Bug 438760 (rhel6dmloadbal)
| Summary: | kernel dm multipath: Dynamic Load balancing | ||||||
|---|---|---|---|---|---|---|---|
| Product: | Red Hat Enterprise Linux 6 | Reporter: | Kiyoshi Ueda <kueda> | ||||
| Component: | device-mapper-multipath | Assignee: | LVM and device-mapper development team <lvm-team> | ||||
| Status: | CLOSED CURRENTRELEASE | QA Contact: | Barry Donahue <bdonahue> | ||||
| Severity: | high | Docs Contact: | |||||
| Priority: | medium | ||||||
| Version: | 6.0 | CC: | agk, bmarzins, bzeranski, christophe.varoqui, coughlan, dmo, dwysocha, egoggin, heinzm, i-kitayama, jruemker, junichi.nomura, kueda, lmb, ltroan, mbroz, m-ikeda, mikeda, phinchman, prockai, rlerch, syeghiay, tao, tranlan | ||||
| Target Milestone: | beta | Keywords: | FutureFeature | ||||
| Target Release: | 6.0 | ||||||
| Hardware: | All | ||||||
| OS: | Linux | ||||||
| Whiteboard: | |||||||
| Fixed In Version: | device-mapper-multipath-0.4.9-4.el6 | Doc Type: | Enhancement | ||||
| Doc Text: | Story Points: | --- | |||||
| Clone Of: | Environment: | ||||||
| Last Closed: | 2010-11-10 20:07:34 UTC | Type: | --- | ||||
| Regression: | --- | Mount Type: | --- | ||||
| Documentation: | --- | CRM: | |||||
| Verified Versions: | Category: | --- | |||||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |||||
| Cloudforms Team: | --- | Target Upstream Version: | |||||
| Embargoed: | |||||||
| Bug Depends On: | |||||||
| Bug Blocks: | 425967, 554559, 563255 | ||||||
| Attachments: |
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Description
Kiyoshi Ueda
2008-03-24 22:02:51 UTC
*** Bug 199767 has been marked as a duplicate of this bug. *** *** Bug 446523 has been marked as a duplicate of this bug. *** Could you please add the RHEL6 feature template. This is currently a public (unrestricted) bugzilla. Do you want it to be Confidential? Here is the RHEL6 feature template.
NEC is fine that this bugzilla is public.
1. Feature Overview:
a. Name of feature:
device-mapper multipath dynamic load balancing
b. Feature Description:
2. Feature Details:
a. Architectures:
i686, x86_64, ia64
b. Bugzilla Dependencies:
c. Drivers or hardware dependency:
d. Upstream acceptance information:
Patch submitted to upstream
e. External links:
Request-based device-mapper:
http://lkml.org/lkml/2008/9/12/100
Dynamic Load Balancer:
http://marc.info/?l=dm-devel&m=122123098803731&w=2
f. Priority (S,H,M,L): H
g. Target Release Date:
3. Business Justification:
a. Why is this feature needed?
Current version of dm-multipath only supports static load-balancing
with round-robin and not optimized for various loads.
b. What hardware does this enable?
High-speed FC storage
c. Forecast, volume or high end platform?
d. Any configuration info?
e. Are there other dependencies (drivers).
4. Primary contact at Red Hat, email, phone (chat)
Larry Troan
ltroan
919-754-4196
5. Primary contact at Partner, email, phone (chat)
Kiyoshi Ueda
k-ueda.nec.com
Jun'ichi Nomura
j-nomura.nec.com
Created attachment 332343 [details]
patch for "Least pending IO" dynamic load balancing policy
Attached is the patch for "Least pending IO" dynamic load balancing policy
Attached patch provides "Least pending IO" dynamic load balancing policy for
device mapper multipath. This load balancing policy considers the
number of unserviced requests pending on a path and selects the path with least
count for pending service request.
We find this policy more useful especially when the SAN environment has
heterogeneous components. Ex, when there is one 8GB HBA and one 2GB HBA
connected to the same server, 8GB HBA could be utilized better with this
algorithm.
Can we have this patch included in RHEL6?
Thanks.
*** Bug 437587 has been marked as a duplicate of this bug. *** These have been included in the 2.6.31, so it will be in RHEL 6: config DM_MULTIPATH_QL "I/O Path Selector based on the number of in-flight I/Os" This path selector is a dynamic load balancer which selects the path with the least number of in-flight I/Os. config DM_MULTIPATH_ST "I/O Path Selector based on the service time" This path selector is a dynamic load balancer which selects the path expected to complete the incoming I/O in the shortest time. We would appreciate hearing test results and feedback on these. Vijay, Do these meet your needs? If not, please re-submit to dm-devel list and explain why. Tom, Vijay is no longer with HP. I'll have to alert the DM team to update this. Paul, does anyone at HP have any feedback on this BZ for 6.0? Ueda-san, Red Hat has asked that you quickly comment whether NEC has verified this fix with a comment in this bug and by setting NEC in the "partner" field of this bug. Dohmo arigato gozai-masu. Barry, HP submission of this FEAT was originally done by a team that is now disbanded. While we would still like this feature for all customers, we no longer have resources to test it (request is 2.5 years old). We will have to leverage off of what other partners, such as NEC, produce as results. Thanks, Paul H. NEC has confirmed that 2 dynamic load balancers, queue-length and service-time, are included in RHEL6.0 RC1. This bug has been fixed. Tom, per comment #10, Vijay is no longer with HP. NEC has verified this fix per comment #15. Can we set status to VERIFIED please. Red Hat Enterprise Linux 6.0 is now available and should resolve the problem described in this bug report. This report is therefore being closed with a resolution of CURRENTRELEASE. You may reopen this bug report if the solution does not work for you. |