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:
Apr. 28, 2020
Filed:
Aug. 02, 2017
Emc Ip Holding Company Llc, Hopkinton, MA (US);
Suraj Brahma Raju, Issaquah, WA (US);
Ronald Steinke, Tacoma, WA (US);
EMC IP Holding Company LLC, Hopkinton, MA (US);
Abstract
Implementations are provided herein for a node among a cluster of nodes to maintain copies of its journal both locally and on a buddy node. Each copy of the journal can be associated with a validity bit and a clean bit that can be provided as inputs to a journal mirror state machine that can be used to maintain consistency between local copies of the journal and mirrored copies of the journal. The node can operate in a read-only mode or a read-write mode, whereby operating in read-only mode prevents changes to the local journal. The status of the mirror copy of the journal can be established in a link status depending on its availability. The journal can then transition between various states of the state machine upon triggering events that change the link status or the mode of the node. It can be appreciated that the transitioning among states of the state machine can provide crash-consistency for the filesystem during operation.