Add the protocol-comparison module

protocol-comparison/src/test/java/com/ankurm/protocols/Bench.java

@@ -0,0 +1,29 @@
+package com.ankurm.protocols;
+
+import java.util.Arrays;
+
+/** Latency bookkeeping, kept in one place so the three protocols are measured identically. */
+final class Bench {
+
+    private final long[] nanos;
+    private int i;
+
+    Bench(int n) {
+        this.nanos = new long[n];
+    }
+
+    void record(long ns) {
+        nanos[i++] = ns;
+    }
+
+    /** p50, p99 and mean in microseconds, plus calls per second derived from the mean. */
+    String summary(String label) {
+        long[] sorted = Arrays.copyOf(nanos, i);
+        Arrays.sort(sorted);
+        double p50 = sorted[(int) (sorted.length * 0.50)] / 1000.0;
+        double p99 = sorted[(int) (sorted.length * 0.99)] / 1000.0;
+        double mean = Arrays.stream(sorted).average().orElse(0) / 1000.0;
+        return String.format("%-12s n=%-6d p50=%8.1f us  p99=%9.1f us  mean=%8.1f us  ~%,.0f calls/s",
+                label, sorted.length, p50, p99, mean, 1_000_000.0 / mean);
+    }
+}