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[Jonathan Proulx <jon@xxxxxxxxxxxxx>]

Hi All,

Looking for a sanity test before I file a bug.  I very recently
upgraded my install to Folsom (on top of Ubuntu 12.04/kvm).  My
scheduler settings in nova.conf are:

scheduler_available_filters=nova.scheduler.filters.standard_filters
scheduler_default_filters=AvailabilityZoneFilter,RamFilter,CoreFilter,ComputeFilter
least_cost_functions=nova.scheduler.least_cost.compute_fill_first_cost_fn
compute_fill_first_cost_fn_weight=1.0
cpu_allocation_ratio=1.0

This had been working to fill systems based on available RAM and to
not exceed 1:1 allocation ration of CPU resources with Essex.  With
Folsom, if I specify a moderately large number of instances to boot or
spin up single instances in a tight shell loop they will all get
schedule on the same compute node well in excess of the number of
available vCPUs . If I start them one at a time (using --poll in a
shell loop so each instance is started before the next launches) then
I get the expected allocation behaviour.

I see https://bugs.launchpad.net/nova/+bug/1011852 which seems to
attempt to address this issue but as I read it that "fix" is based on
retrying failures.  Since KVM is capable of over committing both CPU
and Memory I don't seem to get retryable failure, just really bad
performance.

Am I missing something this this fix or perhaps there's a reported bug
I didn't find in my search, or is this really a bug no one has
reported?

Thanks,
-Jon