Summary: Appears in Proc. Third Symposium on Operating Systems Design and Implementation, February 1999.
Virtual Log Based File Systems for a Programmable Disk #
Randolph Y. Wang + Thomas E. Anderson # David A. Patterson +
Abstract
In this paper, we study how to minimize the la­
tency of small synchronous writes to disks. The
basic approach is to write to free sectors that are
near the current disk head location by leveraging
the embedded processor core inside the disk. We
develop a number of analytical models to demon­
strate the performance potential of this approach.
We then present the design of a virtual log, a log
whose entries are not physically contiguous, and a
variation of the log­structured file system based on
this approach. The virtual log based file systems can
e#ciently support small synchronous writes with­
out extra hardware support while retaining the ad­
vantages of LFS including its potential to support
transactional semantics. We compare our approach
against traditional update­in­place and logging sys­

Source: Anderson, Tom - Department of Computer Science and Engineering, University of Washington at Seattle

Collections: Computer Technologies and Information Sciences