Experimental flags

Some configuration flags are marked 'unsafe' and 'experimental'. Such flags are disabled by default. You can access these flags by enabling the additional flags, --unlock_unsafe_flags and --unlock_experimental_flags.

Note that these flags might be removed or modified without a deprecation period or any prior notice in future Kudu releases. Cloudera does not support using unsafe and experimental flags. As a rule of thumb, Cloudera will not support any configuration flags not explicitly documented in the Kudu Configuration Reference Guide.

Some particularly impactful unsafe Kudu configuration options are:

--use-hybrid-clock
Setting this flag to false is highly discouraged in any production-grade deployment, as it can introduce extensive latency and behavior such as not operating in COMMIT_WAIT consistency mode, failing to handle scan operations in READ_AT_SNAPSHOT and READ_YOUR_WRITES modes, and so on.
--allow_world_readable_credentials
Do not set this flag to true, but rather set the ownership and file access mask properly using chown and chmod commands.
--allow_unsafe_replication_factor
Do not set this flag to true since even replication factors of (2 * N) is not any better than (2 * N - 1) because Kudu uses Raft consensus protocol.
--max_cell_size_bytes
If you need to increase it, you must consult with Cloudera to evaluate possible performance degradation and other issues depending on specific workload.
--max_num_columns
If you need to adjust it, you must consult with Cloudera to evaluate possible performance degradation and other issues depending on specific workload.
--rpc_num_service_threads
You should never set it higher than the number of CPU cores at a node.