John K. Ousterhout and Frederick Douglis

EECS Department, University of California, Berkeley

Technical Report No. UCB/CSD-88-467

1988

CPU speeds are improving at a dramatic rate, while disk speeds are not. This technology shift suggests that many engineering and office applications may become so I/O-limited that they cannot benefit from further CPU improvements. This paper discusses several techniques for improving I/O performance, including caches, battery-backed-up caches, and cache logging. We then examine in particular detail an approach called log-structured file systems, where the file system's only representation on disk is in the form of an append-only log. Log-structured file systems potentially provide order-of-magnitude improvements in write performance. When log-structured file systems are combined with arrays of small disks (which provide high bandwidth) and large main-memory file caches (which satisfy most read accesses), we believe it will be possible to achieve 1000-fold improvements in I/O performance over today's systems.

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BibTeX citation:

@techreport{Ousterhout:CSD-88-467,
    Author= {Ousterhout, John K. and Douglis, Frederick},
    Title= {Beating the I/O Bottleneck: A Case for Log-Structured File Systems},
    Year= {1988},
    Month= {Oct},
    Url= {http://www2.eecs.berkeley.edu/Pubs/TechRpts/1988/5760.html},
    Number= {UCB/CSD-88-467},
    Abstract= {CPU speeds are improving at a dramatic rate, while disk speeds are not. This technology shift suggests that many engineering and office applications may become so I/O-limited that they cannot benefit from further CPU improvements. This paper discusses several techniques for improving I/O performance, including caches, battery-backed-up caches, and cache logging. We then examine in particular detail an approach called log-structured file systems, where the file system's only representation on disk is in the form of an append-only log. Log-structured file systems potentially provide order-of-magnitude improvements in write performance. When log-structured file systems are combined with arrays of small disks (which provide high bandwidth) and large main-memory file caches (which satisfy most read accesses), we believe it will be possible to achieve 1000-fold improvements in I/O performance over today's systems.},
}

EndNote citation:

%0 Report
%A Ousterhout, John K. 
%A Douglis, Frederick 
%T Beating the I/O Bottleneck: A Case for Log-Structured File Systems
%I EECS Department, University of California, Berkeley
%D 1988
%@ UCB/CSD-88-467
%U http://www2.eecs.berkeley.edu/Pubs/TechRpts/1988/5760.html
%F Ousterhout:CSD-88-467