Storage 2: Costs and benefits, stdio

Overview

In this lecture, we describe access costs, metrics, and benefits of caching, and continue our exploration of the default standard I/O cache.

Full lecture notes on storageTextbook readings

Cache abstraction

Storage access costs

Cost model

Question 1

Metrics: Latency and throughput

Relationships between latency and throughput

High-latency, high-throughput I/O

AWS Snowmobile

Latency, throughput, and access costs

Reducing access costs

Cache optimizations

Batching

Prefetching

Write coalescing

Parallel access

Question 2

Cache correctness

coherence.cc

Exploring performance of file access

Exploring performance of access patterns