graphite-web: Significant slowdown caused by REMOTE_STORE_MERGE_RESULTS

I recently did an update from source and found rendering graphs had significantly slowed down.

I tracked problem down to commit bc18f9730b102cd5ab3ba1409b6760471f4b43ea at this branching, since Calculate best minimal node set is no longer entered by default.

Setting REMOTE_STORE_MERGE_RESULTS = False in local_settings.py resolves the problem.

• Since, I’m not using CLUSTERS maybe REMOTE_STORE_MERGE_RESULTS should not be effective here?
• Another thought. Should REMOTE_STORE_MERGE_RESULTS be False by default? (I don’t know enough about operation with clusters to make the call.)

cc @deniszh