RFR (S): 8155233: Lazy coarse map clear

[Thomas Schatzl]

Hi Mikael,

On Thu, 2016-04-28 at 16:20 +0200, Mikael Gerdin wrote:
> Hi Thomas,
> 
> On 2016-04-28 13:15, Thomas Schatzl wrote:
> > 
> > Hi all,
> > 
> >    can I have reviews for this tiny fix?
> > 
> > A significant part of remembered set clearing is spent on clearing
> > the
> > coarse remembered set, particularly on large heaps.
> > 
> > One way to avoid this work most of the time is to only clear the
> > coarse
> > bitmaps if they have actually been dirtied.
> > 
> > CR:
> > https://bugs.openjdk.java.net/browse/JDK-8155233
> > Webrev:
> > http://cr.openjdk.java.net/~tschatzl/8155233/webrev/
> Looks good.
> /Mikael
> 


  thanks for your review.

Thomas