diff --git a/contrib/csnippets/config.h.in b/contrib/csnippets/config.h.in
index 0690bb6..970d94a 100644
--- a/contrib/csnippets/config.h.in
+++ b/contrib/csnippets/config.h.in
@@ -4,7 +4,6 @@
 #ifndef CSNIPPETS_CONFIG_H
 #define CSNIPPETS_CONFIG_H
 
-#cmakedefine01 HAVE_CLOCK_GETTIME
 #cmakedefine01 HAVE_SYSLOG
 #cmakedefine01 HAVE_LOCALTIME_R
 
diff --git a/contrib/csnippets/utils/buffer.h b/contrib/csnippets/utils/buffer.h
index 94e1302..62ea3d8 100644
--- a/contrib/csnippets/utils/buffer.h
+++ b/contrib/csnippets/utils/buffer.h
@@ -267,18 +267,18 @@ static inline bool vbuf_boundcheck(struct vbuffer *vbuf)
 /**
  * @brief Adjust vbuffer allocation while preserving data.
  * @param vbuf If NULL, new buffer may be allocated.
- * @param want Expected vbuffer overall size in bytes.
+ * @param want Expected vbuffer overall capacity in bytes.
  * @return If failed, the allocation remains unchanged.
  * @details usage: `vbuf = VBUF_RESIZE(vbuf, 0); // shrink the buffer to fit`
  */
 #define VBUF_RESIZE(vbuf, want)                                                \
 	(VBUF_ASSERT_BOUND(vbuf),                                              \
-	 vbuf_alloc((vbuf), MAX(VBUF_LEN(vbuf), (want))))
+	 vbuf_alloc((vbuf), MAX((vbuf) != NULL ? (vbuf)->len : 0, (want))))
 
 /**
  * @brief Expand vbuffer allocation.
  * @param vbuf If NULL, new buffer may be allocated.
- * @param want Expected vbuffer overall size in bytes.
+ * @param want Expected minimum vbuffer overall capacity in bytes.
  * @return If failed, the allocation remains unchanged.
  * @details usage: `vbuf = VBUF_RESERVE(vbuf, 100);`
  */
@@ -301,7 +301,7 @@ static inline bool vbuf_boundcheck(struct vbuffer *vbuf)
 
 /**
  * @brief Append literal string to vbuffer.
- * @param vbuf If NULL, the minimum required size is allocated.
+ * @param vbuf If NULL, new buffer is allocated.
  * @return If the allocation fails, the data is truncated.
  * @see VBUF_APPEND
  * @details usage: `vbuf = VBUF_APPENDSTR(vbuf, "some string");`
@@ -312,7 +312,7 @@ static inline bool vbuf_boundcheck(struct vbuffer *vbuf)
 
 /**
  * @brief Append formatted string to vbuffer.
- * @param vbuf If NULL, the minimum required size is allocated.
+ * @param vbuf If NULL, new buffer is allocated.
  * @return If the allocation fails, the data is truncated.
  * @see VBUF_APPEND
  * @details usage: vbuf = VBUF_APPENDF(vbuf, "%s: %s\r\n", "Content-Type", "text/plain");
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 84c3199..21501a4 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -18,7 +18,6 @@ else()
 endif()
 
 include(CheckSymbolExists)
-check_symbol_exists(clock_gettime "time.h" HAVE_CLOCK_GETTIME)
 check_symbol_exists(sendmmsg "sys/socket.h" HAVE_API_SENDMMSG)
 check_symbol_exists(SYS_sendmmsg "sys/syscall.h" HAVE_SYS_SENDMMSG)
 check_symbol_exists(recvmmsg "sys/socket.h" HAVE_API_RECVMMSG)
diff --git a/src/server.c b/src/server.c
index 30c71a5..8649cad 100644
--- a/src/server.c
+++ b/src/server.c
@@ -398,7 +398,8 @@ server_new(struct ev_loop *loop, const struct config *restrict conf)
 			conf->keepalive * 3.0 + ping_timeout, 10.0, 1800.0),
 		.ping_timeout = ping_timeout,
 		.time_wait = conf->time_wait,
-		.last_clock = -1,
+		.last_cputime = TSTAMP_NIL,
+		.last_monotime = TSTAMP_NIL,
 	};
 
 	{
@@ -772,36 +773,31 @@ static struct vbuffer *append_traffic_stats(
 		/* total */ tcp_rx, tcp_tx, kcp_rx, kcp_tx, pkt_rx, pkt_tx);
 }
 
-static double clock_cputime(void)
-{
-#if HAVE_CLOCK_GETTIME
-	struct timespec t;
-	if (clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &t)) {
-		return NAN;
-	}
-	return t.tv_sec + t.tv_nsec * 1e-9;
-#else
-	const clock_t clk = clock();
-	if (clk == (clock_t)-1) {
-		return NAN;
-	}
-	return (double)clk / CLOCKS_PER_SEC;
-#endif
-}
-
-static bool update_load(
+static const char *format_load(
 	struct server *restrict s, char *buf, const size_t bufsize,
-	const double dt)
+	const char *fail)
 {
-	const double last = s->last_clock;
-	const double now = clock_cputime();
-	s->last_clock = now;
-	if (!isfinite(now) || !isfinite(last) || now < last) {
-		return false;
+	const char *load_str = fail;
+	double monotime, cputime;
+	struct timespec t;
+	if (clock_gettime(CLOCK_MONOTONIC, &t)) {
+		return load_str;
 	}
-	const double load = (now - last) / dt * 100.0;
-	(void)snprintf(buf, bufsize, "%.03f%%", load);
-	return true;
+	monotime = t.tv_sec + t.tv_nsec * 1e-9;
+	if (clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &t)) {
+		return load_str;
+	}
+	cputime = t.tv_sec + t.tv_nsec * 1e-9;
+	if (s->last_cputime != TSTAMP_NIL && s->last_monotime != TSTAMP_NIL) {
+		const double busy = cputime - s->last_cputime;
+		const double total = monotime - s->last_monotime;
+		const double load = busy / total * 100.0;
+		(void)snprintf(buf, bufsize, "%.03f%%", load);
+		load_str = buf;
+	}
+	s->last_cputime = cputime;
+	s->last_monotime = monotime;
+	return load_str;
 }
 
 struct vbuffer *
@@ -864,18 +860,13 @@ struct vbuffer *server_stats(
 
 	buf = append_traffic_stats(buf, &s->stats);
 
-	{
-		char load_buf[16];
-		const char *load_str = "(unknown)";
-		if (update_load(s, load_buf, sizeof(load_buf), dt)) {
-			load_str = load_buf;
-		}
-		FORMAT_BYTES(dpkt_rx, dstats.pkt_rx / dt);
-		FORMAT_BYTES(dpkt_tx, dstats.pkt_tx / dt);
-		buf = VBUF_APPENDF(
-			buf, "  = load: %s; pkt: %s/s, %s/s; uptime: %s\n",
-			load_str, dpkt_rx, dpkt_tx, uptime_str);
-	}
+	FORMAT_BYTES(dpkt_rx, dstats.pkt_rx / dt);
+	FORMAT_BYTES(dpkt_tx, dstats.pkt_tx / dt);
+	char load_buf[16];
+	buf = VBUF_APPENDF(
+		buf, "  = load: %s; pkt: %s/s, %s/s; uptime: %s\n",
+		format_load(s, load_buf, sizeof(load_buf), "(unknown)"),
+		dpkt_rx, dpkt_tx, uptime_str);
 #undef FORMAT_BYTES
 
 	/* rotate stats */
diff --git a/src/server.h b/src/server.h
index 423dc48..4be8215 100644
--- a/src/server.h
+++ b/src/server.h
@@ -85,7 +85,7 @@ struct server {
 		ev_tstamp started;
 		ev_tstamp last_stats_time;
 		ev_tstamp last_resolve_time;
-		double last_clock;
+		double last_cputime, last_monotime;
 	};
 };