[CASSANDRA-14573] Expose settings in virtual table

• Type: New Feature
• Status: Resolved
• Priority: Low
• Resolution: Fixed
• Fix Version/s: 4.0-alpha1, 4.0
• Labels: pull-request-available virtual-tables
• Assignee: Chris Lohfink
• Reporter: Chris Lohfink

Authors

Chris Lohfink

Reviewers

Aleksey Yeschenko

• Created: 17/Jul/18 17:26
• Updated: 15/May/20 08:04
• Resolved: 21/Aug/18 15:10

Description

Allow both viewing what the settings are (currently impossible for some) and allow changing some settings.

Example:

UPDATE system_info.settings SET value = 'false' WHERE setting = 'hinted_handoff_enabled';

SELECT * FROM system_info.settings WHERE writable = True;

 setting                                              | value      | writable
------------------------------------------------------+------------+----------
                      batch_size_fail_threshold_in_kb |         50 |     True
                      batch_size_warn_threshold_in_kb |          5 |     True
                         cas_contention_timeout_in_ms |       1000 |     True
                     compaction_throughput_mb_per_sec |         16 |     True
                                concurrent_compactors |          2 |     True
                               concurrent_validations | 2147483647 |     True
                  counter_write_request_timeout_in_ms |       5000 |     True
                               hinted_handoff_enabled |      false |     True
                        hinted_handoff_throttle_in_kb |       1024 |     True
                                  incremental_backups |      false |     True
 inter_dc_stream_throughput_outbound_megabits_per_sec |        200 |     True
                                phi_convict_threshold |        8.0 |     True
                          range_request_timeout_in_ms |      10000 |     True
                           read_request_timeout_in_ms |       5000 |     True
                                request_timeout_in_ms |      10000 |     True
          stream_throughput_outbound_megabits_per_sec |        200 |     True
                          tombstone_failure_threshold |     100000 |     True
                             tombstone_warn_threshold |       1000 |     True
                       truncate_request_timeout_in_ms |      60000 |     True
                          write_request_timeout_in_ms |       2000 |     True

Issue Links

• supercedes: CASSANDRA-9233 Allow system variables to be retrieved and set via CQL
• links to: GitHub Pull Request #242
• links to: GitHub Pull Request #242