What is the difference between swap and /tmp ?

Should i always create a separate partition for /tmp and how big this must be?

swap is used by the OS kernel. when it runs out of memory
it uses it as temporary storage. You can't touch it.
/tmp is just a general users/programs temp area
anyone can use it.

you don't need a /tmp partition.
a seperate /home partition is a good idea at least though.


billy

The swap partition is like virtual memory and /tmp is a place where Linux stores temporary files (like Windows Paging file and Temp directory). /tmp does not have to be on a separate partition and the Swap partition should be 2x the physical ram up to 500MB.

Baldrick

Swap does not have to be 2x the physical memory, though that should be safe with most situations. Personally, I have 320 MB of ram, and 176 MB of swap, and given that this is my home machine where I do not use many memory intensive applications (besides mozilla), the following (with fedora 1) is about as full as I have ever seen swap:

$ free
total used free shared buffers cached
Mem: 322132 305280 16852 0 36908 123200
-/+ buffers/cache: 145172 176960
Swap: 177876 85660 92216
$ swapon -s
Filename Type Size Used Priority
/dev/sdf8 partition 49436 28576 2
/dev/sdc1 partition 64220 28480 2
/dev/sda5 partition 64220 28604 2
$

Since I am now getting up to about 50% swap usage, I am thinking of adding a bit more swap, maybe to about the equivalent of memory. If I added more memory, I would need less swap. I had a work machine once however, where I needed 3X swap (back when memory was expensive). The point is, just keep an eye occasionally on the usage to fit your own needs.

thank you for your help guys!!