The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 13, 2012
Filed:
Dec. 01, 2003
Yasushi Saito, Mountain View, CA (US);
Christos Karamanolis, Los Gatos, CA (US);
Yasushi Saito, Mountain View, CA (US);
Christos Karamanolis, Los Gatos, CA (US);
Hewlett-Packard Development Company, L.P., Houston, TX (US);
Abstract
The invention is a system for and a method of maintaining namespace consistency in a wide-area file system. In one embodiment, a wide-area file system has a plurality of replicas for a file. Each replica of a file and parent directories for the file are at a node. An update to a replica of the file is propagated to other replicas of the file. In response to receiving a propagated update to a replica at a node, the replica for the file at the node is updated. A directory operation (e.g., rename, link or unlink) may affect a backpointer for a replica. When a backpointer for a replica at a node is not consistent with the parent directories for the replica at the node, the the parent directories are modified to be consistent with the backpointer. A modification may be performed at a node while an earlier inconsistent modification may be ignored. As a result, consistency is maintained among the replicas.