I'd like to think you will want to avoid the use of swap at almost all costs because it'll slow the system down by a lot. So really you don't need 1:1 for a server that isn't using suspend to disk. You only need enough swap so that things can chug (slowly) without totally imploding, giving you enough time to kill whatever is hogging RAM or do a more graceful reboot than you otherwise would. It's fairly stable now, but the longer term solution for this is LVM thin provisioning will mean a bulk of extents will remain free (not associated with any LV) until they're needed. While you wouldn't use a thin volume for swap, but free extents can be used to make the conventional LV used for swap bigger. And for thin volumes it can mostly obviate even having to resize them.