diff --git a/README.md b/README.md
index ab3564f..797294d 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,24 @@
 
 `c++11` `c++14` `c++17` focused libraries ("head-only" big law is good!) for personal use.
 
+
+|item| describe |
+|-|-|
+|cfg| a hash table|
+|channel | a Rust-like mpsc channel implementation based on lock-free mpsc  (multi-producer single-consumer)  queue|
+|clp | a very simple commandline parser for C++17's features test |
+| crypt | I don't know..|
+| fake_variant | a tuple-like class |
+|file_sort | sort numbers in a big file (bitset and divide-conquer) |
+|logging | a log library based on mpsc queue |
+|loop_per_thread | a test for loop per thread paradigm |
+|rbtree | a red-black implementation |
+|signal | a simple signal-slot implementation |
+|string_ext| an extended std::string |
+|threadpool | a simple thread pool implementation via std::thread and a lock-based task queue|
+|variant | a variant implementation for C++11 |
+| typelist.cpp | a loki-like typelist implemented by modern C++ |
+
 ### LICENSE
 [GPLv3](./LICENSE)([with exception](https://gcc.gnu.org/onlinedocs/libstdc++/manual/license.html))
 
diff --git a/channel/README.md b/channel/README.md
index e4e6a4f..c40344c 100644
--- a/channel/README.md
+++ b/channel/README.md
@@ -3,3 +3,41 @@
 A C++ implementation of **MPSC** (multi-producer single-consumer) [channel](./channel.h).
 
 see [mpsc.rs](./mpsc.rs).
+
+-----
+`rustc -C opt-level=3 mpsc.rs -o a.out
+` [rustc 1.20.0-nightly]
+```
+./a.out 10000000
+thread 0 done
+thread 2 done
+thread 1 done
+thread 0 => 10000000
+thread 1 => 10000000
+thread 2 => 10000000
+receiver done.
+3.118793157
+```
+`g++ -std=c++17 test.cpp -pthread -O3` [g++ (SUSE Linux) 7.1.1 20170629]
+```
+thread 0 done
+thread 2 done
+thread 1 done
+thread 0 => 10000000
+thread 1 => 10000000
+thread 2 => 10000000
+receiver done.
+3.111892014
+```
+`g++ -std=c++17 test.cpp -pthread -O3 -DJEMALLOC -ljemalloc` [g++ (SUSE Linux) 7.1.1 20170629]
+```
+./a.out 10000000
+thread 2 done
+thread 0 done
+thread 1 done
+thread 0 => 10000000
+thread 1 => 10000000
+thread 2 => 10000000
+receiver done.
+2.148938502
+```
diff --git a/channel/channel.h b/channel/channel.h
index d61b15d..3f4c87d 100644
--- a/channel/channel.h
+++ b/channel/channel.h
@@ -147,9 +147,8 @@ class Queue
 
   public:
     Queue()
-      : size_(0),
-      head_(alloc<Node>()),
-      tail_(head_.load())
+      : head_(alloc<Node>()),
+        tail_(head_.load())
     {
       auto tmp = head_.load();
       tmp->next.store(nullptr);
@@ -174,12 +173,7 @@ class Queue
 
     bool empty() const
     {
-      return size_ == 0;
-    }
-
-    size_t unsafe_size() const
-    {
-      return size_.load();
+      return tail_->next.load(std::memory_order_acquire) == nullptr;
     }
 
     void push(const T& data)
@@ -189,7 +183,6 @@ class Queue
       tmp->next.store(nullptr, std::memory_order_relaxed);
       auto old_head = head_.exchange(tmp, std::memory_order_acq_rel);
       old_head->next.store(tmp, std::memory_order_release);
-      size_ += 1;
     }
 
     void push(T&& data)
@@ -199,7 +192,6 @@ class Queue
       tmp->next.store(nullptr, std::memory_order_relaxed);
       auto old_head = head_.exchange(tmp, std::memory_order_acq_rel);
       old_head->next.store(tmp, std::memory_order_release);
-      size_ += 1;
     }
 
     bool try_pop(T& data)
@@ -210,12 +202,10 @@ class Queue
       data = std::move(next->data);
       dealloc(tail_);
       tail_ = next;
-      size_ -= 1;
       return true;
     }
 
   private:
-    std::atomic<size_t> size_;
     std::atomic<Node*> head_;
     Node* tail_;
 };
diff --git a/clp/clp.h b/clp/clp.h
index cdce8f2..f7f1c1a 100644
--- a/clp/clp.h
+++ b/clp/clp.h
@@ -201,7 +201,7 @@ namespace nm
             return;
           }
           // get key
-          if(iter->find_first_of(delim) != iter->npos && *iter != "--")
+          if(iter->find(delim) != iter->npos && *iter != "--")
           {
             tmp = iter->substr(delim.length());
             has_key = true;
@@ -236,7 +236,7 @@ namespace nm
             }
           }
           // no value
-          else if(iter->find_first_of(delim) < delim.size())
+          else if(iter->find(delim) < delim.size())
           {
             --iter;
             c_.emplace(tmp);
diff --git a/loop_per_thread/server.cpp b/loop_per_thread/server.cpp
index 4c8eb6e..5c94dab 100644
--- a/loop_per_thread/server.cpp
+++ b/loop_per_thread/server.cpp
@@ -174,14 +174,13 @@ class Session : public std::enable_shared_from_this<Session>
                            //std::cerr << ec.message() << std::endl;
                            return;
                          }
-                         buf_.consume(bytes);
                          processing();
                        });
     }
 
     void processing()
     {
-      async_write(socket_, boost::asio::buffer("pong\n"),
+      async_write(socket_, buf_,
                   [this, self = shared_from_this()](const error_code& ec, size_t)
                   {
                     if(ec)
diff --git a/typelist.cpp b/typelist.cpp
index 0a70ed4..f1e2d67 100644
--- a/typelist.cpp
+++ b/typelist.cpp
@@ -219,7 +219,6 @@ namespace nm
       template<typename F> constexpr static void call(F) {}
     };
 
-    // common idiom CRTP
     template<typename... Args> struct overloaded : Args...
     {
       using Args::operator()...;