trove-specs/specs/liberty/cassandra-configuration-groups.rst

Cassandra Configuration Groups

Launchpad blueprint:

https://blueprints.launchpad.net/trove/+spec/cassandra-configuration-groups

Problem Description

The Cassandra datastore currently does not support configuration groups.

Proposed Change

The patch set will implement configuration groups for Cassandra 2.1.

Configuration

The configuration template will be updated to the default template for the target platform.

• templates/cassandra/config.template

Database

None

Public API

None

Public API Security

None

Python API

None (empty section added after merging)

CLI (python-troveclient)

None (empty section added after merging)

Internal API

None

Guest Agent

Cassandra stores its configuration in 'cassandra.yaml' file (commonly in '/etc/cassandra'). The node (datastore service) has to be restarted for any changes to the configuration file to take effect. All configuration changes will therefore be requiring database restart and 'apply_overrides' will be implemented as no-op.

Overrides will be implemented by replacing the current file with an updated one. The old file will be backed up in the same directory (as *.old) and restored on configuration reset.

Most configuration properties will be available via configuration groups. Some, however, do not make sense in the Trove context.

These include:

• irrelevant options (like automatic snapshots, since the Trove user cannot retrieve them)
• guestagent specific (e.g. file paths, passwords)
• items that Trove needs to control (replication/clustering properties)

See Available Configuration Properties for the full list of supported options.

The user should be able to specify configurations properties as standard Python YAML objects - key-value pairs and dicts.

Available Configuration Properties

Properties not included in the lists are kept at their default values and are not configurable via Trove.

The properties configurable by the user via the Trove API:

• cluster_name
• listen_address
• commit_failure_policy
• disk_failure_policy
• endpoint_snitch
• seed_provider
• compaction_throughput_mb_per_sec
• memtable_total_space_in_mb
• concurrent_reads
• concurrent_writes
• phi_convict_threshold
• commitlog_sync
• commitlog_segment_size_in_mb
• commitlog_total_space_in_mb
• compaction_preheat_key_cache
• concurrent_compactors
• in_memory_compaction_limit_in_mb
• preheat_kernel_page_cache
• sstable_preemptive_open_interval_in_mb
• memtable_allocation_type
• memtable_cleanup_threshold
• file_cache_size_in_mb
• memtable_flush_queue_size
• memtable_flush_writers
• memtable_heap_space_in_mb
• memtable_offheap_space_in_mb
• column_index_size_in_kb
• index_summary_capacity_in_mb
• index_summary_resize_interval_in_minutes
• reduce_cache_capacity_to
• reduce_cache_sizes_at
• stream_throughput_outbound_megabits_per_sec
• inter_dc_stream_throughput_outbound_megabits_per_sec
• trickle_fsync
• trickle_fsync_interval_in_kb
• auto_bootstrap
• batch_size_warn_threshold_in_kb
• broadcast_address
• initial_token
• initial_token
• num_tokens
• partitioner
• key_cache_keys_to_save
• key_cache_save_period
• key_cache_size_in_mb
• row_cache_keys_to_save
• row_cache_size_in_mb
• row_cache_save_period
• memory_allocator
• counter_cache_size_in_mb
• counter_cache_save_period
• counter_cache_keys_to_save
• counter_cache_keys_to_save
• tombstone_warn_threshold
• tombstone_failure_threshold
• range_request_timeout_in_ms
• read_request_timeout_in_ms
• counter_write_request_timeout_in_ms
• cas_contention_timeout_in_ms
• truncate_request_timeout_in_ms
• write_request_timeout_in_ms
• request_timeout_in_ms
• cross_node_timeout
• internode_send_buff_size_in_bytes
• internode_recv_buff_size_in_bytes
• internode_compression
• inter_dc_tcp_nodelay
• streaming_socket_timeout_in_ms
• native_transport_max_threads
• native_transport_max_frame_size_in_mb
• broadcast_rpc_address
• rpc_keepalive
• rpc_max_threads
• rpc_min_threads
• rpc_recv_buff_size_in_bytes
• rpc_send_buff_size_in_bytes
• rpc_server_type
• dynamic_snitch_badness_threshold
• dynamic_snitch_reset_interval_in_ms
• dynamic_snitch_update_interval_in_ms
• hinted_handoff_enabled
• hinted_handoff_throttle_in_kb
• max_hint_window_in_ms
• max_hints_delivery_threads
• batchlog_replay_throttle_in_kb
• request_scheduler
• request_scheduler_id
• request_scheduler_options
• thrift_framed_transport_size_in_mb
• thrift_max_message_length_in_mb
• permissions_validity_in_ms
• permissions_update_interval_in_ms

Non-configurable properties with updated default values:

• authenticator: org.apache.cassandra.auth.PasswordAuthenticator
• authorizer: org.apache.cassandra.auth.CassandraAuthorizer
• snapshot_before_compaction: false
• auto_snapshot: false
• rpc_address: (controlled-by guestagent)
• broadcast_rpc_address: (controlled-by guestagent)
• listen_address: (controlled-by guestagent)
• seed_provider.parameters.seeds: (controlled-by guestagent)

Alternatives

None

Implementation

Assignee(s)

Petr Malik <pmalik@tesora.com>

Milestones

Liberty

Work Items

1. Implement functionality to handle (read/write/update) YAML files.
2. Implement configuration-related manager API calls.

Upgrade Implications

None

Dependencies

The patch set will be building on functionality implemented in blueprint: cassandra-database-user-functions

Testing

Unittests will be added to validate implemented functions and non-trivial codepaths.

Documentation Impact

The datastore documentation should be updated to reflect the enabled features.

References

Documentation on Cassandra 2.1: http://docs.datastax.com/en/cassandra/2.1/cassandra/gettingStartedCassandraIntro.html Documentation on Cassandra 2.1 configuration properties: http://docs.datastax.com/en/cassandra/2.1/cassandra/configuration/configTOC.html