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jldupont
Asked: 2009-10-27 04:29:39 +0800 CST

ubuntu: 8GB machine... 7.6GB swap space

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I've got Ubuntu 9.04 with 8GB and system monitor reports 2.6GB of Memory + 7.6GB of Swap. What gives?

free -m

jldupont@jldupont-desktop:~$ free -m
             total       used       free     shared    buffers     cached
Mem:          2644       1621       1023          0         29        474
-/+ buffers/cache:       1116       1528 
Swap:         7742          0       7742

swapon -s 

jldupont@jldupont-desktop:~$ swapon -s
Filename                Type        Size    Used    Priority
/dev/sda5                           partition   7928036 0   -1

uname -a

jldupont@jldupont-desktop:~$ uname -a
Linux jldupont-desktop 2.6.28-16-server #55-Ubuntu SMP Tue Oct 20 20:50:00 UTC 2009 i686 GNU/Linux

Dump of my dmesg output is available here.

linux

3 Answers

  1. Best Answer

    That seems odd... What does top or free -m from the command line report. If you are running a 32-bit installation without the PAE (Physical Address Extension) kernel you would only see ~ 3.2 GB of physical memory. If that is the case install:

    sudo apt-get install linux-headers-server linux-image-server linux-server

    to get the PAE kernel to use the full amount of memory. You won't get more than 4 GB per process, but that probably doesn't matter. Alternatively, you could use the 64-bit version if it is a 64-bit machine.

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  2. Check what memory is reported in the CMOS configuration - maybe you have faulty hardware.

    Assuming you have a 32-bit CPU, the system monitor should report 4.0 GiB memory. Try removing the excess 4GB. On the other hand, if you have a 64 bit CPU, then install the 64-bit version of Ubuntu.

    During installation on a new hard drive the swap partition normally defaults to the same size as the memory, so the 8GB seems normal. Although, in practice, the more memory that there is available the less likely you are to require swap space.

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  3. running the 32 bit version of Ubuntu? It won't see past 4 gig of memory unless running the 64 bit version.

    Running "file /sbin/init" on the terminal should give a hint of what bitness you're running.

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