| #!/bin/ksh -p |
| # |
| # CDDL HEADER START |
| # |
| # This file and its contents are supplied under the terms of the |
| # Common Development and Distribution License ("CDDL"), version 1.0. |
| # You may only use this file in accordance with the terms of version |
| # 1.0 of the CDDL. |
| # |
| # A full copy of the text of the CDDL should have accompanied this |
| # source. A copy of the CDDL is also available via the Internet at |
| # http://www.illumos.org/license/CDDL. |
| # |
| # CDDL HEADER END |
| # |
| |
| # |
| # Copyright (c) 2020, George Amanakis. All rights reserved. |
| # |
| |
| . $STF_SUITE/include/libtest.shlib |
| . $STF_SUITE/tests/functional/l2arc/l2arc.cfg |
| |
| # |
| # DESCRIPTION: |
| # l2arc_mfuonly does not cache MRU buffers |
| # |
| # STRATEGY: |
| # 1. Set l2arc_mfuonly=yes |
| # 2. Create pool with a cache device. |
| # 3. Create a random file in that pool, smaller than the cache device |
| # and random read for 10 sec. |
| # 4. Export and re-import the pool. This is necessary as some MFU ghost |
| # buffers with prefetch status may transition to MRU eventually. |
| # By re-importing the pool the l2 arcstats reflect the ARC state |
| # of L2ARC buffers upon their caching in L2ARC. |
| # 5. Verify l2arc_mru_asize is 0. |
| # |
| |
| verify_runnable "global" |
| |
| log_assert "l2arc_mfuonly does not cache MRU buffers." |
| |
| function cleanup |
| { |
| if poolexists $TESTPOOL ; then |
| destroy_pool $TESTPOOL |
| fi |
| |
| log_must set_tunable32 L2ARC_NOPREFETCH $noprefetch |
| log_must set_tunable32 L2ARC_MFUONLY $mfuonly |
| log_must set_tunable32 PREFETCH_DISABLE $zfsprefetch |
| } |
| log_onexit cleanup |
| |
| # L2ARC_NOPREFETCH is set to 1 as some prefetched buffers may |
| # transition to MRU. |
| typeset noprefetch=$(get_tunable L2ARC_NOPREFETCH) |
| log_must set_tunable32 L2ARC_NOPREFETCH 1 |
| |
| typeset mfuonly=$(get_tunable L2ARC_MFUONLY) |
| log_must set_tunable32 L2ARC_MFUONLY 1 |
| |
| typeset zfsprefetch=$(get_tunable PREFETCH_DISABLE) |
| log_must set_tunable32 PREFETCH_DISABLE 1 |
| |
| typeset fill_mb=800 |
| typeset cache_sz=$(( 1.4 * $fill_mb )) |
| export FILE_SIZE=$(( floor($fill_mb / $NUMJOBS) ))M |
| |
| log_must truncate -s ${cache_sz}M $VDEV_CACHE |
| |
| typeset log_blk_start=$(get_arcstat l2_log_blk_writes) |
| |
| log_must zpool create -f $TESTPOOL $VDEV cache $VDEV_CACHE |
| |
| log_must fio $FIO_SCRIPTS/mkfiles.fio |
| log_must fio $FIO_SCRIPTS/random_reads.fio |
| |
| log_must zpool export $TESTPOOL |
| log_must zpool import -d $VDIR $TESTPOOL |
| |
| # Regardless of l2arc_noprefetch, some MFU buffers might be evicted |
| # from ARC, accessed later on as prefetches and transition to MRU as |
| # prefetches. |
| # If accessed again they are counted as MRU and the l2arc_mru_asize arcstat |
| # will not be 0 (mentioned also in zfs.4) |
| # For the purposes of this test we mitigate this by disabling (predictive) |
| # ZFS prefetches with zfs_prefetch_disable=1. |
| log_must test $(get_arcstat l2_mru_asize) -eq 0 |
| |
| log_must zpool destroy -f $TESTPOOL |
| |
| log_pass "l2arc_mfuonly does not cache MRU buffers." |