VOID_HANDLER) {
   socket_->getSocketOption(GeneralTransportOptions::PORTAL, portal_);
   socket_->getSocketOption(OtherOptions::STATISTICS, &stats_);
 }
@@ -46,6 +55,26 @@ int TransportProtocol::start() {
   // Set it is the first time we schedule an interest
   is_first_ = true;
 
+  // Get all callbacks references before starting
+  socket_->getSocketOption(ConsumerCallbacksOptions::INTEREST_RETRANSMISSION,
+                           &on_interest_retransmission_);
+  socket_->getSocketOption(ConsumerCallbacksOptions::INTEREST_OUTPUT,
+                           &on_interest_output_);
+  socket_->getSocketOption(ConsumerCallbacksOptions::INTEREST_EXPIRED,
+                           &on_interest_timeout_);
+  socket_->getSocketOption(ConsumerCallbacksOptions::INTEREST_SATISFIED,
+                           &on_interest_satisfied_);
+  socket_->getSocketOption(ConsumerCallbacksOptions::CONTENT_OBJECT_INPUT,
+                           &on_content_object_input_);
+  socket_->getSocketOption(ConsumerCallbacksOptions::CONTENT_OBJECT_TO_VERIFY,
+                           &on_content_object_verification_);
+  socket_->getSocketOption(ConsumerCallbacksOptions::STATS_SUMMARY,
+                           &stats_summary_);
+  socket_->getSocketOption(ConsumerCallbacksOptions::VERIFICATION_FAILED,
+                           &verification_failed_callback_);
+  socket_->getSocketOption(ConsumerCallbacksOptions::READ_CALLBACK,
+                           &on_payload_);
+
   // Schedule next interests
   scheduleNextInterests();
 
@@ -81,10 +110,7 @@ void TransportProtocol::resume() {
 }
 
 void TransportProtocol::onContentReassembled(std::error_code ec) {
-  interface::ConsumerSocket::ReadCallback *on_payload = VOID_HANDLER;
-  socket_->getSocketOption(READ_CALLBACK, &on_payload);
-
-  if (!on_payload) {
+  if (!on_payload_) {
     throw errors::RuntimeException(
         "The read callback must be installed in the transport before "
         "starting "
@@ -92,9 +118,9 @@ void TransportProtocol::onContentReassembled(std::error_code ec) {
   }
 
   if (!ec) {
-    on_payload->readSuccess(stats_->getBytesRecv());
+    on_payload_->readSuccess(stats_->getBytesRecv());
   } else {
-    on_payload->readError(ec);
+    on_payload_->readError(ec);
   }
 
   stop();
diff --git a/libtransport/src/protocols/protocol.h b/libtransport/src/protocols/protocol.h
index 949380959..db4524133 100644
--- a/libtransport/src/protocols/protocol.h
+++ b/libtransport/src/protocols/protocol.h
@@ -17,6 +17,8 @@
 
 #include <atomic>
 
+#include <hicn/transport/interfaces/callbacks.h>
+#include <hicn/transport/interfaces/socket_consumer.h>
 #include <hicn/transport/interfaces/statistics.h>
 #include <hicn/transport/utils/object_pool.h>
 
@@ -34,6 +36,8 @@ using namespace core;
 
 class IndexVerificationManager;
 
+using ReadCallback = interface::ConsumerSocket::ReadCallback;
+
 class TransportProtocolCallback {
   virtual void onContentObject(const core::Interest &interest,
                                const core::ContentObject &content_object) = 0;
@@ -89,6 +93,20 @@ class TransportProtocol : public implementation::BasePortal::ConsumerCallback,
   // True if it si the first time we schedule an interest
   std::atomic<bool> is_first_;
   interface::TransportStatistics *stats_;
+
+  // Callbacks
+  interface::ConsumerInterestCallback *on_interest_retransmission_;
+  interface::ConsumerInterestCallback *on_interest_output_;
+  interface::ConsumerInterestCallback *on_interest_timeout_;
+  interface::ConsumerInterestCallback *on_interest_satisfied_;
+  interface::ConsumerContentObjectCallback *on_content_object_input_;
+  interface::ConsumerContentObjectVerificationCallback
+      *on_content_object_verification_;
+  interface::ConsumerContentObjectCallback *on_content_object_;
+  interface::ConsumerTimerCallback *stats_summary_;
+  interface::ConsumerContentObjectVerificationFailedCallback
+      *verification_failed_callback_;
+  ReadCallback *on_payload_;
 };
 
 }  // end namespace protocol
diff --git a/libtransport/src/protocols/raaqm.cc b/libtransport/src/protocols/raaqm.cc
index 8a38f8ccf..0a93dec44 100644
--- a/libtransport/src/protocols/raaqm.cc
+++ b/libtransport/src/protocols/raaqm.cc
@@ -325,18 +325,12 @@ void RaaqmTransportProtocol::onContentObject(
   }
 
   // Call application-defined callbacks
-  ConsumerContentObjectCallback *callback_content_object = VOID_HANDLER;
-  socket_->getSocketOption(ConsumerCallbacksOptions::CONTENT_OBJECT_INPUT,
-                           &callback_content_object);
-  if (*callback_content_object) {
-    (*callback_content_object)(*socket_->getInterface(), *content_object);
+  if (*on_content_object_input_) {
+    (*on_content_object_input_)(*socket_->getInterface(), *content_object);
   }
 
-  ConsumerInterestCallback *callback_interest = VOID_HANDLER;
-  socket_->getSocketOption(ConsumerCallbacksOptions::INTEREST_SATISFIED,
-                           &callback_interest);
-  if (*callback_interest) {
-    (*callback_interest)(*socket_->getInterface(), *interest);
+  if (*on_interest_satisfied_) {
+    (*on_interest_satisfied_)(*socket_->getInterface(), *interest);
   }
 
   if (content_object->getPayloadType() == PayloadType::CONTENT_OBJECT) {
@@ -369,23 +363,17 @@ void RaaqmTransportProtocol::onPacketDropped(
   socket_->getSocketOption(GeneralTransportOptions::MAX_INTEREST_RETX, max_rtx);
 
   uint64_t segment = interest->getName().getSuffix();
-  ConsumerInterestCallback *callback = VOID_HANDLER;
+
   if (TRANSPORT_EXPECT_TRUE(interest_retransmissions_[segment & mask] <
                             max_rtx)) {
     stats_->updateRetxCount(1);
 
-    callback = VOID_HANDLER;
-    socket_->getSocketOption(ConsumerCallbacksOptions::INTEREST_RETRANSMISSION,
-                             &callback);
-    if (*callback) {
-      (*callback)(*socket_->getInterface(), *interest);
+    if (*on_interest_retransmission_) {
+      (*on_interest_retransmission_)(*socket_->getInterface(), *interest);
     }
 
-    callback = VOID_HANDLER;
-    socket_->getSocketOption(ConsumerCallbacksOptions::INTEREST_OUTPUT,
-                             &callback);
-    if (*callback) {
-      (*callback)(*socket_->getInterface(), *interest);
+    if (*on_interest_output_) {
+      (*on_interest_output_)(*socket_->getInterface(), *interest);
     }
 
     if (!is_running_) {
@@ -393,7 +381,6 @@ void RaaqmTransportProtocol::onPacketDropped(
     }
 
     interest_retransmissions_[segment & mask]++;
-
     interest_to_retransmit_.push(std::move(interest));
   } else {
     TRANSPORT_LOGE(
@@ -428,11 +415,8 @@ void RaaqmTransportProtocol::onTimeout(Interest::Ptr &&interest) {
     return;
   }
 
-  ConsumerInterestCallback *callback = VOID_HANDLER;
-  socket_->getSocketOption(ConsumerCallbacksOptions::INTEREST_EXPIRED,
-                           &callback);
-  if (*callback) {
-    (*callback)(*socket_->getInterface(), *interest);
+  if (*on_interest_timeout_) {
+    (*on_interest_timeout_)(*socket_->getInterface(), *interest);
   }
 
   afterDataUnsatisfied(segment);
@@ -444,18 +428,12 @@ void RaaqmTransportProtocol::onTimeout(Interest::Ptr &&interest) {
                             max_rtx)) {
     stats_->updateRetxCount(1);
 
-    callback = VOID_HANDLER;
-    socket_->getSocketOption(ConsumerCallbacksOptions::INTEREST_RETRANSMISSION,
-                             &callback);
-    if (*callback) {
-      (*callback)(*socket_->getInterface(), *interest);
+    if (*on_interest_retransmission_) {
+      (*on_interest_retransmission_)(*socket_->getInterface(), *interest);
     }
 
-    callback = VOID_HANDLER;
-    socket_->getSocketOption(ConsumerCallbacksOptions::INTEREST_OUTPUT,
-                             &callback);
-    if (*callback) {
-      (*callback)(*socket_->getInterface(), *interest);
+    if (*on_interest_output_) {
+      (*on_interest_output_)(*socket_->getInterface(), *interest);
     }
 
     if (!is_running_) {
@@ -463,7 +441,6 @@ void RaaqmTransportProtocol::onTimeout(Interest::Ptr &&interest) {
     }
 
     interest_retransmissions_[segment & mask]++;
-
     interest_to_retransmit_.push(std::move(interest));
 
     scheduleNextInterests();
@@ -507,7 +484,7 @@ void RaaqmTransportProtocol::scheduleNextInterests() {
   }
 }
 
-void RaaqmTransportProtocol::sendInterest(std::uint64_t next_suffix) {
+bool RaaqmTransportProtocol::sendInterest(std::uint64_t next_suffix) {
   auto interest = getPacket();
   core::Name *name;
   socket_->getSocketOption(GeneralTransportOptions::NETWORK_NAME, &name);
@@ -519,15 +496,12 @@ void RaaqmTransportProtocol::sendInterest(std::uint64_t next_suffix) {
                            interest_lifetime);
   interest->setLifetime(interest_lifetime);
 
-  ConsumerInterestCallback *callback = VOID_HANDLER;
-  socket_->getSocketOption(ConsumerCallbacksOptions::INTEREST_OUTPUT,
-                           &callback);
-  if (*callback) {
-    callback->operator()(*socket_->getInterface(), *interest);
+  if (*on_interest_output_) {
+    on_interest_output_->operator()(*socket_->getInterface(), *interest);
   }
 
   if (TRANSPORT_EXPECT_FALSE(!is_running_ && !is_first_)) {
-    return;
+    return false;
   }
 
   // This is set to ~0 so that the next interest_retransmissions_ + 1,
@@ -535,6 +509,8 @@ void RaaqmTransportProtocol::sendInterest(std::uint64_t next_suffix) {
   interest_retransmissions_[next_suffix & mask] = ~0;
   interest_timepoints_[next_suffix & mask] = utils::SteadyClock::now();
   sendInterest(std::move(interest));
+
+  return true;
 }
 
 void RaaqmTransportProtocol::sendInterest(Interest::Ptr &&interest) {
@@ -564,7 +540,7 @@ void RaaqmTransportProtocol::updateRtt(uint64_t segment) {
       rate_estimator_->onRttUpdate((double)rtt.count());
     }
 
-    cur_path_->insertNewRtt(rtt.count());
+    cur_path_->insertNewRtt(rtt.count(), now);
     cur_path_->smoothTimer();
 
     if (cur_path_->newPropagationDelayAvailable()) {
@@ -595,18 +571,15 @@ void RaaqmTransportProtocol::updateStats(uint32_t suffix, uint64_t rtt,
   stats_->updateAverageWindowSize(current_window_size_);
 
   // Call statistics callback
-  ConsumerTimerCallback *stats_callback = VOID_HANDLER;
-  socket_->getSocketOption(ConsumerCallbacksOptions::STATS_SUMMARY,
-                           &stats_callback);
-  if (*stats_callback) {
+  if (*stats_summary_) {
     auto dt = std::chrono::duration_cast<utils::Milliseconds>(now - t0_);
 
     uint32_t timer_interval_milliseconds = 0;
     socket_->getSocketOption(GeneralTransportOptions::STATS_INTERVAL,
                              timer_interval_milliseconds);
     if (dt.count() > timer_interval_milliseconds) {
-      (*stats_callback)(*socket_->getInterface(), *stats_);
-      t0_ = utils::SteadyClock::now();
+      (*stats_summary_)(*socket_->getInterface(), *stats_);
+      t0_ = now;
     }
   }
 }
diff --git a/libtransport/src/protocols/raaqm.h b/libtransport/src/protocols/raaqm.h
index 412967770..ecc466755 100644
--- a/libtransport/src/protocols/raaqm.h
+++ b/libtransport/src/protocols/raaqm.h
@@ -79,7 +79,7 @@ class RaaqmTransportProtocol : public TransportProtocol,
 
   virtual void scheduleNextInterests() override;
 
-  void sendInterest(std::uint64_t next_suffix);
+  bool sendInterest(std::uint64_t next_suffix);
 
   void sendInterest(Interest::Ptr &&interest);
 
diff --git a/libtransport/src/protocols/raaqm_data_path.cc b/libtransport/src/protocols/raaqm_data_path.cc
index 439549c85..8bbbadcf2 100644
--- a/libtransport/src/protocols/raaqm_data_path.cc
+++ b/libtransport/src/protocols/raaqm_data_path.cc
@@ -48,7 +48,8 @@ RaaqmDataPath::RaaqmDataPath(double drop_factor,
       average_rtt_(0),
       alpha_(ALPHA) {}
 
-RaaqmDataPath &RaaqmDataPath::insertNewRtt(uint64_t new_rtt) {
+RaaqmDataPath &RaaqmDataPath::insertNewRtt(uint64_t new_rtt,
+                                           const utils::TimePoint &now) {
   rtt_ = new_rtt;
   rtt_samples_.pushBack(new_rtt);
 
@@ -60,7 +61,7 @@ RaaqmDataPath &RaaqmDataPath::insertNewRtt(uint64_t new_rtt) {
     prop_delay_ = rtt_min_;
   }
 
-  last_received_pkt_ = utils::SteadyClock::now();
+  last_received_pkt_ = now;
 
   return *this;
 }
diff --git a/libtransport/src/protocols/raaqm_data_path.h b/libtransport/src/protocols/raaqm_data_path.h
index 6f2afde72..3f037bc76 100644
--- a/libtransport/src/protocols/raaqm_data_path.h
+++ b/libtransport/src/protocols/raaqm_data_path.h
@@ -45,7 +45,7 @@ class RaaqmDataPath {
    * max of RTT.
    * @param new_rtt is the value of the new RTT
    */
-  RaaqmDataPath &insertNewRtt(uint64_t new_rtt);
+  RaaqmDataPath &insertNewRtt(uint64_t new_rtt, const utils::TimePoint &now);
 
   /**
    * @brief Update the path statistics
diff --git a/libtransport/src/protocols/rtc.cc b/libtransport/src/protocols/rtc.cc
index 0ac3839dd..72abb599a 100644
--- a/libtransport/src/protocols/rtc.cc
+++ b/libtransport/src/protocols/rtc.cc
@@ -288,15 +288,12 @@ void RTCTransportProtocol::updateStats(uint32_t round_duration) {
   uint32_t BW = (uint32_t)ceil(estimatedBw_);
   computeMaxWindow(BW, BDP);
 
-  ConsumerTimerCallback *stats_callback = nullptr;
-  socket_->getSocketOption(ConsumerCallbacksOptions::STATS_SUMMARY,
-                           &stats_callback);
-  if (*stats_callback) {
+  if (*stats_summary_) {
     // Send the stats to the app
     stats_->updateQueuingDelay(queuingDelay_);
     stats_->updateLossRatio(lossRate_);
     stats_->updateAverageRtt(pathTable_[producerPathLabels_[1]]->getMinRtt());
-    (*stats_callback)(*socket_->getInterface(), *stats_);
+    (*stats_summary_)(*socket_->getInterface(), *stats_);
   }
   // bound also by interest lifitime* production rate
   if (!gotNack_) {
@@ -451,13 +448,8 @@ void RTCTransportProtocol::sendInterest(Name *interest_name, bool rtx) {
                            interestLifetime);
   interest->setLifetime(uint32_t(interestLifetime));
 
-  ConsumerInterestCallback *on_interest_output = nullptr;
-
-  socket_->getSocketOption(ConsumerCallbacksOptions::INTEREST_OUTPUT,
-                           &on_interest_output);
-
-  if (*on_interest_output) {
-    (*on_interest_output)(*socket_->getInterface(), *interest);
+  if (*on_interest_output_) {
+    (*on_interest_output_)(*socket_->getInterface(), *interest);
   }
 
   if (TRANSPORT_EXPECT_FALSE(!is_running_ && !is_first_)) {
@@ -890,11 +882,8 @@ void RTCTransportProtocol::onContentObject(
   uint32_t segmentNumber = content_object->getName().getSuffix();
   uint32_t pkt = segmentNumber & modMask_;
 
-  ConsumerContentObjectCallback *callback_content_object = nullptr;
-  socket_->getSocketOption(ConsumerCallbacksOptions::CONTENT_OBJECT_INPUT,
-                           &callback_content_object);
-  if (*callback_content_object) {
-    (*callback_content_object)(*socket_->getInterface(), *content_object);
+  if (*on_content_object_input_) {
+    (*on_content_object_input_)(*socket_->getInterface(), *content_object);
   }
 
   if (segmentNumber >= HICN_MIN_PROBE_SEQ) {
diff --git a/libtransport/src/utils/membuf.cc b/libtransport/src/utils/membuf.cc
index e75e85b35..94e5b13a1 100644
--- a/libtransport/src/utils/membuf.cc
+++ b/libtransport/src/utils/membuf.cc
@@ -102,8 +102,6 @@ struct MemBuf::HeapStorage {
 };
 
 struct MemBuf::HeapFullStorage {
-  // Make sure jemalloc allocates from the 64-byte class.  Putting this here
-  // because HeapStorage is private so it can't be at namespace level.
   static_assert(sizeof(HeapStorage) <= 64,
                 "MemBuf may not grow over 56 bytes!");