Increase L2ARC write rate and headroom
[zfs.git] / cmd / zvol_wait
blob0b2a8a3e60c3fdebd2ba85f772d6563041e83c83
1 #!/bin/sh
3 count_zvols() {
4 if [ -z "$zvols" ]; then
5 echo 0
6 else
7 echo "$zvols" | wc -l
8 fi
11 filter_out_zvols_with_links() {
12 echo "$zvols" | tr ' ' '+' | while read -r zvol; do
13 if ! [ -L "/dev/zvol/$zvol" ]; then
14 echo "$zvol"
16 done | tr '+' ' '
19 filter_out_deleted_zvols() {
20 OIFS="$IFS"
21 IFS="
23 # shellcheck disable=SC2086
24 zfs list -H -o name $zvols 2>/dev/null
25 IFS="$OIFS"
28 list_zvols() {
29 read -r default_volmode < /sys/module/zfs/parameters/zvol_volmode
30 zfs list -t volume -H -o \
31 name,volmode,receive_resume_token,redact_snaps,keystatus |
32 while IFS=" " read -r name volmode token redacted keystatus; do # IFS=\t here!
34 # /dev links are not created for zvols with volmode = "none",
35 # redacted zvols, or encrypted zvols for which the key has not
36 # been loaded.
37 [ "$volmode" = "none" ] && continue
38 [ "$volmode" = "default" ] && [ "$default_volmode" = "3" ] &&
39 continue
40 [ "$redacted" = "-" ] || continue
41 [ "$keystatus" = "unavailable" ] && continue
43 # We also ignore partially received zvols if it is
44 # not an incremental receive, as those won't even have a block
45 # device minor node created yet.
46 if [ "$token" != "-" ]; then
48 # Incremental receives create an invisible clone that
49 # is not automatically displayed by zfs list.
50 if ! zfs list "$name/%recv" >/dev/null 2>&1; then
51 continue
54 echo "$name"
55 done
58 zvols=$(list_zvols)
59 zvols_count=$(count_zvols)
60 if [ "$zvols_count" -eq 0 ]; then
61 echo "No zvols found, nothing to do."
62 exit 0
65 echo "Testing $zvols_count zvol links"
67 outer_loop=0
68 while [ "$outer_loop" -lt 20 ]; do
69 outer_loop=$((outer_loop + 1))
71 old_zvols_count=$(count_zvols)
73 inner_loop=0
74 while [ "$inner_loop" -lt 30 ]; do
75 inner_loop=$((inner_loop + 1))
77 zvols="$(filter_out_zvols_with_links)"
79 zvols_count=$(count_zvols)
80 if [ "$zvols_count" -eq 0 ]; then
81 echo "All zvol links are now present."
82 exit 0
84 sleep 1
85 done
87 echo "Still waiting on $zvols_count zvol links ..."
89 # Although zvols should normally not be deleted at boot time,
90 # if that is the case then their links will be missing and
91 # we would stall.
93 if [ "$old_zvols_count" -eq "$zvols_count" ]; then
94 echo "No progress since last loop."
95 echo "Checking if any zvols were deleted."
97 zvols=$(filter_out_deleted_zvols)
98 zvols_count=$(count_zvols)
100 if [ "$old_zvols_count" -ne "$zvols_count" ]; then
101 echo "$((old_zvols_count - zvols_count)) zvol(s) deleted."
104 if [ "$zvols_count" -ne 0 ]; then
105 echo "Remaining zvols:"
106 echo "$zvols"
107 else
108 echo "All zvol links are now present."
109 exit 0
114 # zvol_count made some progress - let's stay in this loop.
116 if [ "$old_zvols_count" -gt "$zvols_count" ]; then
117 outer_loop=$((outer_loop - 1))
119 done
121 echo "Timed out waiting on zvol links"
122 exit 1