RFR: JDK-8131784 : Add tracing info to LowMemoryTest.java to help 8130339 diagnosis

[Jaroslav Bachorik]

Hi Olivier,

On 30.7.2015 18:55, olivier.lagneau at oracle.com wrote:
> Hi,
>
> Could you please review this fix:
> bug: https://bugs.openjdk.java.net/browse/JDK-8131784
> webrev: http://cr.openjdk.java.net/~olagneau/8131784/webrev.00/
>
> We add tracing information to help diagnosing master bug problem
> (https://bugs.openjdk.java.net/browse/JDK-8130339),
> and we will monitor the quarantined runs to check for any failure and
> get more diagnosis info.
>
> Since the test already provides some information which is not collected
> when it fails with timeout,
> the idea is to collect subprocess I/O (stdout, stderr) by using
> ProcessTools.startProcess rather
> that OutputAnalyzer.executeProcess. The subprocess I/Os will be
> collected while it's running
> rather than waiting the subprocess termination.
>
> A few additional infos have also been added to get more information.
>
> Note that this "tracing" change should be temporary and will be removed
> when a fix for 8130339 has been found.

Instead of `ProcessTools.startProcess(prefixName, pb, (l) -> {return 
true;} );` at line 132 you can do `ProcessTools.startProcess(prefixName, 
pb, null);`. It will have the same effect.

Why is that 2 seconds sleep necessary at line 135?

L373 and L384 - better use 'SweeperThread' instead of 'SweepThread' to 
correspond to the class name.

-JB-

>
> Thanks,
> Olivier.
>