How does rr_min_io affect performance with device-mapper-multipath on Red Hat Enterprise Linux?
Issue
- poor SAN IO perf on BL460 vs Solaris10
- I/O throughput is not evenly balanced across all paths in a multipath device
- Our SAN vendor requesting us to enforce rr_min_io from a standard 100 to 1000 (10x more). rr_min_io should not be dictated by storage manufacturer/maker should it?
Environment
- Red Hat Enterprise Linux (RHEL) including:
- Red Hat Enterprise Linux 5 (RHEL5)
- Red Hat Enterprise Linux 6 (RHEL6)
- device-mapper-multipath managing SAN-based storage with various values of rr_min_io.
Subscriber exclusive content
A Red Hat subscription provides unlimited access to our knowledgebase, tools, and much more.