expired sstables are skipped in the compaction setup phase, because they don't
need to be actually compacted, but rather only deleted at the end.
that is causing such sstables to not be removed from the backlog tracker,
meaning that backlog caused by expired sstables will not be removed even after
their deletion, which means shares will be higher than needed, making compaction
potentially more aggressive than it have to.
to fix this bug, let's manually register these sstables into the monitor,
such that they'll be removed from the tracker once compaction completes.
Fixes#6054.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <20210216203700.189362-1-raphaelsc@scylladb.com>
5206a97915