METHOD AND SYSTEM FOR MULTI-LAYER DIFFERENTIAL LOAD BALANCING IN TIGHTLY COUPLED CLUSTERS

• US 20130198424A1
• Filed: 01/31/2012
• Published: 08/01/2013
• Est. Priority Date: 01/31/2012
• Status: Active Grant

• Current Assignee: Veritas Technologies, LLC (Whitehouse Group Ltd.)
• Original Assignee: Symantec Corporation (NortonLifeLock Inc.)
• Inventors: Dash, Prasanta, Randhawa, Amarinder Singh, Buddhi, Madhav, Yalamanchili, Chaltanya
• Granted Patent: US 9,158,714 B2
• Time in Patent Office: Days
• US Class Current: 710/74
• CPC Class Codes: G06F 13/14 Handling requests for interconnection or transfer
• CPC Class Codes: G06F 13/385 for adaptation of a particular data processing system to different peripheral devices

Abstract

A method and system for load balancing. The method includes discovering each of a plurality of hosts in a cluster, wherein the plurality of hosts is configured for accessing a LUN of a storage system through a storage network fabric. Global input/output (I/O) load characteristics are collected for each of the plurality of hosts at the device and/or volume level. A selected host is determined for processing an I/O originating at the local host, wherein the host is selected based on a current set of the global I/O load characteristics.

Claims

1. A computer implemented method for load balancing, comprising:

at a volume manager of a local host, discovering each of a plurality of hosts in a cluster, wherein said plurality of hosts is configured for accessing a LUN of a storage system through a storage network fabric;

at said volume manager, collecting global I/O load characteristics for each of a plurality of hosts in said cluster; and

determining a selected host for processing an I/O originating at said local host based on a current set of said global I/O load characteristics.

2. The computer implemented method of claim 1, wherein said selecting said local or remote host comprises:

determining to ship said I/O from said local host based on said current set of said global I/O load characteristics to said selected host comprising a remote host; and

selecting said remote host from one or more remote hosts based on favorable differential I/O load balancing statistics determined in comparison to said local host; and

redirecting said I/O from said first host to said remote host.

3. The computer implemented method of claim 1, wherein said global I/O load characteristics is taken from a group consisting of:

I/O throughput;

I/O response time;

network latency between a corresponding remote host and said local host;

I/O load at each of said plurality of hosts; and

resource availability.

4. The computer implemented method of claim 1, further comprising:

determining to process said I/O at said local node based on said current set of said global I/O load characteristics, wherein said selected host comprises said local node;

at a multi-pathing driver of said local host, performing local load balancing to assign said I/O to a selected path of one or more local communication paths accessing said LUN.

5. The computer implemented method of claim 1, wherein said determining a selected host further comprises:

determining said selected host having the best I/O load characteristics for an I/O having a high priority.

6. The computer implemented method of claim 1, wherein said determining a selected host further comprises:

determining said selected host having the poorest I/O load characteristics for said I/O having a low priority.

7. The computer implemented method of claim 1, further comprising:

collecting values of said current set of said global statistics in a delayed and amortized fashion for said plurality of hosts.

8. The computer implemented method of claim 1, further comprising:

providing a plurality of default values for said global statistics.

9. A computer system, comprising:

a processor; and

memory coupled to said processor and having stored therein instructions that, if executed by said computer system, cause said computer system to execute a method for load balancing, comprising;

at a volume manager, collecting global I/O load characteristics for each of a plurality of hosts in a cluster, wherein said plurality of hosts are configured for accessing a LUN of a storage system through a storage network fabric; and

determining a selected host for processing an I/O originating at said local host based on a current set of said global I/O load characteristics.

10. The computer system of claim 9, wherein said selecting said local or remote host in said method comprises:

determining to ship said I/O from said local host based on said current set of said global I/O load characteristics to said selected host comprising a remote host; and

selecting said remote host from one or more remote hosts based on favorable differential I/O load balancing statistics determined in comparison to said local host; and

redirecting said I/O from said first host to said remote host.

11. The computer system of claim 9, wherein in said method said global I/O load characteristics is taken from a group consisting of:

I/O throughput;

I/O response time;

network latency between a corresponding remote host and said local host;

I/O load at each of said plurality of hosts; and

resource availability.

12. The computer system of claim 9, wherein said method further comprises:

determining to process said I/O at said local node based on said current set of said global I/O load characteristics, wherein said selected host comprises said local node;

at a multi-pathing driver of said local host, performing local load balancing to assign said I/O to a selected path of one or more local communication paths accessing said LUN.

13. The non-transitory computer-readable storage medium having computer-executable instructions for causing a computer system to perform a method for load balancing, comprising:

at a volume manager of a local host, collecting global I/O load characteristics for each of a plurality of hosts in a cluster, wherein said plurality of hosts are configured for accessing a LUN of a storage system through a storage network fabric; and

determining a selected host for processing an I/O originating at said local host based on a current set of said global I/O load characteristics.

14. The computer-readable storage medium of claim 13, wherein said selecting said local or remote host in said method comprises:

determining to ship said I/O from said local host based on said current set of said global I/O load characteristics to said selected host comprising a remote host; and

selecting said remote host from one or more remote hosts based on favorable differential I/O load balancing statistics determined in comparison to said local host; and

redirecting said I/O from said first host to said remote host.

15. The computer-readable storage medium of claim 13, wherein in said method said global I/O load characteristics is taken from a group consisting of:

I/O throughput;

I/O response time;

network latency between a corresponding remote host and said local host;

I/O load at each of said plurality of hosts; and

resource availability.

16. A computer-readable storage medium of claim 13, wherein said method further comprises:

determining to process said I/O at said local node based on said current set of said global I/O load characteristics, wherein said selected host comprises said local node;

at a multi-pathing driver of said local host, performing local load balancing to assign said I/O to a selected path of one or more local communication paths accessing said LUN.

17. The computer-readable storage medium of claim 13, wherein in said method said determining a selected host further comprises:

determining said selected host having the best I/O load characteristics for an I/O having a high priority.

18. The computer-readable storage medium of claim 13, wherein in said method said determining a selected host further comprises:

determining said selected host having the poorest I/O load characteristics for said I/O having a low priority.

19. The computer-readable storage medium of claim 13, wherein said method further comprises:

collecting values of said current set of said global statistics in a delayed and amortized fashion for said plurality of hosts.

20. The computer-readable storage medium of claim 13, wherein said method further comprises:

providing a plurality of default values for said global statistics.