Hi, what version of cloud-init are you using? This functionality is only availble in trunk since 2014-10-01. It is only in Ubuntu vivid and utopic, not in trusty.
That said, I just launched an instance with this config: #cloud-config swap: size: auto filename: /swap.img maxsize: 8G /var/log/cloud-init.log says: Jan 15 15:33:18 vivid-20150115-153256 [CLOUDINIT] cc_mounts.py[DEBUG]: suggest 8182 MB swap for 7984 MB memory with '9092 MB' disk given max=8192 MB [max=8182 MB]' Jan 15 15:33:32 vivid-20150115-153256 [CLOUDINIT] util.py[DEBUG]: creating swap file '/swap.img' of 8182MB took 14.301 seconds $ ls -lh /swap.img ; du /swap.img -rw------- 1 root root 8.0G Jan 15 15:33 /swap.img 8378372 /swap.img $ free total used free shared buffers cached Mem: 8176028 8009932 166096 308 9280 7680480 -/+ buffers/cache: 320172 7855856 Swap: 8378364 0 8378364 Launching another instance without the specified 'max' gives me: Jan 15 15:44:41 vivid-20150115-154415 [CLOUDINIT] cc_mounts.py[DEBUG]: suggest 2273 MB swap for 7984 MB memory with '9092 MB' disk given max=None [max=2273 MB]' The algorithm for 'auto' is agreeably nebulus, but I feel that any algoritm is going to seem odd/broken for some set. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1410824 Title: Swap space with mounts module not working To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/cloud-init/+bug/1410824/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs