you do _not_ want to be using swap space on raw nand or even eMMC. or USB-based external storage media. in fact, you don't want to be using swap space at all... with the exception possibly of compswap (the much better version of zram, which linus torvalds refused to allow the full set of patches for, into the linux kernel).
NBD-based (network block device) swap is also a viable solution with Gb eth, and is better than getting OOM-killed...