SWAP SPACE

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1

All,
I am using SOLARIS 7. I have formated my hard drive to consist of only 150MB of swap space. This isn't enough considering I am running Oracle. How do I create additional swap space?
Please list sources or commands.

PS mkswap doesn't work on my machine. ( I have swap and swapadd)

Thanks a bunch

2

(excerpt from
http://www.hp-partners.com/ptc\_public/html/technical\_support/SunInterop/2x_swap2.htm\)

To add a raw swap partition to a Solaris 2.x system, identify an unused partition on a disk. Traditionally, slice 1 is used for swap space. Add the following entry to /etc/vfstab, taking care to use the correct device name:

/dev/dsk/c0t1d0s1 - - swap - no -

Enable the new partition with the swap command:
swap -a /dev/dsk/c0t1d0s1

Check your change:

swap -l

swapfile dev swaplo blocks free

/dev/dsk/c0t3d0s1 32,25 8 164040 164040
/dev/dsk/c0t1d0s1 32,9 8 164040 164040

3

I did a little research regarding this issue.

It turns out that it is very simple...

first, create a file with a size in megabytes of the swap space you wish. I did this in the root directory for simplicity.

mkfile 1024 /swapfile

second, manually add the file as swap space

swap -a /swapfile

this is it!!

Now it gets interesting. To have the swap space mounted everytime you machine boots, you need to edit /etc/vfstab.

You'll have to look at vfstab(4) for the syntax of the file, but as I have learned---It's there if you read it

Thanks for all your help

SmartJuniorUnix......UNTIL NEXT TIME

4

There are many kinds of swap space. PxT accurately decribes disk space swap. Mr JuniorUnix accurately describes file space swap. Most people consider file space swap to be much less efficient and slower than disk space swap. I would recommend some research into the subject and make sure that you will be happy with file space swap vs. disk swap. Just to let you know, we never use file swap and always use raw disk swap. There is a considerable difference in performance between the two, as I recall.

5

If I have no disk space. Is my only option to utilize file swap space?

6

You can add another disk, partition some swap space, and use the rest for file systems.