Swap shoots to 100% after a couple of hours of usage
For some reason or another, my swap usage will peak to 100% capacity after a couple hours of usage. My interface will then freeze, after which I have to wait 20 minutes time to be able to even move the mouse.
The current suspected culprit is Chromium or XChat as these are always present when this issue occurs. I'm leaning more towards XChat as I've previously noticed the freeze starting right around the time when I click on something related to XChat.
Among the other things I've noticed is the Swap usage will build up over time.
I've also had Emesene and Dropbox open, but i doubt they're the root cause of the issue as they're just idling when the interface freezes.
Rebooting is currently my only fix at the moment, (That I can find anyway...)but if the interface didn't completely stop working, in that case it would be a hard reset. Also when the swap is full, the HDD light is constantly on.
Edit:
Found some additional information. Here's the output of free -m:
total used free shared buffers cached
Mem: 3760 3653 107 0 4 2638
-/+ buffers/cache: 1010 2750
Swap: 3890 2643 1247
As you can see, the physical memory is cached for some reason, while the free ones are relatively small. I think this is causing the swap usage.
I need this fixed as I currently need to shutdown every 2 days.
Thanks
Update: As per request /etc/fstab
UUID=20fab2bb-2424-40b0-ae2b-74693ea83f45 / ext4 errors=remount-ro,user_xattr 0 1
# swap was on /dev/sda5 during installation
UUID=e04c1c74-9b99-4f07-8d3c-f0d6e8d3c465 none swap sw 0 0
Update:
ps -aux info
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 1 0.0 0.0 24144 1968 ? Ss Jul11 0:02 /sbin/init
root 2 0.0 0.0 0 0 ? S Jul11 0:00 [kthreadd]
root 3 0.0 0.0 0 0 ? S Jul11 0:00 [ksoftirqd/0]
root 6 0.0 0.0 0 0 ? S Jul11 0:00 [migration/0]
root 17 0.0 0.0 0 0 ? S< Jul11 0:00 [cpuset]
root 18 0.0 0.0 0 0 ? S< Jul11 0:00 [khelper]
root 19 0.0 0.0 0 0 ? S< Jul11 0:00 [netns]
root 21 0.0 0.0 0 0 ? S Jul11 0:00 [sync_supers]
root 22 0.0 0.0 0 0 ? S Jul11 0:00 [bdi-default]
root 23 0.0 0.0 0 0 ? S< Jul11 0:00 [kintegrityd]
root 24 0.0 0.0 0 0 ? S< Jul11 0:00 [kblockd]
root 25 0.0 0.0 0 0 ? S< Jul11 0:00 [ata_sff]
root 26 0.0 0.0 0 0 ? S Jul11 0:00 [khubd]
root 27 0.0 0.0 0 0 ? S< Jul11 0:00 [md]
root 30 0.0 0.0 0 0 ? S Jul11 0:00 [khungtaskd]
root 31 0.0 0.0 0 0 ? S Jul11 0:05 [kswapd0]
root 32 0.0 0.0 0 0 ? SN Jul11 0:00 [ksmd]
root 33 0.0 0.0 0 0 ? SN Jul11 0:00 [khugepaged]
root 34 0.0 0.0 0 0 ? S Jul11 0:00 [fsnotify_mark]
root 35 0.0 0.0 0 0 ? S Jul11 0:00 [ecryptfs-kthr]
root 36 0.0 0.0 0 0 ? S< Jul11 0:00 [crypto]
root 40 0.0 0.0 0 0 ? S< Jul11 0:00 [kthrotld]
root 43 0.0 0.0 0 0 ? S< Jul11 0:00 [kmpathd]
root 44 0.0 0.0 0 0 ? S< Jul11 0:00 [kmpath_handle]
root 273 0.0 0.0 0 0 ? S Jul11 0:00 [scsi_eh_0]
root 274 0.0 0.0 0 0 ? S Jul11 0:00 [scsi_eh_1]
root 275 0.0 0.0 0 0 ? S Jul11 0:00 [scsi_eh_2]
root 276 0.0 0.0 0 0 ? S Jul11 0:00 [scsi_eh_3]
root 277 0.0 0.0 0 0 ? S Jul11 0:01 [scsi_eh_4]
root 279 0.0 0.0 0 0 ? S Jul11 0:00 [scsi_eh_5]
root 353 0.0 0.0 0 0 ? S Jul11 0:01 [jbd2/sda1-8]
root 354 0.0 0.0 0 0 ? S< Jul11 0:00 [ext4-dio-unwr]
root 404 0.0 0.0 17052 520 ? S Jul11 0:00 upstart-udev-br
root 414 0.0 0.0 21536 652 ? S<s Jul11 0:00 udevd --daemon
root 627 0.0 0.0 0 0 ? S Jul11 0:00 [ips-adjust]
root 630 0.0 0.0 0 0 ? S Jul11 0:02 [ips-monitor]
root 631 0.0 0.0 0 0 ? S< Jul11 0:00 [kmemstick]
root 655 0.0 0.0 0 0 ? S< Jul11 0:00 [kpsmoused]
root 657 0.0 0.0 0 0 ? S< Jul11 0:00 [cfg80211]
root 806 0.0 0.0 15004 496 ? S Jul11 0:00 upstart-socket-
root 819 0.0 0.0 0 0 ? S< Jul11 0:00 [iwlagn]
root 858 0.0 0.0 0 0 ? S< Jul11 0:00 [l2cap]
root 911 0.0 0.0 0 0 ? S< Jul11 0:00 [hd-audio0]
root 920 0.0 0.0 0 0 ? S< Jul11 0:00 [hd-audio1]
syslog 989 0.0 0.0 119988 924 ? Sl Jul11 0:00 rsyslogd -c4
102 1002 0.0 0.0 25496 2316 ? Ss Jul11 0:18 dbus-daemon --s
root 1014 0.0 0.0 83168 2848 ? Ssl Jul11 0:00 gdm-binary
avahi 1018 0.0 0.0 32132 1336 ? S Jul11 0:00 avahi-daemon: r
avahi 1019 0.0 0.0 32008 156 ? S Jul11 0:00 avahi-daemon: c
root 1020 0.0 0.0 158344 3452 ? Ssl Jul11 0:06 NetworkManager
root 1022 0.0 0.0 125528 2376 ? Sl Jul11 0:01 /usr/sbin/conso
root 1037 0.0 0.0 64656 1972 ? S Jul11 0:00 /usr/sbin/modem
root 1113 0.0 0.0 136612 3404 ? Sl Jul11 0:02 /usr/lib/policy
root 1130 0.0 0.0 77284 2012 ? Ss Jul11 0:00 /usr/sbin/cupsd
root 1170 0.0 0.0 97816 2704 ? Sl Jul11 0:00 /usr/lib/gdm/gd
root 1180 0.0 0.0 6196 528 tty4 Ss+ Jul11 0:00 /sbin/getty -8
root 1183 0.0 0.0 6196 528 tty5 Ss+ Jul11 0:00 /sbin/getty -8
root 1196 0.0 0.0 6196 532 tty2 Ss+ Jul11 0:00 /sbin/getty -8
root 1199 0.0 0.0 6196 528 tty3 Ss+ Jul11 0:00 /sbin/getty -8
root 1204 0.0 0.0 6196 528 tty6 Ss+ Jul11 0:00 /sbin/getty -8
root 1214 0.0 0.0 4416 784 ? Ss Jul11 0:00 acpid -c /etc/a
root 1217 0.0 0.0 18928 844 ? Ss Jul11 0:00 cron
daemon 1220 0.0 0.0 16728 200 ? Ss Jul11 0:00 atd
root 1230 1.8 1.1 533108 44700 tty7 Ss+ Jul11 32:07 /usr/bin/X :0 -
mysql 1245 0.0 0.0 168744 2572 ? Ssl Jul11 0:10 /usr/sbin/mysql
root 1248 0.0 0.0 15780 564 ? Ss Jul11 0:05 /usr/sbin/irqba
root 1262 0.0 0.0 28932 1260 ? S Jul11 0:01 /sbin/wpa_suppl
root 1292 0.0 0.0 4400 368 ? S Jul11 0:00 /usr/sbin/hddte
root 1411 0.0 0.0 37364 1092 ? Ss Jul11 0:00 /usr/lib/postfi
root 1465 0.0 0.0 65800 672 ? Ss Jul11 0:00 /usr/sbin/winbi
root 1535 0.0 0.0 0 0 ? S< Jul11 0:00 [krfcommd]
root 1569 0.0 0.0 173652 1308 ? Ss Jul11 0:00 /usr/sbin/apach
www-data 1582 0.0 0.0 173652 236 ? S Jul11 0:00 /usr/sbin/apach
www-data 1583 0.0 0.0 173652 236 ? S Jul11 0:00 /usr/sbin/apach
www-data 1584 0.0 0.0 173652 236 ? S Jul11 0:00 /usr/sbin/apach
www-data 1585 0.0 0.0 173652 236 ? S Jul11 0:00 /usr/sbin/apach
www-data 1586 0.0 0.0 173652 236 ? S Jul11 0:00 /usr/sbin/apach
root 1630 0.0 0.0 0 0 ? S Jul11 0:00 [flush-8:0]
root 1637 0.0 0.0 65800 224 ? S Jul11 0:00 /usr/sbin/winbi
root 1766 0.0 0.0 6196 528 tty1 Ss+ Jul11 0:00 /sbin/getty -8
root 1820 0.0 0.0 135156 2396 ? Sl Jul11 0:00 /usr/lib/gdm/gd
rtkit 1825 0.0 0.0 103164 1040 ? SNl Jul11 0:00 /usr/lib/rtkit/
root 1830 0.0 0.1 144204 4276 ? Sl Jul11 0:15 /usr/lib/upower
ulti 2065 0.0 0.1 189116 3896 ? Sl Jul11 0:00 /usr/bin/gnome-
ulti 2084 0.0 0.1 243352 6428 ? Ssl Jul11 0:03 gnome-session -
ulti 2116 0.0 0.0 60840 3028 ? Sl Jul11 0:31 /usr/bin/ibus-d
ulti 2120 0.0 0.0 12092 16 ? Ss Jul11 0:00 /usr/bin/ssh-ag
ulti 2123 0.0 0.0 26400 328 ? S Jul11 0:00 /usr/bin/dbus-l
ulti 2124 0.0 0.0 27712 3128 ? Ss Jul11 1:15 //bin/dbus-daem
ulti 2126 0.0 0.0 130548 2792 ? Sl Jul11 0:00 /usr/lib/ibus/i
ulti 2128 0.0 0.5 456024 19524 ? Sl Jul11 0:41 /usr/bin/python
ulti 2130 0.0 0.1 145864 5700 ? S Jul11 0:00 /usr/lib/ibus/i
ulti 2135 0.0 0.1 61484 3972 ? S Jul11 0:04 /usr/lib/libgco
ulti 2137 0.0 0.1 72168 5692 ? S Jul11 0:03 /usr/lib/ibus-p
ulti 2145 0.0 0.2 474668 8128 ? Ssl Jul11 0:18 /usr/lib/gnome-
ulti 2149 0.0 0.3 344292 14180 ? Sl Jul11 0:22 /usr/lib/notify
ulti 2158 0.0 0.0 55960 2148 ? S Jul11 0:00 /usr/lib/gvfs/g
ulti 2163 0.0 0.0 81008 1488 ? Ssl Jul11 0:00 /usr/lib/gvfs//
ulti 2167 0.3 0.2 279904 8684 ? Sl Jul11 6:35 /usr/bin/compiz
ulti 2186 0.0 0.0 22608 768 ? S Jul11 0:13 syndaemon -i 0.
ulti 2188 0.0 0.0 161972 3272 ? S Jul11 0:00 /usr/lib/gvfs/g
root 2191 0.0 0.0 136120 3504 ? Sl Jul11 0:00 /usr/lib/udisks
root 2192 0.0 0.0 45168 804 ? S Jul11 0:02 udisks-daemon:
ulti 2195 0.0 0.0 77352 1752 ? Sl Jul11 0:01 /usr/lib/gvfs/g
ulti 2198 0.0 0.0 63556 2028 ? S Jul11 0:00 /usr/lib/gvfs/g
ulti 2199 0.1 1.4 738152 55152 ? Sl Jul11 2:27 nautilus
ulti 2201 0.0 0.4 398040 16004 ? SLl Jul11 0:25 nm-applet --sm-
ulti 2202 0.0 0.1 347020 6020 ? Sl Jul11 0:00 /usr/lib/evolut
ulti 2203 0.0 0.2 317560 8580 ? Sl Jul11 0:00 bluetooth-apple
ulti 2204 0.0 0.1 289280 5972 ? Sl Jul11 0:01 zeitgeist-datah
ulti 2207 0.0 0.4 381248 18424 ? Sl Jul11 0:16 gnome-panel
ulti 2211 0.0 0.2 339028 10792 ? Sl Jul11 0:00 /usr/lib/policy
ulti 2212 0.0 0.6 478920 24388 ? Sl Jul11 0:02 synapse --start
ulti 2219 0.0 0.3 188988 11680 ? Sl Jul11 0:02 /usr/bin/python
ulti 2221 0.1 0.3 995912 13024 ? Sl Jul11 2:20 python /usr/bin
ulti 2223 0.0 0.3 480188 13952 ? Sl Jul11 0:40 gnome-power-man
ulti 2232 0.0 0.5 688680 20392 ? Ssl Jul11 0:20 /home/ulti/.d
ulti 2235 0.0 0.0 10848 452 ? S Jul11 0:00 /bin/cat
ulti 2240 0.0 0.1 330376 5452 ? Sl Jul11 0:01 /usr/lib/evolut
ulti 2243 0.0 0.0 0 0 ? Z Jul11 0:00 [zei] <defunct>
ulti 2261 0.0 0.1 180360 5624 ? S Jul11 0:00 /usr/lib/gnome-
ulti 2325 0.0 0.2 281168 8304 ? Sl Jul11 0:00 /usr/lib/gnome-
ulti 2327 0.0 0.0 60780 2912 ? S Jul11 0:00 /usr/lib/gvfs/g
ulti 2330 0.0 0.0 56812 2496 ? S Jul11 0:00 /usr/bin/obex-d
ulti 2331 0.0 0.1 245636 5244 ? Ss Jul11 0:04 gnome-screensav
ulti 2348 0.0 0.0 4220 488 ? Ss Jul11 0:00 /bin/sh -c /usr
ulti 2349 0.0 0.3 339428 13760 ? Sl Jul11 0:18 /usr/bin/unity-
ulti 2351 0.0 0.0 161388 2380 ? Ssl Jul11 0:00 /usr/lib/bonobo
ulti 2368 0.0 0.3 346704 15276 ? Sl Jul11 1:09 /usr/lib/gnome-
ulti 2371 0.0 0.2 372276 10936 ? Sl Jul11 0:21 /usr/lib/gnome-
ulti 2373 0.0 0.2 298172 9268 ? Sl Jul11 0:00 /usr/lib/gnome-
ulti 2375 0.4 0.5 415272 21692 ? Sl Jul11 7:48 /usr/lib/indica
ulti 2377 0.0 0.2 276272 8636 ? Sl Jul11 0:24 /usr/lib/gnome-
ulti 2411 0.0 0.0 49920 2144 ? S Jul11 0:00 /usr/lib/gvfs/g
ulti 2414 0.0 0.0 122464 2396 ? Sl Jul11 0:00 /usr/lib/d-conf
ulti 2421 0.0 0.1 305576 4624 ? Sl Jul11 0:00 /usr/lib/indica
ulti 2423 0.0 0.1 227072 4028 ? Sl Jul11 0:00 /usr/lib/indica
ulti 2425 0.0 0.1 405464 4152 ? Sl Jul11 0:01 /usr/lib/indica
ulti 2427 0.0 0.1 315800 6724 ? Sl Jul11 0:01 /usr/lib/indica
ulti 2429 0.0 0.1 209964 6180 ? Sl Jul11 0:35 /usr/lib/indica
ulti 2431 0.0 0.1 311128 4096 ? Sl Jul11 0:00 /usr/lib/indica
ulti 2460 0.0 0.0 159216 3016 ? Sl Jul11 0:01 /usr/lib/geoclu
ulti 2466 0.0 0.0 56220 2008 ? S Jul11 0:00 /usr/lib/gvfs/g
ulti 2491 0.0 0.2 237108 7964 ? S Jul11 0:11 /usr/bin/python
ulti 2511 0.1 0.5 431804 22796 ? Sl Jul11 2:35 xchat
ulti 2513 0.0 0.2 225192 10000 ? S Jul11 0:07 /usr/lib/bamf/b
ulti 2517 0.0 0.3 368132 12532 ? Sl Jul11 0:44 /usr/bin/python
ulti 2555 0.3 0.2 291168 7864 ? Sl Jul11 5:24 skype
ulti 2556 0.0 0.2 322488 9860 ? Sl Jul11 0:01 update-notifier
ulti 2628 0.0 0.3 334148 15260 ? Dl Jul11 0:07 gnome-terminal
ulti 2636 0.0 0.0 14612 764 ? S Jul11 0:00 gnome-pty-helpe
ulti 6237 0.5 2.1 742192 81440 ? SLl Jul11 5:56 /opt/google/chr
ulti 6242 0.0 0.0 238432 3284 ? S Jul11 0:11 /opt/google/chr
ulti 6244 0.0 0.1 274712 5940 ? S Jul11 0:00 /opt/google/chr
ulti 6267 0.1 1.6 958724 65380 ? SNl Jul11 1:49 /opt/google/chr
ulti 6275 0.0 0.3 869444 13328 ? Sl Jul11 0:06 /opt/google/chr
ulti 6303 0.0 0.3 869440 13668 ? Sl Jul11 0:07 /opt/google/chr
ulti 6342 0.0 0.4 870532 15612 ? Sl Jul11 0:08 /opt/google/chr
ulti 6347 0.0 0.3 869444 13268 ? Sl Jul11 0:06 /opt/google/chr
ulti 6358 1.1 1.4 1003268 54604 ? Sl Jul11 12:00 python /usr/bin
ulti 7642 0.0 0.1 271220 7344 ? S Jul11 0:00 /usr/lib/gvfs/g
ulti 9719 0.0 0.1 28516 5580 pts/1 Ss Jul11 0:00 bash
root 10577 0.0 0.0 0 0 ? S 08:15 0:00 [migration/1]
root 10579 0.0 0.0 0 0 ? S 08:15 0:00 [ksoftirqd/1]
root 10580 0.0 0.0 0 0 ? S 08:15 0:00 [migration/2]
root 10582 0.0 0.0 0 0 ? S 08:15 0:00 [ksoftirqd/2]
root 10583 0.0 0.0 0 0 ? S 08:15 0:00 [migration/3]
root 10585 0.0 0.0 0 0 ? S 08:15 0:00 [ksoftirqd/3]
root 10613 0.0 0.0 0 0 ? S< 08:15 0:00 [hci0]
root 10638 0.0 0.0 0 0 ? S 08:15 0:00 [mmcqd/0]
root 10894 0.0 0.0 7084 820 ? S 08:15 0:00 /sbin/dhclient
postfix 10995 0.0 0.0 39480 928 ? S 08:15 0:00 qmgr -l -t fifo
root 11013 0.0 0.0 15664 1152 ? Ss 08:16 0:00 /sbin/mount.ntf
ulti 11339 0.0 0.3 262796 13452 ? Sl 08:31 0:01 /opt/google/chr
ulti 12488 3.2 2.9 1044824 114420 ? Sl 09:33 10:16 python /usr/bin
ulti 12923 0.0 0.0 287192 2552 ? S<sl 09:53 0:04 /usr/bin/pulsea
ulti 12929 0.0 0.0 181372 3096 ? Sl 09:53 0:00 /usr/lib/pulsea
root 15585 0.0 0.0 84056 3488 ? S 11:16 0:00 /usr/bin/python
ulti 15756 0.0 0.0 71016 3080 ? S 11:23 0:00 /usr/lib/gvfs/g
root 15952 0.0 0.0 73200 2764 ? S 11:25 0:00 /usr/bin/python
ulti 15998 0.0 0.0 0 0 ? Z 11:25 0:00 [sh] <defunct>
root 16013 0.0 0.0 0 0 ? S 11:26 0:01 [kworker/1:1]
root 16672 0.0 0.0 0 0 ? S 11:33 0:01 [kworker/u:0]
root 16697 0.0 0.0 0 0 ? S 11:33 0:02 [kworker/2:1]
ulti 16937 0.0 0.0 42516 3556 pts/1 S+ 11:36 0:02 ssh -2 -C -D 80
root 17235 0.0 0.0 21532 684 ? S< 11:46 0:00 udevd --daemon
root 17236 0.0 0.0 21532 640 ? S< 11:46 0:00 udevd --daemon
root 17428 0.0 0.0 0 0 ? S 11:57 0:01 [kworker/u:2]
postfix 18676 0.0 0.0 39428 1372 ? S 13:15 0:00 pickup -l -t fi
ulti 19703 0.0 0.1 28516 5844 pts/0 Ss 14:04 0:00 bash
root 19838 0.0 0.0 23252 1644 ? Ss 14:05 0:00 /usr/sbin/bluet
root 20081 0.0 0.0 0 0 ? S 14:09 0:00 [kworker/3:0]
root 20269 0.0 0.0 0 0 ? S 14:14 0:00 [kworker/2:2]
root 20322 0.0 0.0 0 0 ? S 14:15 0:00 [kworker/1:2]
root 20639 0.0 0.0 0 0 ? S 14:26 0:00 [kworker/3:1]
root 20711 0.0 0.0 0 0 ? S 14:30 0:00 [kworker/0:1]
root 20805 0.0 0.0 0 0 ? S 14:33 0:00 [kworker/u:3]
root 20861 0.0 0.0 0 0 ? S 14:35 0:00 [kworker/0:0]
root 21027 0.0 0.0 0 0 ? S 14:41 0:00 [kworker/0:2]
ulti 21098 2.7 1.0 893504 39720 ? SNl 14:44 0:01 /opt/google/chr
ulti 21116 2.1 0.6 381512 24504 ? Sl 14:45 0:01 geany
ulti 21120 0.0 0.0 14612 828 ? S 14:45 0:00 gnome-pty-helpe
ulti 21121 0.5 0.1 28504 5812 pts/2 Ss+ 14:45 0:00 /bin/bash
ulti 21236 7.1 1.0 895512 41708 ? Sl 14:45 0:01 /opt/google/chr
ulti 21246 0.0 0.0 21932 1400 pts/0 R+ 14:46 0:00 ps -aux
vmstats after swapiness is set 10
procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu----
r b swpd free buff cache si so bi bo in cs us sy id wa
2 0 1458588 119320 2292 2748584 1 13 32 25 16 192 6 2 90 2
Why is the virtual memory usage so high? That's way higher than what both my swap and my memory can offer.
smap info: These are long
- Chrome Memory from smaps - ~ 930MB VIRT
- Emesene memory from smaps - ~ 900MB VIRT
Update: Here's recently an out of memory event (I turned swap off at this point, also the cached memory is taking up round 2.5GB at the point, and only ~1GB of physical memory is used, so technically I have another 2.5GB to work with due to the supposed taking back of the cache by the kernel):
Syslog event showing the supposed "out of memory event"
Also a page showing my exact problem: http://raj2796.wordpress.com/2009/11/09/reducing-cached-memory-usage-linux-high-memory-usage-diagnosing-and-troubleshooting-on-vmware-and-out-of-memory-oom-killer-problem-and-solution/
How do I configure swappiness?
The Linux kernel provides a tweakable set ting that controls how often the swap file is used, called swappiness
A swappiness setting of zero means that the disk will be avoided unless absolutely necessary (you run out of memory), while a swappiness setting of 100 means that programs will be swapped to disk almost instantly.
Ubuntu system comes with a default of 60, meaning that the swap file will be used fairly often if the memory usage is around half of my RAM. You can check your own system's swappiness value by running:
one@onezero:~$ cat /proc/sys/vm/swappiness
60
As I have 4 GB of RAM, so I'd like to turn that down to 10 or 15. The swap file will then only be used when my RAM usage is around 80 or 90 percent. To change the system swappiness value, open /etc/sysctl.conf as root. Then, change or add this line to the file:
vm.swappiness = 10
Reboot for the change to take effect
You can also change the value while your system is still running
sysctl vm.swappiness=10
you can also clear your swap by running swapoff -a and then swapon -a as root instead of rebooting to achieve the same effect.
To calculate your swap Formula
free -m (total) / 100 = A
A * 10
root@onezero:/home/one# free -m
total used free shared buffers cached
Mem: 3950 2262 1687 0 407 952
-/+ buffers/cache: 903 3047
Swap: 1953 0 1953
so total is 3950 / 100 = 39.5 * 10 = 395
so what it mean is that when 10 % 395 MB of ram left then it start using swapiness
Help . Ubuntu . Swap
What is swappiness
The swappiness parameter controls the tendency of the kernel to move processes out of physical memory and onto the swap disk. Because disks are much slower than RAM, this can lead to slower response times for system and applications if processes are too aggressively moved out of memory.
. swappiness can have a value of between 0 and 100
. swappiness=0 tells the kernel to avoid swapping processes out of physical memory for as long as possible
. swappiness=100 tells the kernel to aggressively swap processes out of physical memory and move them to swap cache
The default setting in Ubuntu is swappiness=60. Reducing the default value of swappiness will probably improve overall performance for a typical Ubuntu desktop installation. A value of swappiness=10 is recommended, but feel free to experiment.
Started Using swap at 91%
As i have configured my system & vm to make use of ram at 90 % . At 90 % there was no swapping
after that i opened some application like Firefox & Shutter , its start swapping because of ram usage is above 90 %
I found this link Help.ubuntu.com Community: Swap FAQ. The part about swapiness stands out as a point to check. To check the value from a terminal type this in.
cat /proc/sys/vm/swappiness
Default desktop version is 60 which mine is. A server is 10. The higher the value the more aggressive swap is used. The help FAQ explains how to adjust the value.
I have 4G of RAM and swap, like your system, and have never noticed my swap partition used.