article Frangipani: a scalable distributed file system Share on Authors: Chandramohan A. Thekkath Systems Research Center, Digital Equipment Corporation, 130 Lytton Ave, Palo Alto, CA Systems Research Center, Digital Equipment Corporation, 130 Lytton Ave, Palo Alto, CAView Profile , Timothy Mann Systems Research Center, Digital Equipment Corporation, 130 Lytton Ave, Palo Alto, CA Systems Research Center, Digital Equipment Corporation, 130 Lytton Ave, Palo Alto, CAView Profile , Edward K. Lee Systems Research Center, Digital Equipment Corporation, 130 Lytton Ave, Palo Alto, CA Systems Research Center, Digital Equipment Corporation, 130 Lytton Ave, Palo Alto, CAView Profile Authors Info & Claims ACM SIGOPS Operating Systems ReviewVolume 31Issue 5Dec. 1997 pp 224–237https://doi.org/10.1145/269005.266694Online:01 October 1997Publication History 250citation3,355DownloadsMetricsTotal Citations250Total Downloads3,355Last 12 Months141Last 6 weeks25 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteGet Access

Extensive caching is a key feature of the Echo distributed file system. Echo client machines maintain coherent caches of file and directory data and properties, with write-behind (delayed write-back) ofallcached information. Echo specifies ordering constraints on this write-behind, enabling applications to store and maintain consistent data structures in the file system even when crashes or network faults prevent some writes from being completed. In this paper we describe the Echo cache's coherence and ordering semantics, show how they can improve the performance and consistency of applications, explain how they are implemented. We also discuss the general problem of reliably notifying applications and users when write-behind is lost; we addressed this problem as part of the Echo design, but did not find a fully satisfactory solution.

We have incorporated on-line data compression into the low levels of a log-structured file system (Rosenblum's Sprite IFS).Each block of data or meta-data is compressed as it is written to the disk and decompressed as it is read.The log-structuring overcomes the problems of allocation and fragmentation for variable-sized blocks.We observe compression factors ranging from 1.6 to 2.2, using algorithms running from 1.7 to 0.4 MBytes per second in software on a DECstation 5000/200.System performance is degraded by a few percent for normal activities (such as compiling or editing), and as much as a factor of 1.6 for file system intensive operations (such as copying multi-megabyte files).Hardware compression devices mesh well with this design.Chips are already available that operate at speeds exceeding disk transfer rates, which indicates that hardware compression would not only remove the performance degradation we observed, but might well increase the effective dkk transfer rate beyond that obtainable from a system without compression.

Naming is an important aspect of distributed system design. A naming system allows users and programs to assign character-string names to objects, and subsequently use the names to refer to those objects. With the interconnection of clusters of computers by wide-area networks and internetworks, the domain over which naming systems must function is growing to encompass the entire world. In this paper we address the problem of a global naming system, proposing a three-level naming architecture that consists of global, administrational, and managerial naming mechanisms, each optimized to meet the performance, reliability, and security requirements at its own level. We focus in particular on a decentralized approach to the lower levels, in which naming is handled directly by the managers of the named objects. Client-name caching and multicast are exploited to implement name mapping with almost optimum performance and fault tolerance. We also show how the naming system can be made secure. Our conclusions are bolstered by experience with an implementation in the V distributed operating system.