compaction_manager: Increase cleanup compaction resilience when low on disk space
compaction_manager: Increase cleanup compaction resilience when low on disk space

In a scenario where node is running out of disk space, which is a common
cause of cluster expansion, it's very important to clean up the smallest
files first to increase the chances of success when the biggest files are
reached down the road. That's possible given that cleanup operates on a
single file at a time, and that the smaller the file the smaller the
space requirement.

Signed-off-by: Raphael S. Carvalho <1e2942cea40e3b4d2162dfcd9e53e41c05a84d22@scylladb.com>
Message-Id: <20210303165520.55563-1-1e2942cea40e3b4d2162dfcd9e53e41c05a84d22@scylladb.com>

scylladb/scylla,scylladb/scylla,scylladb/scylla,scylladb/scylla