DistOS 2019F 2019-11-04

Readings

GFS & Chubby

• Sanjay Ghemawat et al., "The Google File System" (SOSP 2003)
• Burrows, The Chubby Lock Service for Loosely-Coupled Distributed Systems (OSDI 2006)

Discussion Questions

GFS

• What was the key task GFS was built for?
• What were the unusual design decisions made for GFS (i.e., how did they change semantics from UNIX-like filesystems)
• Why did those design decisions make sense given the task GFS was designed for?
• To what extent is GFS distributed? How is it centralized?
• How does GFS achieve fault tolerance and high performance?
• What are the different kinds of servers in GFS? What are their roles?

Chubby

• To what extent is Chubby like a UNIX filesystem? How does its semantics differ?
• Why does Chubby run on so few computers? Is it scalable?
• What is Paxos? What is it for? Why is it important to Chubby?
• What are the use cases for Chubby? How was it used with GFS?

Other

• Do you think Chubby and GFS are sufficient for Google today? Has anything changed in their use cases?
• Other thoughts or questions?