Swap size for laptop with 3GB RAM

English Hardware
#1

I am installing openSUSE 11.1 (again) on a 64-bit laptop with 3GB of physical RAM. The installer wants to recommend a 2GB swap partition, but I think it should be at least 3GB so that suspend-to-disk will work. I have read various sources that claim a swap partition can be no larger than 2GB (for x86) but nobody seems to know what the limit is for x86_64. Also, the first time I tried to do this I used a >2GB swap partition, and somehow I would up with a badly broken installation - but I don’t know for sure if that was the cause.

What’s the conventional wisdom on swap partition size for laptops with a lot of RAM?

#2 

free -m

             total       used       free     shared    buffers     cached
Mem:          3952       3664        288          0        185       2987
-/+ buffers/cache:        491       3461
Swap:         4705          0       4705

So much for the “Swap cannot be bigger than 2GB”-theory.

I always use swap = RAM + some extra space for safety (and I use the same swap for i586 and x86_64 which are both installed on my laptop).

#3

I have two 8GB swap partitions. So much for the 2GB theory too.

#4

I use swap = ram, no suspend to disk

#5

When you have plenty of ram, like more than 2Gb, the old rule ram = swap + x does not make sense anymore.

I have 4Gb of RAM and use a swap of only 2Gb, though it has never been used for more than 500 Mb.

Note that suspend to disk compress the data, so you don’t need to have the exact same amount of swap.

And in case you got a problem - so far never got this issue, just close the greediest apps before suspending - that’s all and you will save a lot of disk space.

#6

Well, I went ahead and gave it a 4GB swap partition (on the grounds that this laptop supports up to 4GB RAM), and haven’t had any trouble this time around. I think I had other problems with my partition setup last time. Thanks for all the replies.