cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Robert Stupp (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (CASSANDRA-10581) Update cassandra.yaml comments to reflect memory_allocator deprecation, remove in 3.0
Date Wed, 28 Oct 2015 19:02:27 GMT

    [ https://issues.apache.org/jira/browse/CASSANDRA-10581?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14979027#comment-14979027
] 

Robert Stupp commented on CASSANDRA-10581:
------------------------------------------

Yes, it's difficult to include a check whether jemalloc is actually used. The startup code
in {{cassandra-env.sh}} preloads the library, which effectively "links" jemalloc between the
java runtime and OS {{malloc}}/{{free}} - i.e. it's basically "invisible" whether jemalloc
is used or not.

I've pushed commits for 2.2 + 3.0 with some logging to {{cassandra-env.sh}} where preloading
happens. Is this what you think of?

> Update cassandra.yaml comments to reflect memory_allocator deprecation, remove in 3.0
> -------------------------------------------------------------------------------------
>
>                 Key: CASSANDRA-10581
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-10581
>             Project: Cassandra
>          Issue Type: Bug
>            Reporter: Jim Witschey
>            Assignee: Robert Stupp
>             Fix For: 2.2.x, 3.0.0
>
>
> Looks like in 2.2+ changing the {{memory_allocator}} field in cassandra.yaml has no effect:
> https://github.com/apache/cassandra/commit/0d2ec11c7e0abfb84d872289af6d3ac386cf381f#diff-b66584c9ce7b64019b5db5a531deeda1R207
> The instructions in comments on how to use jemalloc haven't been updated to reflect this
change. [~snazy], is that an accurate assessment?
> [~iamaleksey] How do we want to handle the deprecation more generally? Warn on 2.2, remove
in 3.0?
> EDIT: I described this in a way that isn't very clear to those unfamiliar with Robert's
change. To be clear: You can still use JEMAlloc with Cassandra. The {{memory_allocator}} option
was deprecated in favor of automatically detecting if JEMAlloc is installed, and, if so, using
it. 



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message