[CASSANDRA-6508] counters++ coalesce counter mutations with the same partition key

• Type: Improvement
• Status: Resolved
• Priority: Normal
• Resolution: Duplicate
• Assignee: Aleksey Yeschenko
• Reporter: Aleksey Yeschenko

Authors

Aleksey Yeschenko

• Created: 19/Dec/13 02:12
• Updated: 16/Apr/19 09:31
• Resolved: 18/Mar/14 21:17

Description

CASSANDRA-6504 counter caching helps with hot counter cells, but doesn't really help when we have a hot counter partition and different cells within being updated simultaneously by different clients (the striped locks are partition-level, not cell-level).

To improve performance in this scenario, we could coalesce the mutations in COUNTER_MUTATION stage if they share the same partition key + target cf, and apply them together, sharing a single lock.

If beneficial, this can go into 2.1.x or 3.0, doesn't have to be 2.1.0.

Issue Links

• duplicates: CASSANDRA-6880 counters++ lock on cells, not partitions
• is related to: CASSANDRA-6504 counters++