1#!/bin/ksh -p
2#
3# CDDL HEADER START
4#
5# This file and its contents are supplied under the terms of the
6# Common Development and Distribution License ("CDDL"), version 1.0.
7# You may only use this file in accordance with the terms of version
8# 1.0 of the CDDL.
9#
10# A full copy of the text of the CDDL should have accompanied this
11# source.  A copy of the CDDL is also available via the Internet at
12# http://www.illumos.org/license/CDDL.
13#
14# CDDL HEADER END
15#
16
17#
18# Copyright (c) 2020, George Amanakis. All rights reserved.
19#
20
21. $STF_SUITE/tests/functional/cache/cache.cfg
22. $STF_SUITE/tests/functional/cache/cache.kshlib
23
24#
25# DESCRIPTION:
26#	Looping around a cache device with l2arc_write_size exceeding
27#	the device size succeeds.
28#
29# STRATEGY:
30#	1. Create pool with a cache device.
31#	2. Set l2arc_write_max to a value larger than the cache device.
32#	3. Create a file larger than the cache device and random read
33#		for 10 sec.
34#	4. Verify that l2arc_write_max is set back to the default.
35#	5. Set l2arc_write_max to a value less than the cache device size but
36#		larger than the default (256MB).
37#	6. Record the l2_size.
38#	7. Random read for 1 sec.
39#	8. Record the l2_size again.
40#	9. If (6) <= (8) then we have not looped around yet.
41#	10. If (6) > (8) then we looped around. Break out of the loop and test.
42#	11. Destroy pool.
43#
44
45verify_runnable "global"
46
47command -v fio > /dev/null || log_unsupported "fio missing"
48
49log_assert "Looping around a cache device succeeds."
50
51function cleanup
52{
53	if poolexists $TESTPOOL ; then
54		destroy_pool $TESTPOOL
55	fi
56
57	log_must set_tunable32 L2ARC_WRITE_MAX $write_max
58	log_must set_tunable32 L2ARC_NOPREFETCH $noprefetch
59}
60log_onexit cleanup
61
62typeset write_max=$(get_tunable L2ARC_WRITE_MAX)
63typeset noprefetch=$(get_tunable L2ARC_NOPREFETCH)
64log_must set_tunable32 L2ARC_NOPREFETCH 0
65
66typeset VDEV="$VDIR/vdev.disk"
67typeset VDEV_SZ=$(( 4 * 1024 * 1024 * 1024 ))
68typeset VCACHE="$VDIR/vdev.cache"
69typeset VCACHE_SZ=$(( $VDEV_SZ / 2 ))
70
71typeset fill_mb=$(( floor($VDEV_SZ * 3 / 4 ) ))
72export DIRECTORY=/$TESTPOOL
73export NUMJOBS=4
74export RUNTIME=10
75export PERF_RANDSEED=1234
76export PERF_COMPPERCENT=66
77export PERF_COMPCHUNK=0
78export BLOCKSIZE=128K
79export SYNC_TYPE=0
80export DIRECT=1
81export FILE_SIZE=$(( floor($fill_mb / $NUMJOBS) ))
82
83log_must set_tunable32 L2ARC_WRITE_MAX $(( $VCACHE_SZ * 2 ))
84
85log_must truncate -s $VCACHE_SZ $VCACHE
86log_must truncate -s $VDEV_SZ $VDEV
87
88log_must zpool create -f $TESTPOOL $VDEV cache $VCACHE
89
90# Actually, this test relies on atime writes to force the L2 ARC discards
91log_must zfs set relatime=off $TESTPOOL
92
93log_must fio $FIO_SCRIPTS/mkfiles.fio
94log_must fio $FIO_SCRIPTS/random_reads.fio
95
96typeset write_max2=$(get_tunable L2ARC_WRITE_MAX)
97
98log_must test $write_max2 -eq $write_max
99
100log_must set_tunable32 L2ARC_WRITE_MAX $(( 256 * 1024 * 1024 ))
101export RUNTIME=1
102
103typeset do_once=true
104while $do_once || [[ $l2_size1 -le $l2_size2 ]]; do
105	typeset l2_size1=$(get_arcstat l2_size)
106	log_must fio $FIO_SCRIPTS/random_reads.fio
107	typeset l2_size2=$(get_arcstat l2_size)
108	do_once=false
109done
110
111log_must test $l2_size1 -gt $l2_size2
112
113log_must zpool destroy $TESTPOOL
114
115log_pass "Looping around a cache device succeeds."
116