Keep DATA pacing units consistent and test startup delay exit

src/transport_layer/etcp_loadbalancer.c

@@ -103,10 +103,6 @@ int etcp_loadbalancer_send(struct ETCP_DGRAM* dgram) {
     }
     
     struct ETCP_LINK* link = dgram->link;
-    size_t pkt_size = dgram->data_len + sizeof(uint16_t);  // Include timestamp
-    
-//    DEBUG_INFO(DEBUG_CATEGORY_ETCP, "[%s] sending dgram on link=%p, size=%zu", etcp->log_name, link, pkt_size);
-    
     // Encrypt and send (from etcp_connections.c)
     int send_result = etcp_encrypt_send(dgram);
     etcp_tx_complete(dgram, send_result >= 0);
@@ -130,7 +126,7 @@ int etcp_loadbalancer_send(struct ETCP_DGRAM* dgram) {
             link->shaper_load_time_tb = now_tb - SHAPER_BURST_DELAY_TB; link->shaper_sub_nanotime = 0;
         }
         // Ставка B/s; SUB_MODULO соответствует 0.1мс, один sub равен 0.1нс.
-        uint64_t tx_sub = ((uint64_t)pkt_size * 10000000000ULL + link->bbr_pacing_rate - 1) / link->bbr_pacing_rate;
+        uint64_t tx_sub = ((uint64_t)dgram->payload_len * 10000000000ULL + link->bbr_pacing_rate - 1) / link->bbr_pacing_rate;
         
         // Add to load
         link->shaper_sub_nanotime += tx_sub;

tests/test_etcp_bbr.c

@@ -380,6 +380,36 @@ static int test_initial_pacing(void) {
     PASS(); return 0;
 }
 
+/* Один всплеск очереди не завершает разгон; целый раунд выше бюджета завершает, не меняя BW искусственно. */
+static int test_startup_delay_exit(void) {
+    MSEG("STARTUP delay exit requires an entire elevated RTT round");
+    for (unsigned enabled = 0; enabled < 2; enabled++) {
+        struct bbr s = { .now_tb = 10000 }; bbr_init(&s);
+        s.queue_budget_us = enabled ? 20000 : 0;
+        s.min_rtt_us = s.probe_rtt_min_us = 200000; s.has_seen_rtt = 1;
+        uint32_t cwnd = 400000, pacing = 2000000;
+        struct bbr_rate_sample rs = { .acked_sacked = 1000, .delivered = 100000, .interval_us = 100000,
+            .rtt_us = 219000, .tx_in_flight = 400000 };
+        bbr_main(&s, &rs, &cwnd, &pacing, 1000, 399000, 1);
+        rs.rtt_us = 250000;
+        bbr_main(&s, &rs, &cwnd, &pacing, 1000, 399000, 1);
+        rs.prior_delivered = s.delivered;
+        bbr_main(&s, &rs, &cwnd, &pacing, 1000, 399000, 1);
+        if (s.mode != BBR_STARTUP) FAIL("one high RTT must not override a round minimum below the budget");
+        rs.rtt_us = 0;
+        bbr_main(&s, &rs, &cwnd, &pacing, 1000, 399000, 1);
+        if (s.mode != BBR_STARTUP) FAIL("incomplete RTT round must not terminate startup");
+        rs.prior_delivered = s.delivered;
+        bbr_main(&s, &rs, &cwnd, &pacing, 1000, 399000, 1);
+        DEBUG_INFO(DEBUG_CATEGORY_DEBUG, "BBR STARTUP delay: enabled=%u mode=%u full_bw=%u pace=%u",
+            enabled, s.mode, s.full_bw_reached, pacing);
+        if (enabled && (s.mode != BBR_DRAIN || !s.full_bw_reached || pacing >= 1000000))
+            FAIL("sustained queue must enter DRAIN using the measured bandwidth");
+        if (!enabled && s.mode != BBR_STARTUP) FAIL("disabled delay budget must preserve bandwidth-based startup");
+    }
+    PASS(); return 0;
+}
+
 int main(void)
 {
     debug_config_init(); debug_set_level(DEBUG_LEVEL_ERROR); debug_set_category_level(DEBUG_CATEGORY_DEBUG, DEBUG_LEVEL_INFO);
@@ -402,6 +432,7 @@ int main(void)
     test_queue_budget_floor_and_startup();
     test_queue_budget_fast_path();
     test_initial_pacing();
+    test_startup_delay_exit();
     printf("\n=== Results: %d/%d passed, %d failed ===\n", test_passed, test_total, test_failed);
     return test_failed ? 1 : 0;
 }