yifan-c commented on code in PR #4399: URL: https://github.com/apache/cassandra/pull/4399#discussion_r2414946121
########## conf/cassandra.yaml: ########## @@ -617,6 +617,54 @@ counter_cache_save_period: 7200s # Disabled by default, meaning all keys are going to be saved # counter_cache_keys_to_save: 100 +# Dictionary compression settings for ZSTD dictionary-based compression +# These settings control the automatic training and caching of compression dictionaries +# for tables that use ZSTD dictionary compression. + +# How often to refresh compression dictionaries across the cluster. +# During refresh, nodes will check for newer dictionary versions and update their caches. +# Min unit: s +compression_dictionary_refresh_interval: 3600s + +# Initial delay before starting the first dictionary refresh cycle after node startup. +# This prevents all nodes from refreshing simultaneously when the cluster starts. Review Comment: I do not think starting all nodes at the same moment is a requirement. The refresh interval just defines how frequent each node should check the system table. When there is a new dictionary trained, the node will broadcast the message to all live nodes to notify the dictionary is available. This happens outside of the periodic polling. Combining both, you can consider the interval as the upper bound of how dictionary is refreshed (when broadcasting fails at some nodes). When some nodes are running with the prior dictionary or no dictionary, it is still not a huge issue, from the perspective of read and write SSTables. Eventually, all nodes will pick up the latest. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
