Optimized non-volatile storage systems

• US 7,926,720 B2
• Filed: 07/02/2008
• Issued: 04/19/2011
• Est. Priority Date: 07/28/2004
• Status: Active Grant

• Current Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Original Assignee: SanDisk Corporation (Western Digital Corporation)
• Inventors: Pinto, Yosi, Brewer, Wesley G., Tomlin, Andrew, Holtzman, Micky, Elhamias, Reuven
• Primary Examiner(s): Labaze; Edwyn
• Application Number:
  US12/166,533
• Publication Number:
  US 20080270639A1
• Time in Patent Office: 1,021 Days
• Field of Search: 235/451, 235/492, 235/487, 235/380, 713/500, 713/600
• US Class Current: 235/451
• CPC Class Codes: G06F 13/385 for adaptation of a particular data processing system to different peripheral devices
• CPC Class Codes: G06F 3/0607 by facilitating the process of upgrading existing storage systems, e.g. for improving compatibility between host and storage device
• CPC Class Codes: G06F 3/0632 by initialisation or re-initialisation of storage systems
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

A memory card that adapts its operation according to the application to which it applied or the conditions under which it is operated. This allows the card to dynamical self optimize. In a first set of embodiments, the card uses host profiling where it will learn about the host during host-card interactions and the card'"'"'s controller will optimize its algorithms accordingly. In another set of embodiments, the host and card will report to one another their capabilities for a quality of service negotiation. A further set of embodiments allows the storage device to memorize access sequences issued by the host under various predefined conditions, such as host reset or a power on boot sequence. The storage device can use this information to optimize operation for the expected commands. On deviation from an expected sequence, the device would memorize the new command sequence and save it, thus operating in a self-adaptive manner.

Claims

1. A method of operating an electronic circuit card, the card including a controller for managing the card content and the interactions between the card and a host to which it is connected according to a set of algorithms, comprising:

monitoring of host-card interactions by the controller;

based on said monitoring, determining characteristics of the host-card interactions; and

optimizing said algorithms based on said host-card interactions,

wherein the controller maintains a card system clock and wherein said monitoring comprises;

incrementing a count in response to transactions on a bus whereby signals are exchanged between the card and the host; and

calculating a clock rate of the bus based on said count and the card system clock.

2. The method of claim 1, wherein said optimizing said algorithms comprises:

adjusting the rate of the card system clock based on the bus clock rate.

3. A method of operating an electronic circuit card, the card including a controller for managing the card content and the interactions between the card and a host to which it is connected according to a set of algorithms, comprising:

monitoring a plurality of host-card interactions by the controller, wherein said monitoring comprises measuring the amount of time to transfer a specified amount of data between the card and the host;

based on said monitoring, determining characteristics of the host-card interactions, wherein said characteristics comprise the read and write transfer rates of the host; and

using said controller to optimize at least one algorithm of said set of algorithms based on said host-card interactions, wherein said optimizing said algorithms comprises;

adjusting the rate of reading data from and writing data a non-volatile memory of the card based on the read and write transfer rates of the host.

4. A method of operating an electronic circuit card, the card including a controller for managing the card content and the interactions between the card and a host to which it is connected according to a set of algorithms, comprising:

monitoring of host-card interactions by the controller;

based on said monitoring, determining characteristics of the host-card interactions;

optimizing said algorithms based on said host-card interactions;

monitoring conditions external the card; and

optimizing said algorithms based on said conditions external the card.

5. The method of claim 4, wherein said optimizing said algorithms comprises:

adjusting a clock rate based on the external conditions.

6. A method of operating an electronic circuit card, the card including a controller for managing the card content and the interactions between the card and a host to which it is connected according to a set of algorithms, comprising:

the host communicating its capabilities to the card;

the host transmitting to the card a request for the card'"'"'s capabilities;

in response to said request, the card communicating its capabilities to the host;

the host sending a first request to the card to adjust the set of algorithms for a first application according to the capabilities of the host and the card;

the card adjusting the set algorithms in response to the first request;

subsequent to said sending a first request, the host sending a second request to the card to adjust the set of algorithms for a second application according to the capabilities of the host and the card; and

the card adjusting the set algorithms in response to the second request.

7. The method of claim 6, further comprising:

prior to the host communicating its capabilities to the card and the host transmitting to the card a request for the card'"'"'s capabilities, connecting the card to the host;

the host sending a reset signal to card; and

in response to the reset signal, the card sending a ready signal to the host.

8. The method of claim 6, wherein the host capabilities include the host profile for accessing the card.

9. The method of claim 6, wherein the card capabilities include read speed.

10. The method of claim 6, wherein the card capabilities include write speed.

11. The method of claim 6, wherein the host capabilities include write/read maximum speed.