diff options
Diffstat (limited to 'nova')
| -rw-r--r-- | nova/scheduler/least_cost.py | 35 |
1 files changed, 8 insertions, 27 deletions
diff --git a/nova/scheduler/least_cost.py b/nova/scheduler/least_cost.py index 70dc180e8..f10e2c4b4 100644 --- a/nova/scheduler/least_cost.py +++ b/nova/scheduler/least_cost.py @@ -97,30 +97,11 @@ def weighted_sum(weighted_fns, host_states, weighing_properties): candidate. """ - # Make a grid of functions results. - # One row per host. One column per function. - scores = [] - for weight, fn in weighted_fns: - scores.append([fn(host_state, weighing_properties) - for host_state in host_states]) - - # Adjust the weights in the grid by the functions weight adjustment - # and sum them up to get a final list of weights. - adjusted_scores = [] - for (weight, fn), row in zip(weighted_fns, scores): - adjusted_scores.append([weight * score for score in row]) - - # Now, sum down the columns to get the final score. Column per host. - final_scores = [0.0] * len(host_states) - for row in adjusted_scores: - for idx, col in enumerate(row): - final_scores[idx] += col - - # Super-impose the host_state into the scores so - # we don't lose it when we sort. - final_scores = [(final_scores[idx], host_state) - for idx, host_state in enumerate(host_states)] - - final_scores = sorted(final_scores) - weight, host_state = final_scores[0] # Lowest score is the winner! - return WeightedHost(weight, host_state=host_state) + min_score, best_host = None, None + for host_state in host_states: + score = sum(weight * fn(host_state, weighing_properties) + for weight, fn in weighted_fns) + if min_score is None or score < min_score: + min_score, best_host = score, host_state + + return WeightedHost(min_score, host_state=best_host) |