Computer Science Speaking Skills Talk

Friday, May 10, 2019 - 12:00pm to 1:00pm


Traffic21 Classroom 6501 Gates Hillman Centers



Evolving Ext4 for Shingled Disks

Drive-Managed SMR (Shingled Magnetic Recording) disks offer a plug-compatible higher-capacity replacement for conventional disks. For non-sequential workloads, these disks show bimodal behavior: After a short period of high throughput they enter a continuous period of low throughput. We introduce ext4-lazy, a small change to the Linux ext4 file system that significantly improves the throughput in both modes. We present benchmarks on four different drive-managed SMR disks from two vendors, showing that ext4-lazy achieves 1.7-5.4x improvement over ext4 on a metadata-light file server benchmark. On metadata-heavy benchmarks it achieves 2-13x improvement over ext4 on drive-managed SMR disks as well as on conventional disks.

Joint work with Theodore Ts'o (Google), Garth Gibson (CMU), and Peter Desnoyers (Northeastern)

Presented in Partial Fulfillment of the CSD Speaking Skills Requirement

For More Information, Contact:


Speaking Skills