open-cas-linux/test/functional/tests/io/trim/test_trim_eviction.py
Katarzyna Lapinska 0b455ada64 Add test verifying if trim request do not cause eviction on CAS device
Signed-off-by: Katarzyna Lapinska <katarzyna.lapinska@intel.com>
2020-08-17 14:30:08 +02:00

89 lines
3.6 KiB
Python

#
# Copyright(c) 2020 Intel Corporation
# SPDX-License-Identifier: BSD-3-Clause-Clear
#
import os
import pytest
from api.cas import casadm
from api.cas.cache_config import CacheMode, CacheLineSize, CleaningPolicy
from core.test_run import TestRun
from storage_devices.disk import DiskTypeSet, DiskType, DiskTypeLowerThan
from test_tools import fs_utils
from test_tools.ddrescue import Ddrescue
from test_tools.disk_utils import Filesystem
from test_utils import os_utils
from test_utils.os_utils import Udev
from test_utils.size import Size, Unit
@pytest.mark.require_disk("cache", DiskTypeSet([DiskType.optane, DiskType.nand, DiskType.sata]))
@pytest.mark.require_disk("core", DiskTypeLowerThan("cache"))
@pytest.mark.parametrizex("cache_mode", CacheMode)
@pytest.mark.parametrizex("cache_line_size", CacheLineSize)
@pytest.mark.parametrizex("filesystem", [Filesystem.ext4, Filesystem.xfs])
@pytest.mark.parametrizex("cleaning", [CleaningPolicy.alru, CleaningPolicy.nop])
def test_trim_eviction(cache_mode, cache_line_size, filesystem, cleaning):
"""
title: Test verifying if trim requests do not cause eviction on CAS device.
description: |
When trim requests enabled and files are being added and removed from CAS device,
there is no eviction (no reads from cache).
pass_criteria:
- Reads from cache device are the same before and after removing test file.
"""
mount_point = "/mnt"
test_file_path = os.path.join(mount_point, "test_file")
with TestRun.step("Prepare devices."):
cache_disk = TestRun.disks['cache']
cache_disk.create_partitions([Size(1, Unit.GibiByte)])
cache_dev = cache_disk.partitions[0]
core_disk = TestRun.disks['core']
core_disk.create_partitions([Size(1, Unit.GibiByte)])
core_dev = core_disk.partitions[0]
with TestRun.step("Start cache on device supporting trim and add core."):
cache = casadm.start_cache(cache_dev, cache_mode, cache_line_size)
cache.set_cleaning_policy(cleaning)
Udev.disable()
core = cache.add_core(core_dev)
with TestRun.step("Create filesystem on CAS device and mount it."):
core.create_filesystem(filesystem)
core.mount(mount_point, ["discard"])
with TestRun.step("Create random file using ddrescue."):
test_file = fs_utils.create_random_test_file(test_file_path, core_dev.size * 0.9)
create_file_with_ddrescue(core_dev, test_file)
with TestRun.step("Remove file and create a new one."):
cache_iostats_before = cache_dev.get_io_stats()
test_file.remove()
os_utils.sync()
os_utils.drop_caches()
create_file_with_ddrescue(core_dev, test_file)
with TestRun.step("Check using iostat that reads from cache did not occur."):
cache_iostats_after = cache_dev.get_io_stats()
reads_before = cache_iostats_before.sectors_read
reads_after = cache_iostats_after.sectors_read
if reads_after != reads_before:
TestRun.fail(f"Number of reads from cache before and after removing test file "
f"differs. Reads before: {reads_before}, reads after: {reads_after}.")
else:
TestRun.LOGGER.info(
"Number of reads from cache before and after removing test file is the same.")
def create_file_with_ddrescue(core_dev, test_file):
ddrescue = Ddrescue() \
.block_size(Size(1, Unit.Blocks4096)) \
.size(core_dev.size * 0.9) \
.synchronous() \
.source("/dev/urandom") \
.destination(test_file.full_path)
ddrescue.run()