reduce the size of swap

bonedome · #1 21st August 2010, 07:01 PM

Hello
my laptop has 2Gb of ram, 4Gb of swap, 40Gb hdd and an intel pentium 1.40GHz cpu, even when compiling stuff or maxing out everything the 4Gb of swap is never touched, with such a small hdd I'd like to reduce the swap to about 2Gb (just in case) to free up some space, does anyone know what commands/tools are available to accomplish this ?
All help is graciously received

William Haller · #2 21st August 2010, 07:20 PM

If your partitions were laid out with lvm, then consult that suite of commands for more information (lvmreduce and the like). I must mention, though, that if you ever decide to use hibernate or suspend, you may well need the swap space, even if not during normal daily operations.

The space recovered, however, may well not be able to be used as anything other than a 2 G partition depending on how the partitions were laid out. That is, it may not be in a spot where the freed space can be combined with another existing partition. My first hard drive was 40 MBytes and we were happy to have that, so 2 GB still seems like a lot to me, but today it can vaporize pretty fast.

stevea · #3 21st August 2010, 07:58 PM

He can still hibernate so long as swap is the same size as DRAM or larger.

I think this is a good idea. If you ever tarted thrashing for memory so muchthat you needed 4GB you system ywould be pretty unpleasant to use. That's OK for a cheapie server but not a desktop,

LVM is always a thorn in the side - but I suggest (assuming LVM, that you disable the swap (see the swapon, swapoff commands) and then use 'system-config-lvm' command (part of the system-config-lvm package)to resize, then perhas "mkswap -U ,... /dev/..." to re-create the swap withthe corrcet UUID (see your /etc/fstab for the UUID).

bonedome · #4 22nd August 2010, 01:31 PM

Thank you gentlemen, I didn't think of hibernation or suspend although I think I've disabled hibernation anyway, I'll look into lvmreduce etc, I remember trying to view my lvm partitions with gparted in puppy linux but lvm is not supported

Quote:

The space recovered, however, may well not be able to be used as anything other than a 2 G partition depending on how the partitions were laid out. That is, it may not be in a spot where the freed space can be combined with another existing partition.

I was afraid of that, I'll post back if I can basically move some swap to the file system