System and method for populating a cache using behavioral adaptive policies

• US 20090182836A1
• Filed: 01/16/2008
• Published: 07/16/2009
• Est. Priority Date: 01/16/2008
• Status: Active Grant

• Current Assignee: NetApp, Inc.
• Original Assignee: NetApp, Inc.
• Inventors: Cree, Mark U., Dahl, Gregory A., Aviles, Joaquin J.
• Granted Patent: US 8,805,949 B2
• Time in Patent Office: Days
• US Class Current: 709/213
• CPC Class Codes: H04L 41/08 Configuration management of networks or network elements address allocation H04L61/50
• CPC Class Codes: H04L 41/0893 Assignment of logical groups to network elements
• CPC Class Codes: H04L 41/0894 Policy-based network configuration management
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1014 based on the content of a request
• CPC Class Codes: H04L 67/1025 Dynamic adaptation of the criteria on which the server selection is based
• CPC Class Codes: H04L 67/564 Enhancement of application control based on intercepted application data
• CPC Class Codes: H04L 67/568 Storing data temporarily at an intermediate stage, e.g. caching
• CPC Class Codes: H04L 67/5682 Policies or rules for updating, deleting or replacing the stored data

Abstract

A method, system and program are disclosed for accelerating data storage in a cache appliance cluster that transparently monitors NFS and CIFS traffic between clients and NAS subsystems and caches files using dynamically adjustable cache policies which populate the storage cache using behavioral adaptive policies that are based on analysis of clients-filers transaction patterns and network utilization, thereby improving access time to the data stored on the disk-based NAS filer (group) for predetermined applications.

Claims

1. A standalone cache unit for adaptively caching data operations requested from one or more networked data storage devices by one or more remote clients, the standalone cache unit comprising:

a cache memory for caching data that is requested by a remote client;

a packet processor coupled to the cache memory and to one or more I/O ports for transparently splicing connections between the data storage devices and remote clients, where the packet processor inspects network protocol traffic state parameters received on the I/O ports to determine if a request from a remote client can be serviced by the standalone cache unit; and

an adaptive cache control module for controlling caching operations in the cache memory which uses a default cache engine policy and a user-specified cache profile for selectively adjusting the default cache engine policy in accordance with business requirements of the user.

2. The standalone cache unit of claim 1, where the user-specified cache profile provides preferential access to the cache memory for files from a user-specified application data set.

3. The standalone cache unit of claim 1, where the user-specified cache profile provides preferential access to the cache memory for files from a user-specified application data set in accordance with a predetermined schedule.

4. The standalone cache unit of claim 1, where the user-specified cache profile provides preferential access to the cache memory for files from a client located at a predetermined IP address.

5. The standalone cache unit of claim 1, where the user-specified cache profile provides preferential access to the cache memory for files from a predetermined location in a specified networked data storage device.

6. The standalone cache unit of claim 1, where the user-specified cache profile provides preferential access to the cache memory for a predetermined set of files that are identified by one or more file path components, such as NAS subsystem, filer, volume, path, directory, name, extension and size.

7. The standalone cache unit of claim 1, comprising a cluster of two or more cache appliances for caching data operations requested from one or more networked data storage devices by one or more remote clients, the cluster comprising:

an appliance cache memory at each cache appliance for caching data that is requested by a remote client;

an appliance packet processor at each cache appliance coupled to the appliance cache memory in said cache appliance and to one or more I/O ports for transparently splicing connections between the data storage devices and remote clients, where the appliance packet processor inspects network protocol traffic state parameters received on the I/O ports to determine if a request from a remote client can be serviced by the cluster; and

a connection interface for connecting the two or more cache appliances over a cluster bus in a private network to form a cohesive memory pool from the appliance cache memories in the two or more cache appliances.

8. The standalone cache unit of claim 1, where the default cache engine policy comprises a least recently used with dual time reference algorithm aided with greedy dual size frequency algorithm.

9. The standalone cache unit of claim 1, where the packet processor executes software that transparently monitors NFS and CIFS traffic between remote clients and NAS subsystems.

10. A method for adaptively caching data operations, comprising:

receiving at a standalone cache unit a request from a remote client to perform a specified data operation at one or more networked data storage devices;

inspecting packet parameters in each TCP/IP stack layer associated with the request to determine if the request can be serviced by a cache memory located at the standalone cache unit;

performing the specified data operation at the cache memory if the request can be serviced by the standalone cache unit;

populating the cache memory with a default cache engine policy; and

modifying the default cache engine policy with a user-specified cache profile for selectively adjusting the default cache engine policy in accordance with business requirements of the user.

11. The method of claim 10, where the user-specified cache profile provides preferential access to the cache memory for files from a user-specified application data set.

12. The method of claim 10, where the user-specified cache profile provides preferential access to the cache memory for files from a user-specified application data set in accordance with a predetermined schedule.

13. The method of claim 10, where the user-specified cache profile provides preferential access to the cache memory for files from a client located at a predetermined IP address.

14. The method of claim 10, where the user-specified cache profile provides preferential access to the cache memory for files from a predetermined location in a specified networked data storage device.

15. The method of claim 10, where the user-specified cache profile provides preferential access to the cache memory for a predetermined set of files that are identified by one or more file path components, such as NAS subsystem, filer, volume, path, directory, name, extension and size.

16. The method of claim 10, where the user-specified cache profile provides preferential access to the cache memory for one or more specified remote clients using one or more predetermined schedules that specify when each remote client has preferential access.

17. The method of claim 10, where the default cache engine policy comprises a least recently used with dual time reference algorithm aided with greedy dual size frequency algorithm.

18. A network cache appliance for accelerating read and write requests from one or more storage clients for one or more files residing at one or more networked storage devices, comprising:

a tiered memory cache system for adaptively caching data to provide low-latency access in responding to read and write requests using dynamically adjustable cache policies that reflect the data caching requirements that change over time; and

a packet inspection module for transparently inspecting a read or write request sent using an IP-based network protocol to determine if the request should be passed to the tiered memory cache system or forwarded to a networked storage device for further processing.

19. The network cache appliance of claim 18, where the tiered memory cache system comprises:

a dynamic and non-volatile cache memory for providing low-latency access in responding to read and write requests; and

an adaptive cache controller for controlling caching operations in the cache memory which uses a default cache engine policy and a user-specified cache profile for selectively adjusting the default cache engine policy in accordance with business requirements of the user.

20. The network cache appliance of claim 19, where the user-specified cache profile provides preferential access to the cache memory for files from a user-specified application data set in accordance with a predetermined schedule.