RFR (M) 8213753: Move timing of ProtectionDomainTable and ResolvedMethodTable cleanup to service thread

[Gerard Ziemski]

hi Coleen,

Looks good and I’m glad to see "set_item_clean_count/mark_item_clean_count" stuff go away.

#1 In src/hotspot/share/classfile/symbolTable.cpp we no longer need the comment, so should remove it:

 472   if (clean_hint) {
 473     // we just found out that there is a dead item,
 474     // which we were unable to clean right now,
 475     // but we have no way of telling whether it's
 476     // been previously counted or not, so mark
 477     // it only if no other items were found yet
 478     mark_has_items_to_clean();
 479     check_concurrent_work();
 480   }

and just have:

 472   if (clean_hint) {
 473     mark_has_items_to_clean();
 474     check_concurrent_work();
 475   }

#2 For a followup, I think we can do some further simplifications:

a) Combine "mark_has_items_to_clean() and check_concurrent_work()” into one
b) Possibly eliminate the 3 new APIs: “reset_has_items_to_clean/mark_has_items_to_clean/has_items_to_clean”

But the main task of changing how we trigger the table cleanup looks fine.


cheers
 

> On Jan 28, 2019, at 4:09 PM, coleen.phillimore at oracle.com wrote:
> 
> Summary: remove gc timing for short runtime cleanup triggering; make symbol table cleaning triggered automatically on unloading
> 
> Ran runThese with all Oracle GCs and got similar numbers of symbols unloaded.  Also ran tier1-5.
> 
> open webrev at http://cr.openjdk.java.net/~coleenp/2019/8213753.01/webrev
> bug link https://bugs.openjdk.java.net/browse/JDK-8213753
> 
> Thanks,
> Coleen