Electrical Engineering
      and Computer Sciences

Electrical Engineering and Computer Sciences

COLLEGE OF ENGINEERING

UC Berkeley

Disk Caching in Large Databases and Timeshared Systems

Barbara Tockey Zivkov and Alan Jay Smith

EECS Department
University of California, Berkeley
Technical Report No. UCB/CSD-96-913
September 1996

http://www.eecs.berkeley.edu/Pubs/TechRpts/1996/CSD-96-913.pdf

We present the results of a variety of trace-driven simulations of disk cache design. Our traces come from a variety of mainframe timesharing and database systems in production use. We compute miss ratios, run lengths, traffic ratios, cache residency times, degree of memory pollution and other statistics for a variety of designs, varying block size, prefetching algorithm and write algorithm. We find that for this workload, sequential prefetching produces a significant (about 20%) but still limited improvement in the miss ratio, even using a powerful technique for detecting sequentiality. Copy-back writing decreased write traffic relative to write-through; periodic flushing of the dirty blocks increased write traffic only slightly compared to pure write-back, and then only for large cache sizes. Write-allocate had little effect compared to no-write-allocate. Block sizes of over a track don't appear to be useful. Limiting cache occupancy by a single processor transaction appears to have little effect. This study is unique in the variety and quality of the data used in the studies.


BibTeX citation:

@techreport{Zivkov:CSD-96-913,
    Author = {Zivkov, Barbara Tockey and Smith, Alan Jay},
    Title = {Disk Caching in Large Databases and Timeshared Systems},
    Institution = {EECS Department, University of California, Berkeley},
    Year = {1996},
    Month = {Sep},
    URL = {http://www.eecs.berkeley.edu/Pubs/TechRpts/1996/5812.html},
    Number = {UCB/CSD-96-913},
    Abstract = {We present the results of a variety of trace-driven simulations of disk cache design. Our traces come from a variety of mainframe timesharing and database systems in production use. We compute miss ratios, run lengths, traffic ratios, cache residency times, degree of memory pollution and other statistics for a variety of designs, varying block size, prefetching algorithm and write algorithm. We find that for this workload, sequential prefetching produces a significant (about 20%) but still limited improvement in the miss ratio, even using a powerful technique for detecting sequentiality. Copy-back writing decreased write traffic relative to write-through; periodic flushing of the dirty blocks increased write traffic only slightly compared to pure write-back, and then only for large cache sizes. Write-allocate had little effect compared to no-write-allocate. Block sizes of over a track don't appear to be useful. Limiting cache occupancy by a single processor transaction appears to have little effect. This study is unique in the variety and quality of the data used in the studies.}
}

EndNote citation:

%0 Report
%A Zivkov, Barbara Tockey
%A Smith, Alan Jay
%T Disk Caching in Large Databases and Timeshared Systems
%I EECS Department, University of California, Berkeley
%D 1996
%@ UCB/CSD-96-913
%U http://www.eecs.berkeley.edu/Pubs/TechRpts/1996/5812.html
%F Zivkov:CSD-96-913