1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
|
#!/bin/sh
#
# swapmon - add / remove swap as needed
#
# Copyright (C) 2010 Alexander Kuehn. All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
#
CONFIG=%%PREFIX%%/etc/swapmonrc
VERSION="1.5"
if [ -r "${CONFIG}" ]
then . "${CONFIG}"
fi
# where to create swapfiles
: ${SM_HOME=/usr/.swap}
# if the swap usage is higher than that (percentage) new swap will be added
: ${SWAP_HIGH=75}
# if the swap usage is lower than that then a previously added swapfile will be removed
: ${SWAP_LOW=45}
# if swap is running low we will increase the swapspace by this many percent
: ${SWAP_STEP=$(( 100 - ${SWAP_HIGH} ))}
# if running as daemon how long to wait between checks
: ${DELAY=30}
# if running as daemon where to log messages
: ${LOGGER=/usr/bin/logger}
# if running as daemon where to put pidfile
: ${PIDFILE=/var/run/swapmon.pid}
# if no swap is configured create a swapfile with this size
: ${SWAP_MIN=256}
LOCKF=$SM_HOME/lock
SWAPFILE=$SM_HOME/swap.XXXX
SWAPLIST=$SM_HOME/swapfiles
SWAPDEF=$SM_HOME/swap.def
MKTEMP=/usr/bin/mktemp
TRUNCATE=/usr/bin/truncate
TOUCH=/usr/bin/touch
CHMOD=/bin/chmod
MDCONFIG=/sbin/mdconfig
SWAPON=/sbin/swapon
SWAPOFF=/sbin/swapoff
SWAPCTL=/sbin/swapctl
RM=/bin/rm
SED=/usr/bin/sed
PERM=600
UID=$(/usr/bin/id -u)
GID=$(/usr/bin/id -g)
umask 0077
# a few sanity checks to see if we can do our work
if [ $UID -gt 0 ]
then echo "I'm not running as root (uid=0) this probably wont work."
# exit 1
fi
if [ \! -d ${SM_HOME} ]
then /bin/mkdir -p ${SM_HOME} || { echo "Error creating ${SM_HOME}!" ; exit 1; }
fi
$TOUCH ${SWAPLIST} || { echo "Can't write to ${SWAPLIST} aborting." ; exit 1; }
# add a 1MB swapfile to check if we have the permissions to do so
NSWAP=$($MKTEMP ${SWAPFILE})
$TRUNCATE -s 1M "${NSWAP}" || { echo "Error creating swapfile ${NSWAP}, aborting." ; exit 1; }
$CHMOD ${PERM} "${NSWAP}"
MDEV=$($MDCONFIG -a -t vnode -f "${NSWAP}")
if [ -n "$MDEV" ]
then
$SWAPON /dev/${MDEV} || { echo "error activating swapdevice /dev/${MDEV}."; exit 1; }
$SWAPOFF "/dev/${MDEV}"
$MDCONFIG -d -u ${MDEV} >/dev/null
$RM -f "${NSWAP}"
else
echo "error configuring memory disk ($MDCONFIG -a -t vnode -f \"${NSWAP}\")"
$RM -f "${NSWAP}"
exit
fi
# delete leftover swapfiles
find $SM_HOME -maxdepth 1 -name $(echo ${SWAPFILE##*/}|tr X \?) -type f \
-perm ${PERM} -user $UID -group $GID -exec $RM -fv "{}" \;
if [ ${SWAP_LOW} -ge $(( $(($SWAP_HIGH * 100)) / $((100 + $SWAP_STEP)) )) ]
then echo "SWAP_LOW(${SWAP_LOW}) schould be lower than $(( $(($SWAP_HIGH * 100)) / $((100 + $SWAP_STEP)) )) to be useful."
echo "Swapmon $VERSION."
exit 1
fi
# if there is no swap configured, add some
add_def_swap()
{
SWAPCTLSK=$($SWAPCTL -sk)
SWAPTOTAL=${SWAPCTLSK#* }
SWAPTOTAL=${SWAPTOTAL% *}
if [ "$SWAPTOTAL" -eq 0 ]
then
if [ "${SWAP_MIN}" -gt 0 ]
then
if [ -e "${SWAPDEF}" ] # if the file already exists
then if [ -f "${SWAPDEF}" -a \! -h "${SWAPDEF}"] # is it a regular file and no symlink?
then $RM -f "${SWAPDEF}"
else echo "Error: swapfile ${SWAPDEF} is not a regular file, aborting." ; exit 1;
fi
fi
$TRUNCATE -s ${SWAP_MIN}M "${SWAPDEF}" || { echo "Error creating swapfile ${SWAPDEF}, aborting." ; exit 1; }
$CHMOD $PERM "${SWAPDEF}"
MDEV=$($MDCONFIG -a -t vnode -f "${SWAPDEF}")
if [ -n "$MDEV" ]
then
$SWAPON /dev/${MDEV} || { echo "error activating swapdevice /dev/${MDEV}."; exit 1; }
echo "swapmon$VERSION[$$] Activated swapfile ${SWAPDEF} as there was no swap configured!"|$LOGGER
else
echo "error configuring memory disk ($MDCONFIG -a -t vnode -f \"${SWAPDEF}\")"
$RM -f "${SWAPDEF}"
exit 1
fi
else
echo "No swap configured, SWAP_MIN set to $SWAP_MIN - aborting."
exit 1
fi
fi
}
check_swap()
{
SWAPCTLSK=$($SWAPCTL -sk)
SWAPTOTAL=${SWAPCTLSK#* }
SWAPTOTAL=${SWAPTOTAL% *}
SWAPUSAGE=$(( ${SWAPCTLSK##* } * 100 / $SWAPTOTAL ))
if [ ${SWAPUSAGE} -gt ${SWAP_HIGH} ]
then NSWAP=$($MKTEMP ${SWAPFILE})
BLOCKS=$(( $(( ${SWAPTOTAL} * ${SWAP_STEP} +1023)) / 102400 ))
# make sure we can write to the swaplist
$TOUCH "${SWAPLIST}" || { echo "swapmon$VERSION[$$] Error modifying ${SWAPLIST} exiting."|$LOGGER; exit 1; }
$TRUNCATE -s ${BLOCKS}M "${NSWAP}"
$CHMOD $PERM "${NSWAP}"
if [ -s "${NSWAP}" ]
then MDEV=$($MDCONFIG -a -t vnode -f "${NSWAP}")
printf "${MDEV} ${NSWAP}\n" >>"${SWAPLIST}"
echo "swapmon$VERSION[$$] Swapusage ${SWAPUSAGE}%($((${SWAPCTLSK##* }/1024))/$(($SWAPTOTAL/1024)) M), activated new swapdevice ${MDEV} backed by ${NSWAP}."|$LOGGER
$SWAPON /dev/${MDEV}
$SWAPCTL -lh|$SED -e "s/^/swapmon$VERSION[$$] /g"|$LOGGER
else echo "swapmon$VERSION[$$] Creating swapfile ${NSWAP} failed! :("|$LOGGER
fi
fi
while [ \( ${SWAPUSAGE} -lt ${SWAP_LOW} \) -a -s "${SWAPLIST}" ]
do MDEV=$(/usr/bin/tail -1 "${SWAPLIST}")
SWAPF=${MDEV#* }
MDEV=${MDEV%% *}
if [ -s "${SWAPF}" ]
then if [ "${SWAPF}" = "$($MDCONFIG -l -u ${MDEV}|/usr/bin/awk '{print $4}')" ]
then if [ -n "$($SWAPCTL -l|$SED -n '1!p'|/usr/bin/grep '/dev/'${MDEV})" ]
then echo "swapmon$VERSION[$$] Swapusage ${SWAPUSAGE}%($((${SWAPCTLSK##* }/1024))/$(($SWAPTOTAL/1024)) M), deactivating swapdevice ${MDEV}."|$LOGGER
$SWAPCTL -lh|$SED -e "s/^/swapmon$VERSION[$$] /g"|$LOGGER
$SWAPOFF "/dev/${MDEV}"
fi
echo "swapmon$VERSION[$$] Detaching vnode ${MDEV}."|$LOGGER
$MDCONFIG -d -u ${MDEV} >/dev/null
$RM -f "${SWAPF}"
else echo "swapmon$VERSION[$$] Swapfile ${SWAPF} is not attached to ${MDEV} as it should be!?"|$LOGGER
for MDEV in $($MDCONFIG -l)
do echo "swapmon$VERSION[$$] $($MDCONFIG -l -u ${MDEV})"|$LOGGER
done
fi
else echo "swapmon$VERSION[$$] ${SWAPF} is not a valid swapfile."|$LOGGER
fi
$SED -I '' -n '$!p' "${SWAPLIST}"
SWAPCTLSK=$($SWAPCTL -sk)
SWAPTOTAL=${SWAPCTLSK#* }
SWAPTOTAL=${SWAPTOTAL% *}
SWAPUSAGE=$(( ${SWAPCTLSK##* } * 100 / $SWAPTOTAL ))
done
}
add_def_swap # this will check if there is some swap configured
# we can't work without
case "$1" in
start)
$0 -F <&- 2>&1 >/dev/null &
;;
stop)
if [ -s "${PIDFILE}" ]
then
PID=$(/bin/cat ${PIDFILE})
if ( /bin/ps -p $PID|grep -q $0 )
then /bin/kill $PID
fi
$RM "${PIDFILE}"
fi
;;
-F)
echo $$ >"${PIDFILE}"
echo "swapmon$VERSION[$$] Writing pid $$ to pidfile ${PIDFILE}."|$LOGGER
cd / || exit 1
while [ -f "${PIDFILE}" ]
do check_swap
sleep ${DELAY}
done
;;
'')
if [ -r "${LOCKF}" ]
then
echo "${LOCKF} exists"
exit 1;
else
echo $$ >"${LOCKF}"
LOGGER="/bin/cat"
check_swap
fi
$RM -f "${LOCKF}"
;;
*)
echo "$* not supported"
;;
esac
|
