[
https://issues.apache.org/jira/browse/CASSANDRA-10855?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15234296#comment-15234296
]
Ben Manes commented on CASSANDRA-10855:
---------------------------------------
When Cassandra moves to TPC, it should take less than a day to write a TinyLFU
cache if you borrow my [4-bit CountMin
sketch|https://github.com/ben-manes/caffeine/blob/master/caffeine/src/main/java/com/github/benmanes/caffeine/cache/FrequencySketch.java].
I might evolve that to include the doorkeeper and other tricks, but it hasn't
been a priority yet. The simulator includes a variant using incremental reset
(which would be my preference for a TPC) and shows a negligible difference in
hit rates. A Go developer read the paper and wrote an implementation for fun in
a few days, and I'm happy to review anyone's version.
Caffeine tackled the research and concurrency side, but no reason to adopt it
once TPC. Best to take ideas, leverage its simulator to fine tune, and share
insights.
> Use Caffeine (W-TinyLFU) for on-heap caches
> -------------------------------------------
>
> Key: CASSANDRA-10855
> URL: https://issues.apache.org/jira/browse/CASSANDRA-10855
> Project: Cassandra
> Issue Type: Improvement
> Reporter: Ben Manes
> Labels: performance
>
> Cassandra currently uses
> [ConcurrentLinkedHashMap|https://code.google.com/p/concurrentlinkedhashmap]
> for performance critical caches (key, counter) and Guava's cache for
> non-critical (auth, metrics, security). All of these usages have been
> replaced by [Caffeine|https://github.com/ben-manes/caffeine], written by the
> author of the previously mentioned libraries.
> The primary incentive is to switch from LRU policy to W-TinyLFU, which
> provides [near optimal|https://github.com/ben-manes/caffeine/wiki/Efficiency]
> hit rates. It performs particularly well in database and search traces, is
> scan resistant, and as adds a very small time/space overhead to LRU.
> Secondarily, Guava's caches never obtained similar
> [performance|https://github.com/ben-manes/caffeine/wiki/Benchmarks] to CLHM
> due to some optimizations not being ported over. This change results in
> faster reads and not creating garbage as a side-effect.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
