@TechReport{moyer:scalable-tr, author = {Steven A. Moyer and V.~S. Sunderam}, title = {Scalable Concurrency Control for Parallel File Systems}, year = {1995}, month = {February}, number = {CSTR-950202}, institution = {Emory University}, later = {moyer:scalable}, URL = {ftp://ftp.mathcs.emory.edu/pub/cstr/CSTR950202.ps}, keywords = {parallel I/O, parallel file system, pario-bib}, abstract = {Parallel file systems employ data declustering to increase I/O throughput. As a result, a single read or write operation can generate concurrent data accesses on multiple storage devices. Unless a concurrency control mechanism is employed, familiar file access semantics are likely to be violated. This paper details the transaction-based concurrency control mechanism implemented in the PIOUS parallel file system. Performance results are presented demonstrating that sequential consistency semantics can be provided without loss of system scalability.}, comment = {They describe {\em volatile transactions\/} as a way of providing the appopriate sequential consistency among file-read and -write operations (a feature not provided by most file systems). Their PIOUS library implements these transactions with strict 2-phase locking. They show some performance results, though only on a limited and relatively simple benchmark. If nothing else this paper reminds us all that atomicity of file-read and -write requests should be available to the user (eg, note how they are optional in Vesta). Published as moyer:scalable.} }