[CASSANDRA-2449] Deprecate or modify per-cf memtable sizes in favor of the global threshold

• Type: Improvement
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 1.0.0
• Assignee: Jonathan Ellis
• Reporter: Stu Hood

Authors

Jonathan Ellis

Reviewers

Brandon Williams

• Created: 11/Apr/11 19:08
• Updated: 16/Apr/19 09:33
• Resolved: 08/Sep/11 03:37

Description

The new memtable_total_space_in_mb setting is an excellent way to cap memory usage for memtables, and one could argue that it should replace the per-cf memtable sizes entirely. On the other hand, people may still want a knob to tune to flush certain cfs less frequently.

I think a best of both worlds approach might be to deprecate the memtable_(throughput|operations) settings, and replace them with a preference value, which controls the relative memory usage of one CF versus another (all CFs at 1 would mean equal preference). For backwards compatibility, we could continue to read from the _throughput value and treat it as the preference value, while logging a warning.

Issue Links

• relates to: CASSANDRA-2006 Serverwide caps on memtable thresholds