SREcon19 Asia/Pacific - Hybrid XFS—Using SSDs to Supercharge HDDs at Facebook

Skanda Shamasunder, Facebook

Hard drive capacities are going up but the IOPs they supply are staying flat. This has led the Exabyte-scale storage community to get inventive in how we use our disks to get the most out of them. This talk is the story of how we at Facebook coupled SSDs with HDDs to unlock their full potential by productionizing a little used feature in XFS that was designed with a whole other use case in mind. What started off as an experiment has now been rolled out across the Facebook fleet and has allowed us to scale our storage systems to meet the ever growing IO demand. It is a lesson in how combining existing hardware and software in novel ways by taking informed risks can have huge payoffs and help us scale our systems.