Paper Info
Title
Improving throughput for small disk requests with proximal I/O
Abstract
This paper introduces proximal I/O, a new technique for improving random disk I/O performance in file systems. The key enabling technology for proximal I/O is the ability of disk drives to retire multiple I/Os, spread across dozens of tracks, in a single revolution. Compared to traditional update-in-place or write-anywhere file systems, this technique can provide a nearly seven-fold improvement in random I/O performance while maintaining (near) sequential on-disk layout. This paper quantifies proximal I/O performance and proposes a simple data layout engine that uses a flash memory-based write cache to aggregate random updates until they have sufficient density to exploit proximal I/O. The results show that with cache of just 1% of the overall disk-based storage capacity, it is possible to service 5.3 user I/O requests per revolution for random updates workload. On an aged file system, the layout can sustain serial read bandwidth within 3% of the best case. Despite using flash memory, the overall system cost is just one third of that of a system with the requisite number of spindles to achieve the equivalent number of random I/O operations.
Year
Venue
Keywords
2011
FAST
file system,o performance,o operation,overall system cost,random disk,improving throughput,aged file system,small disk request,sequential on-disk layout,aggregate random updates,o request,random updates workload
Field
DocType
Citations 
File system,Multipath I/O,Flash memory,I/O scheduling,Cache,Computer science,Parallel computing,Input/output,Throughput,Memory-mapped I/O,Operating system
Conference
16
PageRank 
References 
Authors
0.68
18
3
Name
Order
Citations
PageRank
Jiri Schindler141126.82
Sandip Shete2181.04
Keith A. Smith351765.81