[rhn-users] RHEL AS21 or AS3: is it safe to use swapoff on a live box?

[Corné Beerse]

Doerbeck, Christoph wrote:

> Pretty simple question:
> 
> Is it safe to run swapoff on a running box and expect a swap file to
> flush and relocate to other swapfiles?
> 
> Over time, we've had a number of systems which had small swap files
> added to relieve an immediate problem.  Now we would like to simply
> create a larger default swapfile and offline the smaller ones.
> Ideally we would prefer not to shutdown/reboot the servers.  All boxes
> are either AS21 or AS3...
> 
> Thoughts?

If you have multiple swap-locations, you can savely disable some, as long as the 
amount of used swap is available. You can even go less, as long as there is 
space in core memory. See `top` for the used memory.

Be noted, if you go low, have swapspace at hand to enable it once the 
performance drops or (worse) processes cannot be started due to memory problems.




CBee