UNIX for Dummies Questions & Answers

I'm getting fork failed errors. I was told I needed to upgrade my swap space but also need to change some values for some parameters in the kernel and add 2 new parameters. I not sure of the correct way of doing this.
Thanks in Advance

What flavour of UNIX are you running?

Sun Solaris 7

in Linux it is pretty easy:

this example will give you extra 32MB of swap space than you already have(use free command to see existing swap spce)

# dd if=/dev/zero of=/example/moreswap bs=1024 count=32768.
this makes an empty 32 MB file you can use for swap space.

# mkswap /example/moreswap
you have now turned "moreswap" empty file into 32MB of additional swap space.

Now to use it:
#swapon /example/moreswap

check to see how much is available by running the 'free' command. you will see you have 32MB more than you had before.

If you want this to be persistent across boots, edit the /etc/rc.d/rc.local file. add these lines to the bottom of the file:

swapon /example/moreswap

To disable:
# swapoff /example/moreswap
To remove:
# rm /moreswap

in solaris instead of this you can use(you should confirm it by some other way)

# mkfile 32m /example/moreswap
# swap -a /example/moreswap

if you want this to be persistent across boots, add following lines to your filesystem table

/example/moreswap      -      -      swap      -      no      -

hope this will help you

Not sure why you need to change the kernel to setup more swap space. This is normally done independent of the kernel. mib gives an example of adding more (filesystem)swap in this thread; notice that a kernel rebuild is not required. Same is true for most OS. You create swap space and turn it on using system level utilities.

Note, there are other ways to add swap, including disk partition raw swap space. You create this with a disk formating utilility (such as fdisk) and 'turn-it-on' in a similar manner.

[Edited by Neo on 04-15-2001 at 04:25 PM]