Ensure your SSDs are mounted on /mnt

# mount -l

Add a 8GB swapfile to /mnt

# cd /mnt
# /bin/dd if=/dev/zero of=swapfile bs=1M count=8192
# chown root:root swapfile
# chmod 0600 swapfile

Activate your new swapfile

$ mkswap /mnt/swapfile
$ swapon /mnt/swapfile

I symlink tmp to the mnt directory as well…

# mkdir /mnt/tmp
# chown -R root:root /mnt/tmp
# chmod 1777 /mnt/tmp
# ln -s /mnt/tmp /tmp

Ensure both these are happy at reboot by adding/modifying these lines in /etc/fstab

/dev/xvd[X] /mnt ext3 defaults,usrquota 0 0
/mnt/swapfile swap swap defaults 0 0

PS: If you haven’t got any ephemeral storage attached to your EC2 instance, you’ll need to create an AMI from that instance, modify the attached volumes and create a new box attaching the EBS drives to it. A little bit of downtime, but hopefully worth it for the snappy swap space.

Ref:
http://www.centos.org/docs/5/html/5.1/Deployment_Guide/s2-swap-creating-file.html
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/InstanceStorage.html#Using_AddingDefaultLocalInstanceStorageToAMI

Categories: General

Jonathan Adjei

Jon's expertise in web development is legendary and he overseas all technical aspects of our projects from development to hosting (all through the command line!)Jon is excited by the latest techniques and keeps the company on track by finding ways to adopt new practices into our workflow.