P4L2 - Distributed File Systems Flashcards
T/F: Modern operating systems export a high-level filesystem interface to abstract all of the different types of storage devices present on a machine
True
What is a Distributed Filesystem
Environments that involve multiple machines for the delivery of the filesystem service
What is the replicated system DFS model
All files are replicated and available on every sever machine
What are the benefits of the replicated system DFS model
- Fault Tolerant
2. Highly Available
What is the partitioned DFS model
Each server holds only some subset of the total files
What are the benefits of the partitioned DFS model?
- Scalable
T/F: It’s uncommon to see a DFS that utilizes both partitioning and replication
False
What is the 3rd alternative to partitioned/replicated DFS models?
Files stored and served from all machines. All systems are peers
A _____ server keeps no notion of which files/blocks are being accessed, which operations are being performed, how many clients are accessing how many files
stateless
In a stateless server, every request must be _______
self-contained
T/F: Stateless servers can be used with models that rely on caching?
False! Without state, we CANNOT achieve consistency management
What are some benefits of stateless server?
- Since there is no state on the server, there is no CPU/memory utilization required to manage that state
- Design is very resilient
A _____ server maintains information about the clients in the system, which files are being accessed, which types of accesses are being performed, which clients have a file cached, which clients have read/written the file
stateful
T/F: Stateful servers can be used with caching models
True
Describe session semantics
Client writes back whatever data was modified on CLOSE. Whenever a client needs to open a file, the cache is skipped
