Add histogram for diff ts measures

packet-exchange/src/common.h

@@ -26,6 +26,7 @@
 #define MAX_KERNEL_LATENCY 1000
 #define MAX_RTT 1000
 #define MAX_JITTER 1000
+#define MAX_DIFF_TS 1000
 
 #define MAX_BUFFER_SIZE 1024
 

packet-exchange/src/server.c

@@ -65,6 +65,7 @@ static void sighand(int sig_num);
 
 static uint64_t kernel_latency_hist[MAX_KERNEL_LATENCY];
 static uint64_t jitter_hist[MAX_JITTER];
+static uint64_t diff_ts_hist[MAX_DIFF_TS];
 static main_param_t main_params;
 static thread_param_t thread_params;
 static ingress_param_t ingress_params;
@@ -84,6 +85,7 @@ static pthread_cond_t emit_signal_ts_received;
 static int64_t min_diff_ts = INT_MAX;
 static int64_t max_diff_ts = 0;
 static int64_t avg_diff_ts = 0;
+static uint64_t high_diff_ts = 0;
 
 static char ts_tracemark_buf[64];
 
@@ -264,6 +266,14 @@ static void *tsn_thread(void *p) {
         max_diff_ts = _max_(diff_us, max_diff_ts);
         avg_diff_ts = (avg_diff_ts * ingress_stats.packets_received + diff_us) / (ingress_stats.packets_received + 1);
 
+        // Histogram
+        if (enable_histograms) {
+          if (diff_us > ((int)MAX_DIFF_TS) || diff_us < 0)
+            high_diff_ts++;
+          else
+            diff_ts_hist[diff_us]++;
+        }
+
         // If the latency hits the tracing threshold, stop tracing
         if (main_params.enable_tracing &&
             (max_diff_ts > ((int64_t)thread_params.latency_threshold))) {
@@ -400,6 +410,7 @@ int main(int argc, char *argv[]) {
   if (enable_histograms) {
     memset(kernel_latency_hist, 0, sizeof(kernel_latency_hist));
     memset(jitter_hist, 0, sizeof(jitter_hist));
+    memset(diff_ts_hist, 0, sizeof(diff_ts_hist));
   }
 
   // Enable ftrace
@@ -481,6 +492,21 @@ static void print_histograms() {
   duration_hour = duration / NSEC_PER_SEC / 3600;
   duration_minutes = duration / NSEC_PER_SEC / 60 - duration_hour * 60;
 
+  if (thread_params.enable_diff_ts) {
+    printf("# RX latency histogram\n");
+
+    max_latency = histogram_max(diff_ts_hist, MAX_DIFF_TS - 1);
+
+    for (int j = 0; j < max_latency; j++)
+      printf(" %06d %015" PRIi64 "\n", j, diff_ts_hist[j]);
+
+    printf(
+        "# Duration: %dh%d\n"
+        "# Lost packets: %" PRIu64 "\n",
+        duration_hour, duration_minutes, high_diff_ts);
+  }
+  else {
+
     max_jitter = histogram_max(jitter_hist, MAX_JITTER - 1);
     min_jitter = histogram_min(jitter_hist, MAX_JITTER - 1);
 
@@ -510,6 +536,7 @@ static void print_histograms() {
         "# Lost packets: %" PRIu64 "\n",
         MAX_JITTER / 2 - min_jitter, duration_hour, duration_minutes,
         ingress_stats.high_jitter);
+  }
 
 }