DON'T!!!!We've been noticing quite a few customers attempting to add additional memory to their VPS by creating a swapfile. Seriously, don't. Attempting to do so will result in an
unbootable VPS, with two remedies:
1) Restarting the host server (which we're very unlikely to do).
2) Wiping & rebulding your VPS (we'll do this only after confirming that you understand you will lose all data during this process).
OpenVZ does not virtualize swap down to the individual VPS level. Instead, swap is handled at the host level, and your processes are given a slice of ram in which to run. To better understand how OpenVZ handles memory, see
http://wiki.openvz.org/UBC_systemwide_configuration#Memory_and_swap_spaceIf you need more working memory, upgrade your VPS. Utilizing large amounts of swap space significantly hinders disk I/O, so we recommend two things:
1) If you need just a little bit of swap, count on your "burst" window for this. We provide a very generous "burst" RAM allocation, and this extra "free" RAM is effectively what you'd use as swap space.
2) If you need large amounts of swap, please consider the significant performance issues you would cause for other customers and either upgrade your VPS to more accurately reflect your usage needs, or reduce your memory requirements.
