[rhelv6-beta-list] My first experiences with RHEL6 beta

[Jonathan S Billings]

On 06/10/2010 05:19 AM, John Summerfield wrote:
> First, I did a text install. I was very surprised how many pointless
> questions it asked, and how many sensible ones it didn't ask. Like, "Do
> you wan swap?"
> 
> I do not want swap. I especially do not want 2 Gbytes of swap on a test
> virtual machine.
> 
> When I do want swap, I usually want a swap file, not a swap partition.
> Swap files are more flexible, they can be created and dispensed with at
> will. Its a minor task to add a swap file, provided only that disk space
> is available. It's even easier to dispense with swap and assign the
> recovered space to other tasks.

I do not think that your use of swap is very common amongst people who
administer Linux systems.

I would only consider running a system without swap in very unique
situations, and even then I'd probably leave the swap partition in place
and disable the swap when it was needed.  I would not consider an OS on
a VM one of those corner cases.

An OS running on a virtual machine (where there's typically less memory
than an average system) really would benefit from a swap partition,
particularly since memory is generally more expensive than disks space.

Swap improves performance on a system, due to the way the Linux memory
manager works.  Swap partitions are faster than swap files, and less
likely to be lost, corrupted or removed by accident.

If you actually have problems with how swap is responding, you might
benefit from experimenting with the vm.swappiness sysctl, although I've
found the default value (60) to be good enough for most cases.

-- 
Jonathan Billings <jsbillin at umich.edu>
College of Engineering - CAEN - Unix and Linux Support