Add verify_no_swap_on_osdisk case

Author: lubaihua33

lisa/tools/swap.py

@@ -1,12 +1,17 @@
 # Copyright (c) Microsoft Corporation.
 # Licensed under the MIT license.
 import re
-from typing import Optional, Type
+from typing import List, Optional, Type
 
+from lisa.base_tools import Cat
 from lisa.executable import Tool
 from lisa.tools.lsblk import Lsblk
 from lisa.tools.rm import Rm
-from lisa.util import find_patterns_in_lines
+from lisa.util import (
+    LisaException,
+    find_patterns_groups_in_lines,
+    find_patterns_in_lines,
+)
 
 
 class SwapOn(Tool):
@@ -28,6 +33,14 @@ def command(self) -> str:
 
 
 class Swap(Tool):
+    # Filename       Type         Size      Used      Priority
+    # /dev/sdb2      partition    1020      0          -2
+    # /swapfile      file         200M     15M         -3
+    # /mnt/swapfile  file         2097148   0          -4
+    _SWAPS_PATTERN = re.compile(
+        r"(?P<filename>\S+)\s+(?P<type>\S+)\s+(?P<size>\d+)\w?\s+(?P<used>\d+)\w?\s+(?P<priority>-?\d+)"  # noqa: E501
+    )
+
     @property
     def command(self) -> str:
         raise NotImplementedError()
@@ -53,6 +66,26 @@ def is_swap_enabled(self) -> bool:
         lsblk = self.node.tools[Lsblk].run().stdout
         return "SWAP" in lsblk
 
+    def get_swap_partitions(self) -> List[str]:
+        # run 'cat /proc/swaps' or 'swapon -s' and parse the output
+        # The output is in the following format:
+        # <Filename> <Type> <Size> <Used> <Priority>
+        cat = self.node.tools[Cat]
+        swap_result = cat.run("/proc/swaps", shell=True, sudo=True)
+        if swap_result.exit_code != 0:
+            # Try another way to get swap information
+            swap_result = self.node.tools[SwapOn].run("-s")
+            if swap_result.exit_code != 0:
+                raise LisaException("Failed to get swap information")
+
+        output = swap_result.stdout
+        swap_parts: List[str] = []
+        swap_entries = find_patterns_groups_in_lines(output, [self._SWAPS_PATTERN])[0]
+        for swap_entry in swap_entries:
+            if swap_entry["type"] == "partition":
+                swap_parts.append(swap_entry["filename"])
+        return swap_parts
+
     def create_swap(
         self, path: str = "/tmp/swap", size: str = "1M", count: int = 1024
     ) -> None:
@@ -84,3 +117,19 @@ def is_swap_enabled(self) -> bool:
             return True
 
         return False
+
+    def get_swap_partitions(self) -> List[str]:
+        # run 'swapinfo -k' and parse the output
+        # The output is in the following format:
+        # <Device> <1K-blocks> <Used> <Avail> <Capacity>
+        swap_result = self.run("-k")
+        if swap_result.exit_code != 0:
+            raise LisaException("Failed to get swap information")
+
+        output = swap_result.stdout
+        swap_parts: List[str] = []
+        swap_entries = find_patterns_groups_in_lines(output, [self._SWAP_ENTRIES])[0]
+        # FreeBSD doesn't have swap files, only partitions
+        for swap_entry in swap_entries:
+            swap_parts.append(swap_entry["device"])
+        return swap_parts

microsoft/testsuites/core/azure_image_standard.py

@@ -40,7 +40,7 @@
 from lisa.sut_orchestrator import AZURE, HYPERV, READY
 from lisa.sut_orchestrator.azure.features import AzureDiskOptionSettings
 from lisa.sut_orchestrator.azure.tools import Waagent
-from lisa.tools import Cat, Dmesg, Journalctl, Ls, Lsblk, Lscpu, Pgrep, Ssh
+from lisa.tools import Cat, Dmesg, Journalctl, Ls, Lsblk, Lscpu, Pgrep, Ssh, Swap
 from lisa.util import (
     LisaException,
     PassedException,
@@ -1460,6 +1460,55 @@ def verify_omi_version(self, node: Node) -> None:
                     f"{minimum_secure_version} to prevent OMIGOD vulnerabilities."
                 ) from e
 
+    @TestCaseMetadata(
+        description="""
+        This test verifies that there is no swap partition on the OS disk.
+
+        Azure's policy 200.3.3 Linux:
+        No swap partition on the OS disk. Swap can be requested for creation on the
+        local resource disk by the Linux Agent. It is recommended that a single root
+        partition is created for the OS disk.
+
+        There should be no Swap Partition on OS Disk. OS disk has IOPS limit. When
+        memory pressure causes swapping, IOPS limit may be reached easily and cause VM
+        performance to go down disastrously, because aside from memory issues in now
+        also has IO issues.
+
+        Steps:
+        1. Use 'cat /proc/swaps' or 'swapon -s' list all swap devices
+            Note: For FreeBSD, use 'swapinfo -k'.
+        2. Use 'lsblk' to identify the OS disk and get all the partitions
+            Note: For FreeBSD, if there is no lsblk, install it and run the command
+        3. Verify that no swap partition exists on the OS disk
+        """,
+        priority=1,
+        requirement=simple_requirement(supported_platform_type=[AZURE]),
+    )
+    def verify_no_swap_on_osdisk(self, node: Node) -> None:
+        swap_tool = node.tools[Swap]
+        swap_parts = swap_tool.get_swap_partitions()
+        if not swap_parts:
+            return
+        node.log.info(f"Swap partitions: {swap_parts}")
+
+        lsblk = node.tools[Lsblk]
+        os_disk = lsblk.find_disk_by_mountpoint("/")
+        # e.g. os_disk_partitions: ['sda1', 'sda2']
+        os_disk_partitions = [part.name for part in os_disk.partitions]
+        node.log.info(f"OS disk partitions: {os_disk_partitions}")
+
+        for swap_part in swap_parts:
+            for os_part in os_disk_partitions:
+                if os_part in swap_part:
+                    raise LisaException(
+                        f"Swap partition '{swap_part}' found on OS disk. There should"
+                        "  be no Swap Partition on OS Disk. OS disk has IOPS limit. "
+                        "When memory pressure causes swapping, IOPS limit may be "
+                        "reached easily and cause VM performance to go down "
+                        "disastrously, because aside from memory issues in now also "
+                        "has IO issues."
+                    )
+
     def _verify_version_by_pattern_value(
         self,
         node: Node,