"
Tests: unit (release)
Before merging the LCS controller, we merged patches that would
guarantee that LCS would move towards zero backlog - otherwise the
backlog could get too high.
We didn't do the same for STCS, our first controlled strategy. So we may
end up with a situation where there are many SSTables inducing a large
backlog, but they are not yet meeting the minimum criteria for
compaction. The backlog, then, never goes down.
This patch changes the SSTable selection criteria so that if there is
nothing to do, we'll keep pushing towards reaching a state of zero
backlog. Very similar to what we did for LCS.
"
* 'stcs-min-threshold-v4' of github.com:glommer/scylla:
STCS: bypass min_threshold unless configure to enforce strictly
compaction_strategy: allow the user to tell us if min_threshold has to be strict
(cherry picked from commit f0fc888381)
9df3df92bc