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:
Jul. 13, 2021
Filed:
Jan. 10, 2019
Western Digital Technologies, Inc., San Jose, CA (US);
Noga Deshe, Raanana, IL;
Gadi Vishne, Petach-Tikva, IL;
WESTERN DIGITAL TECHNOLOGIES, INC., Sa, CA (US);
Abstract
Exemplary methods and apparatus are disclosed to select data evacuation policies for use by a solid state device (SSD) to relocate data from an upper (high performance) memory tier to a lower memory tier. The upper tier may be, e.g., a single-layer cell (SLC) tier of a multi-tier NAND memory, whereas the lower tier may be, e.g., a triple-layer cell (TLC) or a quad-level cell (QLC) tier of the NAND memory. In one example, the SSD monitors its recent input/output (I/O) command history. If a most recent command was a read command, the SSD performs a 'lazy' evacuation procedure to evacuate data from the upper tier storage area to the lower tier storage area. Otherwise, the SSD performs a 'greedy' or “eager” evacuation procedure to evacuate the data from the upper tier to the lower tier. Other evacuation selection criteria are described herein based, e.g., upon predicting upcoming I/O commands.