[ovirt-users] oVirt 3.5 test day - OptaPlanner integration

[Lior Vernia]

In this test day I was to test the SLA team's OptaPlanner integration.

Some background for those who aren't familiar with the feature: the
problem of finding an optimal solution for VM scheduling/balancing is
NP-hard, therefore for large deployment it is only feasible to find
approximately optimal solutions.

OptaPlanner is a very nice utility that contains a lot of approximation
algorithms for computationally-hard problems such as scheduling, so the
plan is for oVirt to use OptaPlanner (running on a dedicated machine) to
"hint" to the administrator where to migrate VMs to achieve more optimal
placement on hosts; "optimality" is with respect to cluster policy.

Unfortunately, due to some technical difficulties and a lack of
documentation, I did not manage to get very far - only verified that
when the OptaPlanner machine and oVirt engine are properly configured,
the new tab under cluster appears and shows output from the OptaPlanner.

The feature page mainly documented the implementation of the feature,
but contained no information on what had to be installed or any example
testing scenarios. However, msivak (feature owner) was very responsive
and updated the feature page as soon as these gaps were discovered, so
now it's clear how to configure a deployment to use OptaPlanner.

Hopefully I'll be able to further test the feature soon, and at the very
latest during the next test day.

Yours, Lior.