There’s a manual way to force a flush or compaction for a table using the yb-admin
tool.
% yb-admin -master_addresses <ip1>:7100,<ip2>:7100,<ip3>:7100 compact_table <keyspace> <tablename>
% yb-admin -master_addresses <ip1>:7100,<ip2>:7100,<ip3>:7100 flush_table <keyspace> <tablename>