hadoop-common-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Todd Lipcon (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HADOOP-7335) Force entropy to come from non-true random for tests
Date Wed, 01 Jun 2011 23:14:47 GMT

    [ https://issues.apache.org/jira/browse/HADOOP-7335?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13042504#comment-13042504
] 

Todd Lipcon commented on HADOOP-7335:
-------------------------------------

Yea, I just tried changing my environment to file:/dev/urandom and it doesn't work correctly
- I see Jetty hanging at startup. jstack shows it trying to read entropy. If I use file:///dev/urandom
as I did in this patch, it starts immediately every time.

> Force entropy to come from non-true random for tests
> ----------------------------------------------------
>
>                 Key: HADOOP-7335
>                 URL: https://issues.apache.org/jira/browse/HADOOP-7335
>             Project: Hadoop Common
>          Issue Type: Improvement
>          Components: build, test
>    Affects Versions: 0.22.0
>            Reporter: Todd Lipcon
>            Assignee: Todd Lipcon
>            Priority: Minor
>         Attachments: hadoop-7335.txt
>
>
> Passing the system property {{-Djava.security.egd=file:///dev/urandom}} forces the JVM
to seed its PRNG from non-true random (/dev/urandom) instead of the true random (/dev/random).
This makes the tests run faster, since without it they often hang waiting for entropy while
Jetty is initializing.
> We should turn this on for the test targets by default, so developers/hudson boxes don't
have to make this change system-wide or use workarounds like rngtools.

--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira

Mime
View raw message