[CASSANDRA-7438] Serializing Row cache alternative (Fully off heap)

• Type: Improvement
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 2.2.0 beta 1
• Labels: performance

Environment

Linux

• Impacts: Docs
• Assignee: Robert Stupp
• Reporter: Vijay

Authors

Robert Stupp

Reviewers

Ariel Weisberg

• Created: 24/Jun/14 07:38
• Updated: 06/Nov/19 22:05
• Resolved: 21/Jan/15 19:56

Description

Currently SerializingCache is partially off heap, keys are still stored in JVM heap as BB,

• There is a higher GC costs for a reasonably big cache.
• Some users have used the row cache efficiently in production for better results, but this requires careful tunning.
• Overhead in Memory for the cache entries are relatively high.

So the proposal for this ticket is to move the LRU cache logic completely off heap and use JNI to interact with cache. We might want to ensure that the new implementation match the existing API's (ICache), and the implementation needs to have safe memory access, low overhead in memory and less memcpy's (As much as possible).

We might also want to make this cache configurable.

Issue Links

• links to: Git branch (OHC)