Hi, Happy New Year!
I would like to discuss the following idea: Open-source Cassandra (CASSANDRA-15013 <https://issues.apache.org/jira/browse/CASSANDRA-15013>) has an elementary built-in memory rate limiter based on the incoming payload from user requests. This rate limiter activates if any incoming user request’s payload exceeds certain thresholds. However, the existing rate limiter only solves limited-scope issues. Cassandra's server-side meltdown due to overload is a known problem. Often we see that a couple of busy nodes take down the entire Cassandra ring due to the ripple effect. The following document proposes a generic purpose comprehensive rate limiter that works considering system signals, such as CPU, and internal signals, such as thread pools. The rate limiter will have knobs to filter out internal traffic, system traffic, replication traffic, and furthermore based on the types of queries. More design details to this doc: [OSS] Cassandra Generic Purpose Rate Limiter - Google Docs <https://docs.google.com/document/d/1w-A3fnoeBS6tS1ffBda_R0QR90olzFoMqLE7znFEUrQ/edit> Please let me know your thoughts. Jaydeep
