Client: improve operation with iovec

Allocate iovec simply on stack. Don't use NETWORK::readyToRecv anymore, use READAHEAD instead. Part of #28
tarantool · Aug 31, 2022 · 0bcd230 · 0bcd230
1 parent f65951d
commit 0bcd230
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Showing 3 changed files with 32 additions and 63 deletions.
diff --git a/src/Client/Connection.hpp b/src/Client/Connection.hpp
@@ -41,6 +41,9 @@
 /** rid == request id */
 typedef size_t rid_t;
 
+static constexpr size_t CONN_READAHEAD = 64 * 1024;
+static constexpr size_t IOVEC_MAX_SIZE = 32;
+
 struct ConnectionError {
 	std::string msg;
 	//Saved in case connection fails due to system error.
@@ -86,9 +89,6 @@ struct ConnectionImpl
 	Greeting greeting;
 	bool is_greeting_received;
 	std::unordered_map<rid_t, Response<BUFFER>> futures;
-
-	static constexpr size_t AVAILABLE_IOVEC_COUNT = 32;
-	struct iovec m_IOVecs[AVAILABLE_IOVEC_COUNT];
 };
 
 template<class BUFFER, class NetProvider>
@@ -172,15 +172,7 @@ class Connection
 	int getSocket() const;
 	void setSocket(int socket);
 	BUFFER& getInBuf();
-
-	template<class B, class N>
-	friend
-	struct iovec * outBufferToIOV(Connection<B, N> &conn, size_t *iov_len);
-
-	template<class B, class N>
-	friend
-	struct iovec * inBufferToIOV(Connection<B, N> &conn, size_t size,
-				     size_t *iov_len);
+	BUFFER& getOutBuf();
 
 	template<class B, class N>
 	friend
@@ -446,29 +438,10 @@ Connection<BUFFER, NetProvider>::getInBuf()
 }
 
 template<class BUFFER, class NetProvider>
-struct iovec *
-inBufferToIOV(Connection<BUFFER, NetProvider> &conn, size_t size, size_t *iov_len)
-{
-	assert(iov_len != NULL);
-	BUFFER &buf = conn.impl->inBuf;
-	struct iovec *vecs = conn.impl->m_IOVecs;
-	typename BUFFER::iterator itr = buf.end();
-	buf.write({size});
-	*iov_len = buf.getIOV(itr, vecs,
-			      ConnectionImpl<BUFFER, NetProvider>::AVAILABLE_IOVEC_COUNT);
-	return vecs;
-}
-
-template<class BUFFER, class NetProvider>
-struct iovec *
-outBufferToIOV(Connection<BUFFER, NetProvider> &conn, size_t *iov_len)
+BUFFER&
+Connection<BUFFER, NetProvider>::getOutBuf()
 {
-	assert(iov_len != NULL);
-	BUFFER &buf = conn.impl->outBuf;
-	struct iovec *vecs = conn.impl->m_IOVecs;
-	*iov_len = buf.getIOV(buf.begin(), buf.end(), vecs,
-			      ConnectionImpl<BUFFER, NetProvider>::AVAILABLE_IOVEC_COUNT);
-	return vecs;
+	return impl->outBuf;
 }
 
 template<class BUFFER, class NetProvider>

diff --git a/src/Client/EpollNetProvider.hpp b/src/Client/EpollNetProvider.hpp
@@ -189,21 +189,14 @@ template<class BUFFER, class NETWORK>
 int
 EpollNetProvider<BUFFER, NETWORK>::recv(Conn_t &conn)
 {
-	size_t total = NETWORK::readyToRecv(conn.getSocket());
-	if (total < 0) {
-		LOG_ERROR("Failed to check socket: ioctl returned errno ",
-			  strerror(errno));
-		return -1;
-	}
-	if (total == 0) {
-		LOG_DEBUG("Socket ", conn.getSocket(), " has no data to read");
-		return 0;
-	}
-	size_t iov_cnt = 0;
-	/* Get IO vectors array pointing to the input buffer. */
-	struct iovec *iov = inBufferToIOV(conn, total, &iov_cnt);
+	auto &buf = conn.getInBuf();
+	auto itr = buf.template end<true>();
+	buf.write({CONN_READAHEAD});
+	struct iovec iov[IOVEC_MAX_SIZE];
+	size_t iov_cnt = buf.getIOV(itr, iov, IOVEC_MAX_SIZE);
+
 	ssize_t rcvd = NETWORK::recvall(conn.getSocket(), iov, iov_cnt, true);
-	hasNotRecvBytes(conn, total - (rcvd < 0 ? 0 : rcvd));
+	hasNotRecvBytes(conn, CONN_READAHEAD - (rcvd < 0 ? 0 : rcvd));
 	if (rcvd < 0) {
 		//Don't consider EWOULDBLOCK to be an error.
 		if (netWouldBlock(errno))
@@ -235,10 +228,12 @@ EpollNetProvider<BUFFER, NETWORK>::send(Conn_t &conn)
 {
 	while (hasDataToSend(conn)) {
 		size_t sent_bytes = 0;
-		size_t iov_cnt = 0;
-		struct iovec *iov = outBufferToIOV(conn, &iov_cnt);
+		struct iovec iov[IOVEC_MAX_SIZE];
+		auto &buf = conn.getOutBuf();
+		size_t iov_cnt = buf.getIOV(buf.template begin<true>(),
+					    iov, IOVEC_MAX_SIZE);
 		int rc = NETWORK::sendall(conn.getSocket(), iov, iov_cnt,
-						 &sent_bytes);
+					  &sent_bytes);
 		hasSentBytes(conn, sent_bytes);
 		if (rc != 0) {
 			if (netWouldBlock(errno)) {

diff --git a/src/Client/LibevNetProvider.hpp b/src/Client/LibevNetProvider.hpp
@@ -120,17 +120,14 @@ template<class BUFFER, class NETWORK>
 static inline int
 connectionReceive(Connection<BUFFER,  LibevNetProvider<BUFFER, NETWORK>> &conn)
 {
-	size_t total = NETWORK::readyToRecv(conn.getSocket());
-	if (total < 0) {
-		LOG_ERROR("Failed to check socket: ioctl returned errno ",
-			  strerror(errno));
-		return -1;
-	}
-	size_t iov_cnt = 0;
-	struct iovec *iov =
-		inBufferToIOV(conn, total, &iov_cnt);
+	auto &buf = conn.getInBuf();
+	auto itr = buf.template end<true>();
+	buf.write({CONN_READAHEAD});
+	struct iovec iov[IOVEC_MAX_SIZE];
+	size_t iov_cnt = buf.getIOV(itr, iov, IOVEC_MAX_SIZE);
+
 	ssize_t rcvd = NETWORK::recvall(conn.getSocket(), iov, iov_cnt, true);
-	hasNotRecvBytes(conn, total - (rcvd < 0 ? 0 : rcvd));
+	hasNotRecvBytes(conn, CONN_READAHEAD - (rcvd < 0 ? 0 : rcvd));
 	if (rcvd < 0) {
 		if (netWouldBlock(errno)) {
 			return 0;
@@ -184,8 +181,12 @@ connectionSend(Connection<BUFFER,  LibevNetProvider<BUFFER, NETWORK>> &conn)
 {
 	while (hasDataToSend(conn)) {
 		size_t sent_bytes = 0;
-		size_t iov_cnt = 0;
-		struct iovec *iov = outBufferToIOV(conn, &iov_cnt);
+
+		struct iovec iov[IOVEC_MAX_SIZE];
+		auto &buf = conn.getOutBuf();
+		size_t iov_cnt = buf.getIOV(buf.template begin<true>(),
+					    iov, IOVEC_MAX_SIZE);
+
 		int rc = NETWORK::sendall(conn.getSocket(), iov, iov_cnt,
 					  &sent_bytes);
 		hasSentBytes(conn, sent_bytes);