loss of cause??

[Mikael Gerdin]

Richard,

On 10/10/2013 04:22 PM, Richard Warburton wrote:
> Hi,
>
>     If you want the GC causes for all gcs in 7u40 please use
>     -XX:+PrintGCCause
>
>
> Can you explain what the motivation is for this change in behaviour?  I
> ask because the continued instability of GC Log format isn't helpful to
> end users and removing useful performance information is effectively a
> regression in available functionality.

The code change was discussed a while back:
http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2012-May/004461.html

We chose to not add the GC cause to all gc log records since we felt 
that was too large a change for 7.
The previous behavior was completely inconsistent, all the different 
GC:s had different ways of signaling that a full gc was caused by a 
Systm.gc() call and System.gc() was the only gc cause which was logged.

In 8 we decided to enable gc cause printing for all gc log records.

/Mikael

>
> regards,
>
>    Dr. Richard Warburton
>
> http://insightfullogic.com
> @RichardWarburto <http://twitter.com/richardwarburto>