FAILOVER AND LOAD BALANCING

• US 20100185794A1
• Filed: 03/29/2010
• Published: 07/22/2010
• Est. Priority Date: 03/19/2004
• Status: Active Grant

• Current Assignee: Alexander Belyakov, Alexey Drozdov, Mikhail Sennikovsky
• Original Assignee: Alexander Belyakov, Alexey Drozdov, Mikhail Sennikovsky
• Inventors: SENNIKOVSKY, Mikhail, BELYAKOV, Alexander, DROZDOV, Alexey
• Granted Patent: US 7,992,039 B2
• Time in Patent Office: Days
• US Class Current: 710/38
• CPC Class Codes: G06F 3/0601 Interfaces specially adapted for storage systems
• CPC Class Codes: G06F 3/0673 Single storage device
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: H04L 69/18 Multiprotocol handlers, e.g. single devices capable of handling multiple protocols
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06

Abstract

Provided are techniques for static load balancing implemented in a filter driver. The filter driver determines a data quota for each of multiple data paths. The filter driver identifies a maximum number of commands for a target logical unit. The filter driver selects a data path on which to send a packet based on the data quota and the maximum number of commands. Also, provided are techniques for dynamic load balancing implemented in a filter driver. The filter driver determines a data transfer speed for each of multiple data paths. The filter driver updates a load balancing share for each of the multiple data paths based on the data transfer speed of each of the multiple data paths. The filter driver selects a data path on which to send a packet based on the load balancing share of each of the multiple data paths.

Claims

1. A method for static load balancing implemented in a filter driver, wherein the filter driver performs:

determining a data quota for each of multiple data paths;

identifying a maximum number of commands for a target logical unit; and

selecting a data path on which to send a packet based on the data quota and the maximum number of commands.

2. The method of claim 1, wherein the filter driver further performs:

determining a load balancing share associated with each data path in a team; and

determining a mean data length of transmitted packets for each data path.

3. The method of claim 1, wherein the data path is selected using a round robin technique, and wherein packets are sent along the selected data path until at least one of the data quota for the data path is met and until a maximum number of commands is reached.

4. A method for dynamic load balancing implemented in a filter driver, wherein the filter driver performs:

determining a data transfer speed for each of multiple data paths;

updating a load balancing share for each of the multiple data paths based on the data transfer speed of each of the multiple data paths; and

selecting a data path on which to send a packet based on the load balancing share of each of the multiple data paths.

5. The method of claim 4, wherein the data transfer speed is calculated for each of the multiple data paths as a ratio of total data transferred and total time spent on transferring data.

6. The method of claim 4, wherein a frequency at which the data transfer speed is determined is tunable.

7. A system coupled to a network and data storage, comprising:

a host computer;

a storage controller managing Input/Output (I/O) access to the data storage, wherein the storage controller is coupled to the host computer; and

a filter driver capable of determining a data quota for each of multiple data paths, identifying a maximum number of commands for a target logical unit, and selecting a data path on which to send a packet based on the data quota and the maximum number of commands.

8. The system of claim 7, wherein the filter driver further performs:

determining a load balancing share associated with each data path in a team; and

determining a mean data length of transmitted packets for each data path.

9. The system of claim 7, wherein the data path is selected using a round robin technique, and wherein packets are sent along the selected data path until at least one of the data quota for the data path is met and until a maximum number of commands is reached.

10. A system coupled to a network and data storage, comprising:

a host computer;

a storage controller managing Input/Output (I/O) access to the data storage, wherein the storage controller is coupled to the host computer; and

a filter driver capable of determining a data transfer speed for each of multiple data paths, updating a load balancing share for each of the multiple data paths based on the data transfer speed of each of the multiple data paths, and selecting a data path on which to send a packet based on the load balancing share of each of the multiple data paths.

11. The system of claim 10, wherein the data transfer speed is calculated for each of the multiple data paths as a ratio of total data transferred and total time spent on transferring data.

12. The system of claim 10, wherein a frequency at which the data transfer speed is determined is tunable.

13. An article of manufacture comprising a storage medium having stored therein instructions that when executed by a computing device results in the following:

determining a data quota for each of multiple data paths;

identifying a maximum number of commands for a target logical unit; and

selecting a data path on which to send a packet based on the data quota and the maximum number of commands.

14. The article of manufacture of claim 13, the instructions when executed further result in the following:

determining a load balancing share associated with each data path in a team; and

determining a mean data length of transmitted packets for each data path.

15. The article of manufacture of claim 13, wherein the data path is selected using a round robin technique, and wherein packets are sent along the selected data path until at least one of the data quota for the data path is met and until a maximum number of commands is reached.

16. An article of manufacture comprising a storage medium having stored therein instructions that when executed by a computing device results in the following:

determining a data transfer speed for each of multiple data paths;

updating a load balancing share for each of the multiple data paths based on the data transfer speed of each of the multiple data paths; and

selecting a data path on which to send a packet based on the load balancing share of each of the multiple data paths.

17. The article of manufacture of claim 16, wherein the data transfer speed is calculated for each of the multiple data paths as a ratio of total data transferred and total time spent on transferring data.

18. The system of claim 16, wherein a frequency at which the data transfer speed is determined is tunable.