diff --git a/agent/resources/test/flow_generator/report.result b/agent/resources/test/flow_generator/report.result
index 59f424a79f5..8e5e0828b73 100644
--- a/agent/resources/test/flow_generator/report.result
+++ b/agent/resources/test/flow_generator/report.result
@@ -246,18 +246,18 @@ TcpPerfStats {
     rtt_server_max: 0,
     srt_max: 10040,
     art_max: 30358,
-    cit_max: 0,
+    cit_max: 15033,
     rtt: 0,
     rtt_client_sum: 0,
     rtt_server_sum: 0,
     srt_sum: 10040,
     art_sum: 30358,
-    cit_sum: 0,
+    cit_sum: 15033,
     rtt_client_count: 0,
     rtt_server_count: 0,
     srt_count: 1,
     art_count: 1,
-    cit_count: 0,
+    cit_count: 1,
     syn_count: 0,
     synack_count: 0,
     retrans_syn_count: 0,
@@ -380,19 +380,19 @@ TcpPerfStats {
 }
 report after last packet:
 TcpPerfStats {
-    rtt_client_max: 20322,
-    rtt_server_max: 10226,
+    rtt_client_max: 0,
+    rtt_server_max: 0,
     srt_max: 10040,
     art_max: 30358,
     cit_max: 15033,
     rtt: 0,
-    rtt_client_sum: 20322,
-    rtt_server_sum: 10226,
+    rtt_client_sum: 0,
+    rtt_server_sum: 0,
     srt_sum: 10040,
     art_sum: 30358,
     cit_sum: 15033,
-    rtt_client_count: 1,
-    rtt_server_count: 1,
+    rtt_client_count: 0,
+    rtt_server_count: 0,
     srt_count: 1,
     art_count: 1,
     cit_count: 1,
@@ -450,18 +450,18 @@ TcpPerfStats {
 report after last packet:
 TcpPerfStats {
     rtt_client_max: 0,
-    rtt_server_max: 10226,
+    rtt_server_max: 0,
     srt_max: 10040,
     art_max: 30358,
     cit_max: 35355,
     rtt: 0,
     rtt_client_sum: 0,
-    rtt_server_sum: 10226,
+    rtt_server_sum: 0,
     srt_sum: 10040,
     art_sum: 30358,
     cit_sum: 35355,
     rtt_client_count: 0,
-    rtt_server_count: 1,
+    rtt_server_count: 0,
     srt_count: 1,
     art_count: 1,
     cit_count: 1,
diff --git a/agent/resources/test/flow_generator/rtt-full.result b/agent/resources/test/flow_generator/rtt-full.result
index 18431f0b002..39aef72ec3c 100644
--- a/agent/resources/test/flow_generator/rtt-full.result
+++ b/agent/resources/test/flow_generator/rtt-full.result
@@ -181,9 +181,9 @@ PerfData {
 3th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 318.2ms,
+        max: 309.1ms,
         updated: true,
     },
     rtt_1: TimeStats {
@@ -223,7 +223,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 0,
-    rtt_full: 225.4ms,
+    rtt_full: 525.4ms,
     retrans_0: 0,
     retrans_1: 0,
     retrans_syn_0: 0,
@@ -241,9 +241,9 @@ PerfData {
 4th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 318.2ms,
+        max: 309.1ms,
         updated: true,
     },
     rtt_1: TimeStats {
@@ -283,7 +283,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 0,
-    rtt_full: 225.4ms,
+    rtt_full: 525.4ms,
     retrans_0: 0,
     retrans_1: 0,
     retrans_syn_0: 0,
@@ -301,9 +301,9 @@ PerfData {
 5th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 318.2ms,
+        max: 309.1ms,
         updated: true,
     },
     rtt_1: TimeStats {
@@ -343,7 +343,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 0,
-    rtt_full: 225.4ms,
+    rtt_full: 525.4ms,
     retrans_0: 0,
     retrans_1: 0,
     retrans_syn_0: 0,
@@ -361,9 +361,9 @@ PerfData {
 6th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 318.2ms,
+        max: 309.1ms,
         updated: true,
     },
     rtt_1: TimeStats {
@@ -403,7 +403,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 0,
-    rtt_full: 225.4ms,
+    rtt_full: 525.4ms,
     retrans_0: 0,
     retrans_1: 0,
     retrans_syn_0: 0,
@@ -601,9 +601,9 @@ PerfData {
 3th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 74µs,
-        max: 74µs,
+        count: 2,
+        sum: 454.813ms,
+        max: 454.739ms,
         updated: true,
     },
     rtt_1: TimeStats {
@@ -643,7 +643,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 0,
-    rtt_full: 825µs,
+    rtt_full: 455.49ms,
     retrans_0: 0,
     retrans_1: 0,
     retrans_syn_0: 0,
@@ -661,9 +661,9 @@ PerfData {
 4th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 74µs,
-        max: 74µs,
+        count: 2,
+        sum: 454.813ms,
+        max: 454.739ms,
         updated: true,
     },
     rtt_1: TimeStats {
@@ -703,7 +703,7 @@ PerfData {
         updated: true,
     },
     retrans_sum: 0,
-    rtt_full: 825µs,
+    rtt_full: 455.49ms,
     retrans_0: 0,
     retrans_1: 0,
     retrans_syn_0: 0,
@@ -721,9 +721,9 @@ PerfData {
 5th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 74µs,
-        max: 74µs,
+        count: 2,
+        sum: 454.813ms,
+        max: 454.739ms,
         updated: true,
     },
     rtt_1: TimeStats {
@@ -763,7 +763,7 @@ PerfData {
         updated: true,
     },
     retrans_sum: 0,
-    rtt_full: 825µs,
+    rtt_full: 455.49ms,
     retrans_0: 0,
     retrans_1: 0,
     retrans_syn_0: 0,
@@ -781,9 +781,9 @@ PerfData {
 6th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 74µs,
-        max: 74µs,
+        count: 2,
+        sum: 454.813ms,
+        max: 454.739ms,
         updated: true,
     },
     rtt_1: TimeStats {
@@ -823,7 +823,7 @@ PerfData {
         updated: true,
     },
     retrans_sum: 0,
-    rtt_full: 825µs,
+    rtt_full: 455.49ms,
     retrans_0: 0,
     retrans_1: 0,
     retrans_syn_0: 0,
@@ -841,9 +841,9 @@ PerfData {
 7th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 74µs,
-        max: 74µs,
+        count: 2,
+        sum: 454.813ms,
+        max: 454.739ms,
         updated: true,
     },
     rtt_1: TimeStats {
@@ -883,7 +883,7 @@ PerfData {
         updated: true,
     },
     retrans_sum: 0,
-    rtt_full: 825µs,
+    rtt_full: 455.49ms,
     retrans_0: 0,
     retrans_1: 0,
     retrans_syn_0: 0,
@@ -901,9 +901,9 @@ PerfData {
 8th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 74µs,
-        max: 74µs,
+        count: 2,
+        sum: 454.813ms,
+        max: 454.739ms,
         updated: true,
     },
     rtt_1: TimeStats {
@@ -943,7 +943,7 @@ PerfData {
         updated: true,
     },
     retrans_sum: 0,
-    rtt_full: 825µs,
+    rtt_full: 455.49ms,
     retrans_0: 0,
     retrans_1: 0,
     retrans_syn_0: 0,
@@ -961,9 +961,9 @@ PerfData {
 9th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 74µs,
-        max: 74µs,
+        count: 2,
+        sum: 454.813ms,
+        max: 454.739ms,
         updated: true,
     },
     rtt_1: TimeStats {
@@ -1003,7 +1003,7 @@ PerfData {
         updated: true,
     },
     retrans_sum: 0,
-    rtt_full: 825µs,
+    rtt_full: 455.49ms,
     retrans_0: 0,
     retrans_1: 0,
     retrans_syn_0: 0,
@@ -1148,8 +1148,8 @@ PerfData {
     },
     rtt_1: TimeStats {
         count: 1,
-        sum: 216.3ms,
-        max: 216.3ms,
+        sum: 316.3ms,
+        max: 316.3ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -1208,8 +1208,8 @@ PerfData {
     },
     rtt_1: TimeStats {
         count: 1,
-        sum: 216.3ms,
-        max: 216.3ms,
+        sum: 316.3ms,
+        max: 316.3ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -1261,15 +1261,15 @@ PerfData {
 4th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 318.2ms,
+        max: 309.1ms,
         updated: true,
     },
     rtt_1: TimeStats {
         count: 1,
-        sum: 216.3ms,
-        max: 216.3ms,
+        sum: 316.3ms,
+        max: 316.3ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -1303,7 +1303,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 1,
-    rtt_full: 325.4ms,
+    rtt_full: 625.4ms,
     retrans_0: 1,
     retrans_1: 0,
     retrans_syn_0: 1,
@@ -1321,15 +1321,15 @@ PerfData {
 5th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 318.2ms,
+        max: 309.1ms,
         updated: true,
     },
     rtt_1: TimeStats {
         count: 1,
-        sum: 216.3ms,
-        max: 216.3ms,
+        sum: 316.3ms,
+        max: 316.3ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -1363,7 +1363,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 1,
-    rtt_full: 325.4ms,
+    rtt_full: 625.4ms,
     retrans_0: 1,
     retrans_1: 0,
     retrans_syn_0: 1,
@@ -1381,15 +1381,15 @@ PerfData {
 6th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 318.2ms,
+        max: 309.1ms,
         updated: true,
     },
     rtt_1: TimeStats {
         count: 1,
-        sum: 216.3ms,
-        max: 216.3ms,
+        sum: 316.3ms,
+        max: 316.3ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -1423,7 +1423,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 1,
-    rtt_full: 325.4ms,
+    rtt_full: 625.4ms,
     retrans_0: 1,
     retrans_1: 0,
     retrans_syn_0: 1,
@@ -1441,15 +1441,15 @@ PerfData {
 7th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 318.2ms,
+        max: 309.1ms,
         updated: true,
     },
     rtt_1: TimeStats {
         count: 1,
-        sum: 216.3ms,
-        max: 216.3ms,
+        sum: 316.3ms,
+        max: 316.3ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -1483,7 +1483,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 1,
-    rtt_full: 325.4ms,
+    rtt_full: 625.4ms,
     retrans_0: 1,
     retrans_1: 0,
     retrans_syn_0: 1,
@@ -1628,8 +1628,8 @@ PerfData {
     },
     rtt_1: TimeStats {
         count: 1,
-        sum: 216.3ms,
-        max: 216.3ms,
+        sum: 316.3ms,
+        max: 316.3ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -1687,9 +1687,9 @@ PerfData {
         updated: false,
     },
     rtt_1: TimeStats {
-        count: 1,
-        sum: 216.3ms,
-        max: 216.3ms,
+        count: 2,
+        sum: 848.9ms,
+        max: 532.6ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -1742,14 +1742,14 @@ PerfData {
 PerfData {
     rtt_0: TimeStats {
         count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        sum: 225.4ms,
+        max: 225.4ms,
         updated: true,
     },
     rtt_1: TimeStats {
-        count: 1,
-        sum: 216.3ms,
-        max: 216.3ms,
+        count: 2,
+        sum: 848.9ms,
+        max: 532.6ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -1801,15 +1801,15 @@ PerfData {
 5th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 750.8ms,
+        max: 525.4ms,
         updated: true,
     },
     rtt_1: TimeStats {
-        count: 1,
-        sum: 216.3ms,
-        max: 216.3ms,
+        count: 2,
+        sum: 848.9ms,
+        max: 532.6ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -1843,7 +1843,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 2,
-    rtt_full: 541.7ms,
+    rtt_full: 841.7ms,
     retrans_0: 1,
     retrans_1: 1,
     retrans_syn_0: 1,
@@ -1861,15 +1861,15 @@ PerfData {
 6th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 750.8ms,
+        max: 525.4ms,
         updated: true,
     },
     rtt_1: TimeStats {
-        count: 1,
-        sum: 216.3ms,
-        max: 216.3ms,
+        count: 2,
+        sum: 848.9ms,
+        max: 532.6ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -1903,7 +1903,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 2,
-    rtt_full: 541.7ms,
+    rtt_full: 841.7ms,
     retrans_0: 1,
     retrans_1: 1,
     retrans_syn_0: 1,
@@ -1921,15 +1921,15 @@ PerfData {
 7th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 750.8ms,
+        max: 525.4ms,
         updated: true,
     },
     rtt_1: TimeStats {
-        count: 1,
-        sum: 216.3ms,
-        max: 216.3ms,
+        count: 2,
+        sum: 848.9ms,
+        max: 532.6ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -1963,7 +1963,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 2,
-    rtt_full: 541.7ms,
+    rtt_full: 841.7ms,
     retrans_0: 1,
     retrans_1: 1,
     retrans_syn_0: 1,
@@ -1981,15 +1981,15 @@ PerfData {
 8th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 750.8ms,
+        max: 525.4ms,
         updated: true,
     },
     rtt_1: TimeStats {
-        count: 1,
-        sum: 216.3ms,
-        max: 216.3ms,
+        count: 2,
+        sum: 848.9ms,
+        max: 532.6ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -2023,7 +2023,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 2,
-    rtt_full: 541.7ms,
+    rtt_full: 841.7ms,
     retrans_0: 1,
     retrans_1: 1,
     retrans_syn_0: 1,
@@ -2228,8 +2228,8 @@ PerfData {
     },
     rtt_1: TimeStats {
         count: 2,
-        sum: 432.6ms,
-        max: 216.3ms,
+        sum: 748.9ms,
+        max: 532.6ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -2282,14 +2282,14 @@ PerfData {
 PerfData {
     rtt_0: TimeStats {
         count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        sum: 325.4ms,
+        max: 325.4ms,
         updated: true,
     },
     rtt_1: TimeStats {
         count: 2,
-        sum: 432.6ms,
-        max: 216.3ms,
+        sum: 748.9ms,
+        max: 532.6ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -2341,15 +2341,15 @@ PerfData {
 5th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 950.8ms,
+        max: 625.4ms,
         updated: true,
     },
     rtt_1: TimeStats {
         count: 2,
-        sum: 432.6ms,
-        max: 216.3ms,
+        sum: 748.9ms,
+        max: 532.6ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -2383,7 +2383,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 2,
-    rtt_full: 541.7ms,
+    rtt_full: 841.7ms,
     retrans_0: 1,
     retrans_1: 1,
     retrans_syn_0: 1,
@@ -2401,15 +2401,15 @@ PerfData {
 6th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 950.8ms,
+        max: 625.4ms,
         updated: true,
     },
     rtt_1: TimeStats {
         count: 2,
-        sum: 432.6ms,
-        max: 216.3ms,
+        sum: 748.9ms,
+        max: 532.6ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -2443,7 +2443,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 2,
-    rtt_full: 541.7ms,
+    rtt_full: 841.7ms,
     retrans_0: 1,
     retrans_1: 1,
     retrans_syn_0: 1,
@@ -2461,15 +2461,15 @@ PerfData {
 7th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 950.8ms,
+        max: 625.4ms,
         updated: true,
     },
     rtt_1: TimeStats {
         count: 2,
-        sum: 432.6ms,
-        max: 216.3ms,
+        sum: 748.9ms,
+        max: 532.6ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -2503,7 +2503,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 2,
-    rtt_full: 541.7ms,
+    rtt_full: 841.7ms,
     retrans_0: 1,
     retrans_1: 1,
     retrans_syn_0: 1,
@@ -2521,15 +2521,15 @@ PerfData {
 8th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 950.8ms,
+        max: 625.4ms,
         updated: true,
     },
     rtt_1: TimeStats {
         count: 2,
-        sum: 432.6ms,
-        max: 216.3ms,
+        sum: 748.9ms,
+        max: 532.6ms,
         updated: true,
     },
     art_0: TimeStats {
@@ -2563,7 +2563,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 2,
-    rtt_full: 541.7ms,
+    rtt_full: 841.7ms,
     retrans_0: 1,
     retrans_1: 1,
     retrans_syn_0: 1,
@@ -3259,10 +3259,10 @@ PerfData {
         updated: false,
     },
     art_1: TimeStats {
-        count: 0,
-        sum: 0ns,
-        max: 0ns,
-        updated: false,
+        count: 1,
+        sum: 990µs,
+        max: 990µs,
+        updated: true,
     },
     srt_0: TimeStats {
         count: 0,
@@ -3319,17 +3319,17 @@ PerfData {
         updated: false,
     },
     art_1: TimeStats {
+        count: 1,
+        sum: 990µs,
+        max: 990µs,
+        updated: true,
+    },
+    srt_0: TimeStats {
         count: 0,
         sum: 0ns,
         max: 0ns,
         updated: false,
     },
-    srt_0: TimeStats {
-        count: 1,
-        sum: 9µs,
-        max: 9µs,
-        updated: true,
-    },
     srt_1: TimeStats {
         count: 0,
         sum: 0ns,
@@ -3379,17 +3379,17 @@ PerfData {
         updated: false,
     },
     art_1: TimeStats {
+        count: 1,
+        sum: 990µs,
+        max: 990µs,
+        updated: true,
+    },
+    srt_0: TimeStats {
         count: 0,
         sum: 0ns,
         max: 0ns,
         updated: false,
     },
-    srt_0: TimeStats {
-        count: 1,
-        sum: 9µs,
-        max: 9µs,
-        updated: true,
-    },
     srt_1: TimeStats {
         count: 0,
         sum: 0ns,
@@ -3439,17 +3439,17 @@ PerfData {
         updated: false,
     },
     art_1: TimeStats {
+        count: 1,
+        sum: 990µs,
+        max: 990µs,
+        updated: true,
+    },
+    srt_0: TimeStats {
         count: 0,
         sum: 0ns,
         max: 0ns,
         updated: false,
     },
-    srt_0: TimeStats {
-        count: 1,
-        sum: 9µs,
-        max: 9µs,
-        updated: true,
-    },
     srt_1: TimeStats {
         count: 0,
         sum: 0ns,
@@ -3499,17 +3499,17 @@ PerfData {
         updated: false,
     },
     art_1: TimeStats {
+        count: 1,
+        sum: 990µs,
+        max: 990µs,
+        updated: true,
+    },
+    srt_0: TimeStats {
         count: 0,
         sum: 0ns,
         max: 0ns,
         updated: false,
     },
-    srt_0: TimeStats {
-        count: 1,
-        sum: 9µs,
-        max: 9µs,
-        updated: true,
-    },
     srt_1: TimeStats {
         count: 0,
         sum: 0ns,
@@ -3559,17 +3559,17 @@ PerfData {
         updated: false,
     },
     art_1: TimeStats {
+        count: 1,
+        sum: 990µs,
+        max: 990µs,
+        updated: true,
+    },
+    srt_0: TimeStats {
         count: 0,
         sum: 0ns,
         max: 0ns,
         updated: false,
     },
-    srt_0: TimeStats {
-        count: 1,
-        sum: 9µs,
-        max: 9µs,
-        updated: true,
-    },
     srt_1: TimeStats {
         count: 0,
         sum: 0ns,
diff --git a/agent/resources/test/flow_generator/rtt-syn.result b/agent/resources/test/flow_generator/rtt-syn.result
index a8759b46bd4..fa030f3ff73 100644
--- a/agent/resources/test/flow_generator/rtt-syn.result
+++ b/agent/resources/test/flow_generator/rtt-syn.result
@@ -181,9 +181,9 @@ PerfData {
 3th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 318.2ms,
+        max: 309.1ms,
         updated: true,
     },
     rtt_1: TimeStats {
@@ -223,7 +223,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 0,
-    rtt_full: 225.4ms,
+    rtt_full: 525.4ms,
     retrans_0: 0,
     retrans_1: 0,
     retrans_syn_0: 0,
@@ -241,9 +241,9 @@ PerfData {
 4th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 318.2ms,
+        max: 309.1ms,
         updated: true,
     },
     rtt_1: TimeStats {
@@ -283,7 +283,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 0,
-    rtt_full: 225.4ms,
+    rtt_full: 525.4ms,
     retrans_0: 0,
     retrans_1: 0,
     retrans_syn_0: 0,
@@ -301,9 +301,9 @@ PerfData {
 5th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 318.2ms,
+        max: 309.1ms,
         updated: true,
     },
     rtt_1: TimeStats {
@@ -343,7 +343,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 0,
-    rtt_full: 225.4ms,
+    rtt_full: 525.4ms,
     retrans_0: 0,
     retrans_1: 0,
     retrans_syn_0: 0,
@@ -361,9 +361,9 @@ PerfData {
 6th perf data:
 PerfData {
     rtt_0: TimeStats {
-        count: 1,
-        sum: 9.1ms,
-        max: 9.1ms,
+        count: 2,
+        sum: 318.2ms,
+        max: 309.1ms,
         updated: true,
     },
     rtt_1: TimeStats {
@@ -403,7 +403,7 @@ PerfData {
         updated: false,
     },
     retrans_sum: 0,
-    rtt_full: 225.4ms,
+    rtt_full: 525.4ms,
     retrans_0: 0,
     retrans_1: 0,
     retrans_syn_0: 0,
@@ -1057,8 +1057,8 @@ PerfData {
         updated: false,
     },
     cit: TimeStats {
-        count: 1,
-        sum: 10.141ms,
+        count: 2,
+        sum: 20.282ms,
         max: 10.141ms,
         updated: true,
     },
@@ -1117,8 +1117,8 @@ PerfData {
         updated: false,
     },
     cit: TimeStats {
-        count: 1,
-        sum: 10.141ms,
+        count: 2,
+        sum: 20.282ms,
         max: 10.141ms,
         updated: true,
     },
@@ -1165,10 +1165,10 @@ PerfData {
         updated: true,
     },
     srt_0: TimeStats {
-        count: 1,
-        sum: 182µs,
-        max: 182µs,
-        updated: true,
+        count: 0,
+        sum: 0ns,
+        max: 0ns,
+        updated: false,
     },
     srt_1: TimeStats {
         count: 0,
@@ -1177,8 +1177,8 @@ PerfData {
         updated: false,
     },
     cit: TimeStats {
-        count: 1,
-        sum: 10.141ms,
+        count: 2,
+        sum: 20.282ms,
         max: 10.141ms,
         updated: true,
     },
@@ -1225,10 +1225,10 @@ PerfData {
         updated: true,
     },
     srt_0: TimeStats {
-        count: 1,
-        sum: 182µs,
-        max: 182µs,
-        updated: true,
+        count: 0,
+        sum: 0ns,
+        max: 0ns,
+        updated: false,
     },
     srt_1: TimeStats {
         count: 0,
@@ -1237,8 +1237,8 @@ PerfData {
         updated: false,
     },
     cit: TimeStats {
-        count: 1,
-        sum: 10.141ms,
+        count: 2,
+        sum: 20.282ms,
         max: 10.141ms,
         updated: true,
     },
@@ -1285,10 +1285,10 @@ PerfData {
         updated: true,
     },
     srt_0: TimeStats {
-        count: 1,
-        sum: 182µs,
-        max: 182µs,
-        updated: true,
+        count: 0,
+        sum: 0ns,
+        max: 0ns,
+        updated: false,
     },
     srt_1: TimeStats {
         count: 0,
@@ -1297,8 +1297,8 @@ PerfData {
         updated: false,
     },
     cit: TimeStats {
-        count: 1,
-        sum: 10.141ms,
+        count: 2,
+        sum: 20.282ms,
         max: 10.141ms,
         updated: true,
     },
@@ -1345,10 +1345,10 @@ PerfData {
         updated: true,
     },
     srt_0: TimeStats {
-        count: 1,
-        sum: 182µs,
-        max: 182µs,
-        updated: true,
+        count: 0,
+        sum: 0ns,
+        max: 0ns,
+        updated: false,
     },
     srt_1: TimeStats {
         count: 0,
@@ -1357,8 +1357,8 @@ PerfData {
         updated: false,
     },
     cit: TimeStats {
-        count: 1,
-        sum: 10.141ms,
+        count: 2,
+        sum: 20.282ms,
         max: 10.141ms,
         updated: true,
     },
@@ -1405,10 +1405,10 @@ PerfData {
         updated: true,
     },
     srt_0: TimeStats {
-        count: 1,
-        sum: 182µs,
-        max: 182µs,
-        updated: true,
+        count: 0,
+        sum: 0ns,
+        max: 0ns,
+        updated: false,
     },
     srt_1: TimeStats {
         count: 0,
@@ -1417,8 +1417,8 @@ PerfData {
         updated: false,
     },
     cit: TimeStats {
-        count: 1,
-        sum: 10.141ms,
+        count: 2,
+        sum: 20.282ms,
         max: 10.141ms,
         updated: true,
     },
diff --git a/agent/src/flow_generator/perf/tcp.rs b/agent/src/flow_generator/perf/tcp.rs
index b5f99a9e8a2..96586668e24 100644
--- a/agent/src/flow_generator/perf/tcp.rs
+++ b/agent/src/flow_generator/perf/tcp.rs
@@ -665,6 +665,9 @@ impl TcpPerf {
         }
 
         if p.is_ack() {
+            // The first ACK packet sent by the server after handshake does not calculate rtt.
+            self.handshaking = fpd;
+
             // It is impossible to distinguish retransmission between ACK and ACK
             // keepalive. To avoid misunderstanding, retransmission of pure ACK
             // ==================================================================
@@ -761,6 +764,7 @@ impl TcpPerf {
                         (p.lookup_key.timestamp - oppo_dir.first_handshake_timestamp).into(),
                         RTT_MAX,
                     );
+
                     if !rtt.is_zero() {
                         self.perf_data.calc_rtt(rtt, fpd);
                     }
@@ -1189,6 +1193,7 @@ pub fn _meta_flow_perf_update(perf: &mut TcpPerf) {
      */
     // 1SYN
     let packet = MiniMetaPacket {
+        data_offset: 20,
         flags: TcpFlags::SYN,
         seq: 111,
         ack: 0,
@@ -1196,10 +1201,11 @@ pub fn _meta_flow_perf_update(perf: &mut TcpPerf) {
         ..Default::default()
     }
     .into();
-    perf.parse(&packet, false).unwrap();
+    perf.parse(&packet, true).unwrap();
 
     // 2SYN/ACK rttSum1=1
     let packet = MiniMetaPacket {
+        data_offset: 20,
         flags: TcpFlags::SYN_ACK,
         seq: 1111,
         ack: 112,
@@ -1207,10 +1213,11 @@ pub fn _meta_flow_perf_update(perf: &mut TcpPerf) {
         ..Default::default()
     }
     .into();
-    perf.parse(&packet, true).unwrap();
+    perf.parse(&packet, false).unwrap();
 
     // 1ACK rttSum0=10
     let packet = MiniMetaPacket {
+        data_offset: 20,
         flags: TcpFlags::ACK,
         seq: 112,
         ack: 1112,
@@ -1218,10 +1225,11 @@ pub fn _meta_flow_perf_update(perf: &mut TcpPerf) {
         ..Default::default()
     }
     .into();
-    perf.parse(&packet, false).unwrap();
+    perf.parse(&packet, true).unwrap();
 
     // 1ACK/LEN>0 len=100
     let packet = MiniMetaPacket {
+        data_offset: 20,
         flags: TcpFlags::ACK,
         seq: 112,
         ack: 1112,
@@ -1230,10 +1238,11 @@ pub fn _meta_flow_perf_update(perf: &mut TcpPerf) {
         ..Default::default()
     }
     .into();
-    perf.parse(&packet, false).unwrap();
+    perf.parse(&packet, true).unwrap();
 
     // 2ACK/LEN>0包，len=100 *art1=4
     let packet = MiniMetaPacket {
+        data_offset: 20,
         flags: TcpFlags::ACK,
         seq: 1112,
         ack: 212,
@@ -1242,10 +1251,11 @@ pub fn _meta_flow_perf_update(perf: &mut TcpPerf) {
         ..Default::default()
     }
     .into();
-    perf.parse(&packet, true).unwrap();
+    perf.parse(&packet, false).unwrap();
 
     // 2ACK 测试连续ACK包, 对RTT计算的影响
     let packet = MiniMetaPacket {
+        data_offset: 20,
         flags: TcpFlags::ACK,
         seq: 1112,
         ack: 212,
@@ -1253,10 +1263,11 @@ pub fn _meta_flow_perf_update(perf: &mut TcpPerf) {
         ..Default::default()
     }
     .into();
-    perf.parse(&packet, true).unwrap();
+    perf.parse(&packet, false).unwrap();
 
     // 2ACK/LEN>0 len=500
     let packet = MiniMetaPacket {
+        data_offset: 20,
         flags: TcpFlags::PSH_ACK,
         seq: 1212,
         ack: 212,
@@ -1265,10 +1276,11 @@ pub fn _meta_flow_perf_update(perf: &mut TcpPerf) {
         ..Default::default()
     }
     .into();
-    perf.parse(&packet, true).unwrap();
+    perf.parse(&packet, false).unwrap();
 
     // 1ACK srt0=16
     let packet = MiniMetaPacket {
+        data_offset: 20,
         flags: TcpFlags::ACK,
         seq: 212,
         ack: 1712,
@@ -1276,10 +1288,11 @@ pub fn _meta_flow_perf_update(perf: &mut TcpPerf) {
         ..Default::default()
     }
     .into();
-    perf.parse(&packet, false).unwrap();
+    perf.parse(&packet, true).unwrap();
 
     // 1ACK/LEN>0 len=200 art0=70
     let packet = MiniMetaPacket {
+        data_offset: 20,
         flags: TcpFlags::ACK,
         seq: 212,
         ack: 1712,
@@ -1288,10 +1301,11 @@ pub fn _meta_flow_perf_update(perf: &mut TcpPerf) {
         ..Default::default()
     }
     .into();
-    perf.parse(&packet, false).unwrap();
+    perf.parse(&packet, true).unwrap();
 
     // 2ACK *srt1=100
     let packet = MiniMetaPacket {
+        data_offset: 20,
         flags: TcpFlags::ACK,
         seq: 1712,
         ack: 412,
@@ -1299,10 +1313,11 @@ pub fn _meta_flow_perf_update(perf: &mut TcpPerf) {
         ..Default::default()
     }
     .into();
-    perf.parse(&packet, true).unwrap();
+    perf.parse(&packet, false).unwrap();
 
     // 2ACK/LEN>0 len=300 *art1=106
     let packet = MiniMetaPacket {
+        data_offset: 20,
         flags: TcpFlags::ACK,
         seq: 1712,
         ack: 412,
@@ -1311,7 +1326,7 @@ pub fn _meta_flow_perf_update(perf: &mut TcpPerf) {
         ..Default::default()
     }
     .into();
-    perf.parse(&packet, true).unwrap();
+    perf.parse(&packet, false).unwrap();
 }
 
 #[cfg(test)]
@@ -1839,47 +1854,31 @@ mod tests {
         assert!(!perf.is_interested_packet(&packet));
     }
 
-    // TODO: fix this broken test (also fails in go code)
     #[test]
-    #[should_panic]
     fn meta_flow_perf_update() {
         let mut perf = TcpPerf::new(Arc::new(FlowPerfCounter::default()));
         _meta_flow_perf_update(&mut perf);
 
         let perf_data = PerfData {
             rtt_0: TimeStats {
-                sum: Timestamp::from_nanos(10),
-                max: Timestamp::from_nanos(2),
-                updated: true,
-                ..Default::default()
-            },
-            rtt_1: TimeStats {
-                sum: Timestamp::from_nanos(1),
-                max: Timestamp::from_nanos(1),
-                updated: true,
-                ..Default::default()
-            },
-            art_0: TimeStats {
-                sum: Timestamp::from_nanos(70),
-                max: Timestamp::from_nanos(70),
                 count: 1,
+                sum: Timestamp::from_secs(10),
+                max: Timestamp::from_secs(10),
                 updated: true,
                 ..Default::default()
             },
-            srt_0: TimeStats {
-                sum: Timestamp::from_nanos(16),
-                max: Timestamp::from_nanos(16),
-                count: 2,
-                updated: true,
-                ..Default::default()
-            },
-            srt_1: TimeStats {
+            rtt_1: TimeStats {
                 count: 1,
+                sum: Timestamp::from_secs(1),
+                max: Timestamp::from_secs(1),
                 updated: true,
                 ..Default::default()
             },
-            zero_win_count_0: 3,
+            rtt_full: Timestamp::from_secs(11),
+            zero_win_count_0: 2,
             zero_win_count_1: 5,
+            syn: 1,
+            synack: 1,
             updated: true,
             ..Default::default()
         };
@@ -1929,6 +1928,172 @@ mod tests {
         }
     }
 
+    #[test]
+    fn test_handshake_double_ack() {
+        let mut perf = TcpPerf::new(Arc::new(FlowPerfCounter::default()));
+
+        // SYN
+        let packet = MiniMetaPacket {
+            data_offset: 20,
+            flags: TcpFlags::SYN,
+            seq: 111,
+            ack: 0,
+            timestamp: 3333,
+            ..Default::default()
+        }
+        .into();
+        perf.parse(&packet, true).unwrap();
+
+        // SYN/ACK
+        let packet = MiniMetaPacket {
+            data_offset: 20,
+            flags: TcpFlags::SYN_ACK,
+            seq: 1111,
+            ack: 112,
+            timestamp: 3334,
+            ..Default::default()
+        }
+        .into();
+        perf.parse(&packet, false).unwrap();
+
+        // ACK c2s
+        let packet = MiniMetaPacket {
+            data_offset: 20,
+            flags: TcpFlags::ACK,
+            seq: 112,
+            ack: 1112,
+            timestamp: 3344,
+            ..Default::default()
+        }
+        .into();
+        perf.parse(&packet, true).unwrap();
+
+        // ACK c2s
+        let packet = MiniMetaPacket {
+            data_offset: 20,
+            flags: TcpFlags::ACK,
+            seq: 112,
+            ack: 1112,
+            timestamp: 3354,
+            ..Default::default()
+        }
+        .into();
+        perf.parse(&packet, true).unwrap();
+
+        println!("perf: {:?}", &perf.perf_data);
+        assert_eq!(
+            perf.perf_data.rtt_0.count, 2,
+            "rtt_0: {:?}",
+            perf.perf_data.rtt_0
+        );
+        assert_eq!(
+            perf.perf_data.rtt_0.max.as_secs(),
+            20,
+            "rtt_0: {:?}",
+            perf.perf_data.rtt_0
+        );
+        assert_eq!(
+            perf.perf_data.rtt_1.count, 1,
+            "rtt_1: {:?}",
+            perf.perf_data.rtt_1
+        );
+        assert_eq!(
+            perf.perf_data.rtt_1.max.as_secs(),
+            1,
+            "rtt_1: {:?}",
+            perf.perf_data.rtt_1
+        );
+        assert_eq!(
+            perf.perf_data.rtt_full.as_secs(),
+            21,
+            "rtt_full: {:?}",
+            perf.perf_data.rtt_full
+        );
+    }
+
+    #[test]
+    fn test_handshake_no_push() {
+        let mut perf = TcpPerf::new(Arc::new(FlowPerfCounter::default()));
+
+        // SYN
+        let packet = MiniMetaPacket {
+            data_offset: 20,
+            flags: TcpFlags::SYN,
+            seq: 111,
+            ack: 0,
+            timestamp: 3333,
+            ..Default::default()
+        }
+        .into();
+        perf.parse(&packet, true).unwrap();
+
+        // SYN/ACK
+        let packet = MiniMetaPacket {
+            data_offset: 20,
+            flags: TcpFlags::SYN_ACK,
+            seq: 1111,
+            ack: 112,
+            timestamp: 3334,
+            ..Default::default()
+        }
+        .into();
+        perf.parse(&packet, false).unwrap();
+
+        // ACK c2s
+        let packet = MiniMetaPacket {
+            data_offset: 20,
+            flags: TcpFlags::ACK,
+            seq: 112,
+            ack: 1112,
+            timestamp: 3344,
+            ..Default::default()
+        }
+        .into();
+        perf.parse(&packet, true).unwrap();
+
+        // ACK s2c
+        let packet = MiniMetaPacket {
+            data_offset: 20,
+            flags: TcpFlags::ACK,
+            seq: 1111,
+            ack: 112,
+            timestamp: 3354,
+            ..Default::default()
+        }
+        .into();
+        perf.parse(&packet, false).unwrap();
+
+        println!("perf: {:?}", &perf.perf_data);
+        assert_eq!(
+            perf.perf_data.rtt_0.count, 1,
+            "rtt_0: {:?}",
+            perf.perf_data.rtt_0
+        );
+        assert_eq!(
+            perf.perf_data.rtt_0.max.as_secs(),
+            10,
+            "rtt_0: {:?}",
+            perf.perf_data.rtt_0
+        );
+        assert_eq!(
+            perf.perf_data.rtt_1.count, 1,
+            "rtt_1: {:?}",
+            perf.perf_data.rtt_1
+        );
+        assert_eq!(
+            perf.perf_data.rtt_1.max.as_secs(),
+            1,
+            "rtt_1: {:?}",
+            perf.perf_data.rtt_1
+        );
+        assert_eq!(
+            perf.perf_data.rtt_full.as_secs(),
+            11,
+            "rtt_full: {:?}",
+            perf.perf_data.rtt_full
+        );
+    }
+
     fn update_test_helper<P: AsRef<Path>>(file: P, check_seq_list: bool) -> String {
         let mut output = String::new();