LKBEN11095: Howto find mem information in linux
Symptom
You want to find out how much memory is in use
Cause
none
Solution
There are several ways to find out how much memory your system is using. Apart from litte information tools like xosview or Superkaramba sysinfo, you have the following command line tools.
- top
- /proc/meminfo
- free
Top will not just deliver memory information. A normal top output looks like:
top - 20:45:36 up 20 min, 1 user, load average: 0.38, 0.40, 0.35
Tasks: 133 total, 1 running, 132 sleeping, 0 stopped, 0 zombie
Cpu(s): 16.2% us, 3.0% sy, 2.0% ni, 69.8% id, 8.9% wa, 0.1% hi, 0.0% si
Mem: 905344k total, 825044k used, 80300k free, 110936k buffers
Swap: 1124508k total, 0k used, 1124508k free, 516980k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
5146 root 15 0 153m 20m 3132 S 11.9 2.3 1:05.79 Xorg
1 root 16 0 1568 532 460 S 0.0 0.1 0:01.03 init
2 root 34 19 0 0 0 S 0.0 0.0 0:00.00 ksoftirqd/0
3 root RT 0 0 0 0 S 0.0 0.0 0:00.00 watchdog/0
4 root 10 -5 0 0 0 S 0.0 0.0 0:00.08 events/0
5 root 11 -5 0 0 0 S 0.0 0.0 0:00.00 khelper
6 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 kthread
8 root 10 -5 0 0 0 S 0.0 0.0 0:00.14 kblockd/0
9 root 20 -5 0 0 0 S 0.0 0.0 0:00.00 kacpid
118 root 20 0 0 0 0 S 0.0 0.0 0:00.00 pdflush
119 root 15 0 0 0 0 S 0.0 0.0 0:00.03 pdflush
121 root 18 -5 0 0 0 S 0.0 0.0 0:00.00 aio/0
120 root 15 0 0 0 0 S 0.0 0.0 0:00.01 kswapd0
708 root 10 -5 0 0 0 S 0.0 0.0 0:00.01 kseriod
1800 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 khubd
1815 root 15 0 0 0 0 S 0.0 0.0 0:00.00 khpsbpkt
1835 root 15 0 0 0 0 S 0.0 0.0 0:00.00 knodemgrd_0
1904 root 15 0 0 0 0 S 0.0 0.0 0:00.10 kjournald
...
At the 4th line you see the memory information.
You can also use the /proc/meminfo information and show it at the commandline:
cat /proc/meminfo
MemTotal: 905344 kB
MemFree: 80864 kB
Buffers: 111164 kB
Cached: 516912 kB
SwapCached: 0 kB
Active: 422456 kB
Inactive: 327316 kB
HighTotal: 0 kB
HighFree: 0 kB
LowTotal: 905344 kB
LowFree: 80864 kB
SwapTotal: 1124508 kB
SwapFree: 1124508 kB
Dirty: 184 kB
Writeback: 0 kB
Mapped: 183416 kB
Slab: 64332 kB
CommitLimit: 1577180 kB
Committed_AS: 357872 kB
PageTables: 2400 kB
VmallocTotal: 114680 kB
VmallocUsed: 5832 kB
VmallocChunk: 108540 kB
And last but not least you can use the command free.
free
total used free shared buffers cached
Mem: 905344 826172 79172 0 111316 517252
-/+ buffers/cache: 197604 707740
Swap: 1124508 0 1124508
Disclaimer:
The information provided in this document is intended for your information only. Lubby makes no claims to the validity of this information. Use of this information is at own risk!About the Author
Author:
- Keskon GmbH & Co. KGWim Peeters is electronics engineer with an additional master in IT and over 30 years of experience, including time spent in support, development, consulting, training and database administration. Wim has worked with SQL Server since version 6.5. He has developed in C/C++, Java and C# on Windows and Linux. He writes knowledge base articles to solve IT problems and publishes them on the Lubby Knowledge Platform.