def flush_cache(cache_id):
casadm.flush(cache_id=cache_id)
sync()
casadm.reset_counters(cache_id=cache_id)
stats = casadm_parser.get_statistics(cache_id=cache_id, filter=[StatsFilter.blk])
for key, value in stats.items():
assert value.get_value(Unit.Blocks4096) == 0
def test_write_fetch_partial_misses(cache_mode, cache_line_size):
"""
title: No caching of partial write miss operations
description: |
Validate CAS ability to not cache entire cache line size for
partial write miss operations
pass_criteria:
- Appropriate number of write partial misses, write hits and writes to cache
in cache statistics
- Appropriate number of writes to cache in iostat
"""
pattern = f"0x{uuid.uuid4().hex}"
io_size = Size(600, Unit.MebiByte)
with TestRun.step("Prepare devices."):
cache_disk = TestRun.disks['cache']
core_disk = TestRun.disks['core']
core_disk.create_partitions([io_size + Size(1, Unit.MebiByte)])
core_part = core_disk.partitions[0]
with TestRun.step("Fill core partition with pattern."):
cache_mode_traits = CacheMode.get_traits(cache_mode)
if CacheModeTrait.InsertRead in cache_mode_traits:
run_fio(target=core_part.path,
operation_type=ReadWrite.write,
blocksize=Size(4, Unit.KibiByte),
io_size=io_size,
verify=True,
pattern=pattern)
else:
TestRun.LOGGER.info(f"Skipped for {cache_mode} cache mode.")
with TestRun.step("Start cache and add core."):
cache = casadm.start_cache(cache_disk, cache_mode, cache_line_size)
Udev.disable()
core = cache.add_core(core_part)
with TestRun.step("Cache half of file."):
operation_type = ReadWrite.read if CacheModeTrait.InsertRead in cache_mode_traits \
else ReadWrite.write
run_fio(target=core.path,
operation_type=operation_type,
skip=cache_line_size.value,
blocksize=cache_line_size.value,
io_size=io_size,
verify=True,
pattern=pattern)
if CacheModeTrait.InsertRead not in cache_mode_traits:
cache.flush_cache()
casadm.reset_counters(cache.cache_id, core.core_id)
with TestRun.step("Run writes to CAS device using fio."):
io_stats_before_io = cache_disk.get_io_stats()
blocksize = cache_line_size.value / 2 * 3
skip_size = cache_line_size.value / 2
run_fio(target=core.path,
operation_type=ReadWrite.write,
skip=skip_size,
blocksize=blocksize,
io_size=io_size)
with TestRun.step(
"Verify CAS statistics for partial misses, write hits and writes to cache."
):
check_statistics(cache=cache,
blocksize=blocksize,
skip_size=skip_size,
io_size=io_size,
partial_misses=True)
with TestRun.step(
"Verify number of writes to cache device using iostat. Shall be 0.75 of "
f"io size ({str(io_size * 0.75)}) + metadata for cache mode with write "
f"insert feature."):
check_io_stats(cache_disk=cache_disk,
cache=cache,
io_stats_before=io_stats_before_io,
io_size=io_size,
blocksize=blocksize,
skip_size=skip_size)
def reset_counters(self):
return casadm.reset_counters(self.cache_id, self.core_id)