Troubles with Shenandoah

[Simone Bordet]

Hi,

On Mon, Apr 8, 2019 at 11:13 AM Roman Kennke <rkennke at redhat.com> wrote:
>
> I'm still failing to reproduce the problem. I am running with those
> settings:
>
>           <executable>/home/rkennke/progs/jdk-
> 12+33/bin/java</executable>
>           <arguments>
>             <argument>-showversion</argument>
>             <argument>-Xmx16g</argument>
>             <argument>-Xms2g</argument>
>             <argument>-Xlog:gc:stderr:time,level,tags</argument>
>             <argument>-XX:+PrintCommandLineFlags</argument>
>             <argument>-XX:+UnlockExperimentalVMOptions</argument>
>             <argument>-XX:+UseShenandoahGC</argument>
>
>
> and I don't get lost messages or anything like that.
>
> I am having troubles with the benchmark though: if I understand it
> correctly, the server and client are asking some parameters on startup.
> However, for some reason, I don't see the messages printed out, but
> apparently it is waiting for input. So I keep pressing ENTER a couple
> of times, blindly.

Please see my previous message about this: it's a Maven library bug
and I explain the workaround.

For short runs such as ~10s when you press all enters to the
benchmark, I also don't see any problem.
They start to appear for longer runs.
Try to set batch size = 10000 (i.e. 10 times the default). This will
make the benchmark run for ~100s and for me this was enough to get the
failures.

> The questions start appearing then. (Missing
> terminal flushes/syncs?) Also, the client appears to be waiting for
> something between test runs. Is there a way to automate this? I.e. pass
> the parameters to the pom.xml and make the client not wait between
> runs?

You can't make automatic back to back runs, but you can tune the
parameters to make a run longer, see above.

-- 
Simone Bordet
---
Finally, no matter how good the architecture and design are,
to deliver bug-free software with optimal performance and reliability,
the implementation technique must be flawless.   Victoria Livschitz