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Richard
Asked: 2012-02-27 22:52:54 +0800 CST

How do I set the default size of /dev/shm?

  • 772

I'd like to change the default size of /dev/shm in Lubuntu 11.10 (also known as /run/shm now, I guess).

It doesn't seem to appear in my fstab:

# / was on /dev/sdb5 during installation
UUID=66ac63f0-45fa-4766-9d20-7c56bcd0460d /               ext3    noatime,errors=remount-ro 0       1
# /home was on /dev/sdb7 during installation
UUID=227f1b29-5d04-4c28-9c9c-ea70b1726434 /home           ext3    noatime         0       2
# swap was on /dev/sdb6 during installation
#UUID=9e13b7cc-1f75-4b4e-9e79-c0f7368de353 none            swap    sw              0       0
/dev/mapper/cryptswap1 none swap sw 0 0

tmpfs /tmp tmpfs defaults,noexec,nosuid 0 0
tmpfs /var/tmp tmpfs defaults,noexec,nosuid 0 0
lubuntu tmpfs

2 Answers

  1. Best Answer

    Try putting a /dev/shm line in the fstab file to override the default settings:

    tmpfs /dev/shm tmpfs defaults,noexec,nosuid,size=100M 0 0

    If that doesn't work, you can try remounting it after it's been mounted at boot, for example by putting this line into the /etc/rc.local file

    mount -o remount,size=100M /run/shm
    • 7

  2. Temporary increase tmpfs filesystem

    1) Open /etc/fstab with vi or any text editor of your choice,

    2) Locate the line of /dev/shm and use the tmpfs size option to specify your expected size, - e.g. 512MB:

    tmpfs      /dev/shm      tmpfs   defaults,size=512m   0   0

    e.g. 2GB:

    tmpfs      /dev/shm      tmpfs   defaults,size=2g   0   0
mount -o remount /dev/shm
    • 0