[
https://issues.apache.org/jira/browse/CASSANDRA-9472?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14629823#comment-14629823
]
Benedict commented on CASSANDRA-9472:
-------------------------------------
This is just talking about partially off-heap as we previously had. Introducing
fully offheap memtables is a significant undertaking, and really requires a lot
of scaffolding work:
* probably our own offheap compacting arena allocator, as I once attempted to
introduce
[here|https://github.com/belliottsmith/cassandra/tree/6843-offheap.gc], or
something similar, else modifications will much more rapidly exhaust memtable
space (by retaining a lot of space that isn't actually referenced by anything
until flush happens)
* an off-heap version of, probably, CASSANDRA-7282 (the easiest data structure
to make offheap)
* an off-heap btree, or btrie if we've gotten that far
Much of this would be better introduced once we have a more advanced storage
format, and have (for instance) normalised to a byte-order comparable
serialization format for clustering data, since we won't be duplicating the
work.
> Reintroduce off heap memtables
> ------------------------------
>
> Key: CASSANDRA-9472
> URL: https://issues.apache.org/jira/browse/CASSANDRA-9472
> Project: Cassandra
> Issue Type: Improvement
> Components: Core
> Reporter: Benedict
> Fix For: 3.x
>
>
> CASSANDRA-8099 removes off heap memtables. We should reintroduce them ASAP.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
