diff --git a/CHANGELOG.md b/CHANGELOG.md
index fe5520f..74a7267 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,14 @@
 
 
 
+
+## Version 0.2.0 - 2025-12-15
+
+Optimizes performance through enhanced socket settings and caching, reducing latency in connections. Adds host header validation to client requests and improves DNS resolution error handling for more reliable network operations.
+
+**Changes:** 4 files, 79 lines
+**Languages:** C (79 lines)
+
 ## Version 0.1.0 - 2025-12-15
 
 Implements zero-copy data forwarding to enhance connection performance. Caches patch buffers in connection structures and optimizes buffer compaction during read handling to reduce memory allocations.
diff --git a/src/connection.c b/src/connection.c
index 60b6e65..8a920f6 100644
--- a/src/connection.c
+++ b/src/connection.c
@@ -33,6 +33,11 @@
 
 connection_t connections[MAX_FDS];
 int epoll_fd = -1;
+time_t cached_time = 0;
+
+void connection_update_cached_time(void) {
+    cached_time = time(NULL);
+}
 
 void connection_init_all(void) {
     for (int i = 0; i < MAX_FDS; i++) {
@@ -75,20 +80,57 @@ void connection_set_tcp_keepalive(int fd) {
     }
 }
 
+void connection_set_tcp_nodelay(int fd) {
+    int yes = 1;
+    if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &yes, sizeof(yes)) < 0) {
+        log_debug("setsockopt TCP_NODELAY failed for fd %d: %s", fd, strerror(errno));
+    }
+}
+
+#ifdef TCP_QUICKACK
+void connection_set_tcp_quickack(int fd) {
+    int yes = 1;
+    if (setsockopt(fd, IPPROTO_TCP, TCP_QUICKACK, &yes, sizeof(yes)) < 0) {
+        log_debug("setsockopt TCP_QUICKACK failed for fd %d: %s", fd, strerror(errno));
+    }
+}
+#endif
+
+void connection_optimize_socket(int fd, int is_upstream) {
+    connection_set_tcp_nodelay(fd);
+    connection_set_tcp_keepalive(fd);
+#ifdef TCP_QUICKACK
+    if (!is_upstream) {
+        connection_set_tcp_quickack(fd);
+    }
+#endif
+    int sndbuf = is_upstream ? 262144 : 131072;
+    int rcvbuf = is_upstream ? 524288 : 131072;
+    setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &sndbuf, sizeof(sndbuf));
+    setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &rcvbuf, sizeof(rcvbuf));
+}
+
 void connection_add_to_epoll(int fd, uint32_t events) {
     struct epoll_event event = { .data.fd = fd, .events = events };
     if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, fd, &event) == -1) {
         log_error("epoll_ctl_add failed");
         close(fd);
+    } else if (fd >= 0 && fd < MAX_FDS) {
+        connections[fd].epoll_events = events;
     }
 }
 
 void connection_modify_epoll(int fd, uint32_t events) {
+    if (fd >= 0 && fd < MAX_FDS && connections[fd].epoll_events == events) {
+        return;
+    }
     struct epoll_event event = { .data.fd = fd, .events = events };
     if (epoll_ctl(epoll_fd, EPOLL_CTL_MOD, fd, &event) == -1) {
         if(errno != EBADF && errno != ENOENT) {
             log_debug("epoll_ctl_mod failed for fd %d: %s", fd, strerror(errno));
         }
+    } else if (fd >= 0 && fd < MAX_FDS) {
+        connections[fd].epoll_events = events;
     }
 }
 
@@ -153,7 +195,7 @@ void connection_accept(int listener_fd) {
         }
 
         connection_set_non_blocking(client_fd);
-        connection_set_tcp_keepalive(client_fd);
+        connection_optimize_socket(client_fd, 0);
         connection_add_to_epoll(client_fd, EPOLLIN);
 
         connection_t *conn = &connections[client_fd];
@@ -161,7 +203,7 @@ void connection_accept(int listener_fd) {
         conn->type = CONN_TYPE_CLIENT;
         conn->state = CLIENT_STATE_READING_HEADERS;
         conn->fd = client_fd;
-        conn->last_activity = time(NULL);
+        conn->last_activity = cached_time;
 
         if (buffer_init(&conn->read_buf, CHUNK_SIZE) < 0 ||
             buffer_init(&conn->write_buf, CHUNK_SIZE) < 0) {
@@ -293,7 +335,7 @@ int connection_do_read(connection_t *conn) {
 
     if (bytes_read > 0) {
         buf->tail += bytes_read;
-        conn->last_activity = time(NULL);
+        conn->last_activity = cached_time;
         if (conn->vhost_stats) {
             monitor_record_bytes(conn->vhost_stats, 0, bytes_read);
         }
@@ -325,7 +367,7 @@ int connection_do_write(connection_t *conn) {
 
     if (written > 0) {
         buffer_consume(buf, written);
-        conn->last_activity = time(NULL);
+        conn->last_activity = cached_time;
         if (conn->vhost_stats) {
             monitor_record_bytes(conn->vhost_stats, written, 0);
         }
@@ -425,7 +467,7 @@ static int try_upstream_connect(struct sockaddr_in *addr, int *out_fd) {
     }
 
     connection_set_non_blocking(up_fd);
-    connection_set_tcp_keepalive(up_fd);
+    connection_optimize_socket(up_fd, 1);
 
     int connect_result = connect(up_fd, (struct sockaddr*)addr, sizeof(*addr));
     if (connect_result < 0 && errno != EINPROGRESS) {
@@ -478,8 +520,10 @@ void connection_connect_to_upstream(connection_t *client, const char *data, size
         hints.ai_socktype = SOCK_STREAM;
 
         int gai_err = getaddrinfo(route->upstream_host, NULL, &hints, &result);
-        if (gai_err != 0) {
-            log_debug("DNS resolution failed for %s: %s", route->upstream_host, gai_strerror(gai_err));
+        if (gai_err != 0 || !result || !result->ai_addr) {
+            if (gai_err == 0 && result) freeaddrinfo(result);
+            log_debug("DNS resolution failed for %s: %s", route->upstream_host,
+                      gai_err ? gai_strerror(gai_err) : "no address returned");
             connection_send_error_response(client, 502, "Bad Gateway", "Cannot resolve upstream hostname");
             return;
         }
@@ -518,7 +562,7 @@ void connection_connect_to_upstream(connection_t *client, const char *data, size
     memset(up, 0, sizeof(connection_t));
     up->type = CONN_TYPE_UPSTREAM;
     up->fd = up_fd;
-    up->last_activity = time(NULL);
+    up->last_activity = cached_time;
     up->splice_pipe[0] = -1;
     up->splice_pipe[1] = -1;
 
@@ -690,6 +734,11 @@ static void handle_client_read(connection_t *conn) {
             break;
         }
 
+        if (conn->request.host[0] == '\0') {
+            connection_send_error_response(conn, 400, "Bad Request", "Missing Host header.");
+            return;
+        }
+
         long long body_len = (conn->request.content_length > 0) ? conn->request.content_length : 0;
         size_t total_request_len = headers_len + body_len;
 
@@ -804,8 +853,8 @@ static ssize_t splice_forward(connection_t *conn, connection_t *pair) {
         return -2;
     }
 
-    conn->last_activity = time(NULL);
-    pair->last_activity = time(NULL);
+    conn->last_activity = cached_time;
+    pair->last_activity = cached_time;
 
     if (conn->vhost_stats) {
         monitor_record_bytes(conn->vhost_stats, bytes_from_pipe, bytes_to_pipe);
@@ -1096,7 +1145,7 @@ static void handle_ssl_handshake(connection_t *conn) {
 }
 
 static void handle_write_event(connection_t *conn) {
-    conn->last_activity = time(NULL);
+    conn->last_activity = cached_time;
 
     if (conn->type == CONN_TYPE_UPSTREAM && conn->ssl && !conn->ssl_handshake_done) {
         handle_ssl_handshake(conn);
diff --git a/src/connection.h b/src/connection.h
index 919976c..fbb0db7 100644
--- a/src/connection.h
+++ b/src/connection.h
@@ -6,7 +6,9 @@
 
 extern connection_t connections[MAX_FDS];
 extern int epoll_fd;
+extern time_t cached_time;
 
+void connection_update_cached_time(void);
 void connection_init_all(void);
 void connection_setup_listener(int port);
 void connection_accept(int listener_fd);
diff --git a/src/main.c b/src/main.c
index c15a179..5138bc5 100644
--- a/src/main.c
+++ b/src/main.c
@@ -196,11 +196,13 @@ int main(int argc, char *argv[]) {
             break;
         }
 
+        connection_update_cached_time();
+
         for (int i = 0; i < n; i++) {
             connection_handle_event(&events[i]);
         }
 
-        time_t current_time = time(NULL);
+        time_t current_time = cached_time;
 
         if (current_time > last_monitor_update) {
             monitor_update();
diff --git a/src/types.h b/src/types.h
index fe648d2..e74ed29 100644
--- a/src/types.h
+++ b/src/types.h
@@ -6,6 +6,7 @@
 #endif
 #include <stdbool.h>
 #include <stddef.h>
+#include <stdint.h>
 #include <time.h>
 #include <openssl/ssl.h>
 #include <sqlite3.h>
@@ -103,6 +104,7 @@ typedef struct connection_s {
     size_t patch_buf_capacity;
     int splice_pipe[2];
     int can_splice;
+    uint32_t epoll_events;
 } connection_t;
 
 typedef struct {