[
https://issues.apache.org/jira/browse/CASSANDRA-7486?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14049217#comment-14049217
]
Benedict commented on CASSANDRA-7486:
-------------------------------------
We need to make sure we test over an extended period with a variety of
operations being exercised against the cluster. This is probably a good
opportunity to try and define a real world burn in test as well, and what
parameters should be included.
Some things to consider:
# Range of data distributions, including (esp. for this) large partitions and
very large cells. Possibly run two or three parallel stress profiles with very
different data profiles to really give GC a headache dealing with different
velocities / lifetimes.
# Incremental and full repairs
# Hint accumulation / node death
# Tombstones / Range Tombstones
# Secondary indexes?
I'd suggest ignoring some variables, and e.g. stick with just netty, so we can
define a single complex workload and run it for an extended period and get a
good result. While our client buffers behave quite differently with each, I'm
happy tuning defaults for native now it's faster.
It might also be useful, for this test only, to see for a single node how well
the two degrade as heap pressure increases, by artificially consuming large
portions of the heap for the duration of a more simple stress test.
> Compare CMS and G1 pause times
> ------------------------------
>
> Key: CASSANDRA-7486
> URL: https://issues.apache.org/jira/browse/CASSANDRA-7486
> Project: Cassandra
> Issue Type: Test
> Components: Config
> Reporter: Jonathan Ellis
> Assignee: Ryan McGuire
> Fix For: 2.1.0
>
>
> See
> http://www.slideshare.net/MonicaBeckwith/garbage-first-garbage-collector-g1-gc-migration-to-expectations-and-advanced-tuning
> and https://twitter.com/rbranson/status/482113561431265281
> May want to default 2.1 to G1.
> 2.1 is a different animal from 2.0 after moving most of memtables off heap.
> Suspect this will help G1 even more than CMS. (NB this is off by default but
> needs to be part of the test.)
--
This message was sent by Atlassian JIRA
(v6.2#6252)
