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. 07, 2015
Filed:
Mar. 30, 2012
David W. Harvey, Newton, MA (US);
Henry Austin Spang, Iv, Hopkinton, MA (US);
David W. Harvey, Newton, MA (US);
Henry Austin Spang, IV, Hopkinton, MA (US);
EMC Corporation, Hopkinton, MA (US);
Abstract
A method, performed at a first storage processor (SP) connected to a mirroring second SP, includes (a) receiving a write command at the first SP from a host directed to a particular address of a data storage array, (b) identifying a reference in a first cache that is uniquely associated with the particular address, the reference having a token count field, (c) determining whether the reference is synchronized with a corresponding reference in a second cache, and (d) if the reference is synchronized with the corresponding reference, then (1) performing a cache write operation on a cache page pointed to by the reference if the reference stores a maximum token count value and (2) otherwise, sending a token request message from the first SP to the second SP over a cache mirroring bus to request a token from the second SP prior to performing the cache write operation.