feat: save network perf tests data

Save logs and json files for network perf tests.

Signed-off-by: Egor Lazarchuk <yegorlz@amazon.co.uk>

Author: ShadowCurse

tests/integration_tests/performance/test_network_ab.py

@@ -2,7 +2,9 @@
 # SPDX-License-Identifier: Apache-2.0
 """Tests the network latency of a Firecracker guest."""
 
+import json
 import re
+from pathlib import Path
 
 import pytest
 
@@ -95,6 +97,7 @@ def test_network_tcp_throughput(
     payload_length,
     mode,
     metrics,
+    test_output_dir,
 ):
     """
     Iperf between guest and host in both directions for TCP workload.
@@ -133,4 +136,16 @@ def test_network_tcp_throughput(
     )
     data = test.run_test(network_microvm.vcpus_count + 2)
 
+    cpu_load_path = Path(test_output_dir / "cpu_load.json")
+    with open(cpu_load_path, "w", encoding="utf-8") as f:
+        json.dump(data["cpu_load_raw"], f)
+    for i, g2h in enumerate(data["g2h"]):
+        path = Path(test_output_dir / f"g2h_{i}.json")
+        with open(path, "w", encoding="utf-8") as f:
+            json.dump(g2h, f)
+    for i, h2g in enumerate(data["h2g"]):
+        path = Path(test_output_dir / f"h2g_{i}.json")
+        with open(path, "w", encoding="utf-8") as f:
+            json.dump(h2g, f)
+
     emit_iperf3_metrics(metrics, data, warmup_sec)