[Pacemaker] resources not rebalancing

[Patrick Hemmer]

*From: *Andrew Beekhof <andrew at beekhof.net>
*Sent: * 2014-06-11 02:36:15 EDT
*To: *The Pacemaker cluster resource manager <pacemaker at oss.clusterlabs.org>
*Subject: *Re: [Pacemaker] resources not rebalancing

> On 11 Jun 2014, at 3:44 pm, Patrick Hemmer <pacemaker at feystorm.net> wrote:
>
>>> Right. But each node still has 4998000+ units with which to accommodate something that only requires 10000.
>>> Thats about 0.2% of the remaining capacity, so wherever it starts, its hardly making a dint.
>>>
>> You're thinking of the 'utilization' placement strategy.
> If something is "out of balance" by 0.2%... thats still quite balanced.

I agree, but that's not how the balanced strategy is documented as
working. It says resources are balanced based on the amount of free
capacity on each node, not based on approximate percentages.
However, to nullify this argument, I adjusted the numbers:
    # crm_simulate -URL

    Current cluster status:
    Online: [ i-053f1f59 i-083f1f54 i-093f1f55 ]

     dummy1    (ocf::pacemaker:Dummy):    Started i-053f1f59
     Clone Set: dummy2-clone [dummy2] (unique)
         dummy2:0    (ocf::pacemaker:Dummy):    Started i-053f1f59
         dummy2:1    (ocf::pacemaker:Dummy):    Started i-083f1f54
         dummy2:2    (ocf::pacemaker:Dummy):    Started i-093f1f55
         dummy2:3    (ocf::pacemaker:Dummy):    Started i-083f1f54
         dummy2:4    (ocf::pacemaker:Dummy):    Started i-093f1f55

    Utilization information:
    Original: i-053f1f59 capacity: cpu=50000 mem=3840332000
    Original: i-083f1f54 capacity: cpu=50000 mem=3840332000
    Original: i-093f1f55 capacity: cpu=50000 mem=3840332000
    calculate_utilization: dummy1 utilization on i-053f1f59: cpu=40000
    calculate_utilization: dummy2:1 utilization on i-083f1f54: cpu=2000
    calculate_utilization: dummy2:2 utilization on i-093f1f55: cpu=2000
    calculate_utilization: dummy2:0 utilization on i-053f1f59: cpu=2000
    calculate_utilization: dummy2:3 utilization on i-083f1f54: cpu=2000
    calculate_utilization: dummy2:4 utilization on i-093f1f55: cpu=2000
    Remaining: i-053f1f59 capacity: cpu=8000 mem=3840332000
    Remaining: i-083f1f54 capacity: cpu=46000 mem=3840332000
    Remaining: i-093f1f55 capacity: cpu=46000 mem=3840332000

dummy1 is sharing a node with dummy2:0. The node they are on has
significantly less capacity, and is almost depleted, while the others
are largely underutilized.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.clusterlabs.org/pipermail/pacemaker/attachments/20140611/6c9494ab/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 490 bytes
Desc: OpenPGP digital signature
URL: <https://lists.clusterlabs.org/pipermail/pacemaker/attachments/20140611/6c9494ab/attachment-0004.sig>