Add nbdssl support

tests/perf/test_compare.py

@@ -0,0 +1,88 @@
+# Copyright 2026 Cloudbase Solutions Srl
+# All Rights Reserved.
+
+"""Compare openvixdisklib and native VDDK I/O throughput against the lab."""
+
+from __future__ import annotations
+
+import time
+from typing import Any, Optional
+
+from openvixdisklib import openvixdisklib as open_vix
+from tests.integration import vixdisklib
+from tests.integration.base import LabEnv, SECTOR_SIZE, pattern_bytes
+
+_SIZES = (
+    ("64KiB", 64 * 1024),
+    ("129 sectors", 129 * SECTOR_SIZE),
+    ("32MiB", 32 * 1024 * 1024),
+)
+
+
+def _connect_extra(lab: LabEnv, module: Any) -> Optional[dict[str, Any]]:
+    """Return extra ``connect`` kwargs needed by ``module``."""
+    if module is open_vix:
+        return {"allow_untrusted": lab.allow_untrusted}
+    return None
+
+
+def _time_write_read(
+        lab: LabEnv,
+        module: Any,
+        payload: bytes) -> tuple[float, float]:
+    """Write ``payload`` at sector 0, read it back, and return durations."""
+    n_sectors = len(payload) // SECTOR_SIZE
+    handle = module.VixDiskLibHandle(
+        vixdisklib_compatibility_version="8.0",
+        config_path=None)
+    write_buf = module.get_buffer(len(payload))
+    read_buf = module.get_buffer(len(payload))
+    write_buf[:len(payload)] = payload
+    kwargs = lab.vixdisklib_connect_kwargs(_connect_extra(lab, module))
+    with handle.connect(**kwargs) as conn:
+        with handle.open(conn, lab.disk_path, flags=0) as disk:
+            started = time.perf_counter()
+            handle.write(disk, 0, n_sectors, write_buf)
+            write_s = time.perf_counter() - started
+            read_buf[:len(payload)] = b"\xa5" * len(payload)
+            started = time.perf_counter()
+            handle.read(disk, 0, n_sectors, read_buf)
+            read_s = time.perf_counter() - started
+    assert read_buf.raw[:len(payload)] == payload
+    return write_s, read_s
+
+
+def _mib_per_s(nbytes: int, seconds: float) -> float:
+    if seconds <= 0:
+        return float("inf")
+    return (nbytes / (1024 * 1024)) / seconds
+
+
+class TestCompare:
+    def test_write_read_throughput(self, lab: LabEnv, vddk: None) -> None:
+        """Time matching write/read sizes on VDDK and openvixdisklib."""
+        libraries = (
+            ("vddk", vixdisklib),
+            ("openvixdisklib", open_vix),
+        )
+        rows: list[tuple[str, str, float, float, float, float]] = []
+        for label, nbytes in _SIZES:
+            payload = pattern_bytes(nbytes, f"PERF-{label}-".encode())
+            for name, module in libraries:
+                write_s, read_s = _time_write_read(lab, module, payload)
+                rows.append((
+                    label,
+                    name,
+                    write_s,
+                    read_s,
+                    _mib_per_s(nbytes, write_s),
+                    _mib_per_s(nbytes, read_s),
+                ))
+        print()
+        print(
+            f"{'size':<14} {'library':<16} {'write_s':>10} {'read_s':>10} "
+            f"{'write_MiB/s':>12} {'read_MiB/s':>12}")
+        for label, name, write_s, read_s, write_r, read_r in rows:
+            print(
+                f"{label:<14} {name:<16} {write_s:10.3f} {read_s:10.3f} "
+                f"{write_r:12.1f} {read_r:12.1f}")