RFR (M) 8139551: Scalability problem with redefinition - multiple code cache walks

[dean.long at oracle.com]

Could you move this code:

      // Mark dependent AOT nmethods, which are only found via the class 
redefined.
      AOTLoader::mark_evol_dependent_methods(ik);

into this function:

      CodeCache::mark_for_evol_deoptimization(ik)

The rest looks good.

dl

On 2/4/19 7:08 AM, coleen.phillimore at oracle.com wrote:
> Summary: Walk code cache and deoptimize once per redefinition.*
>
> *This change touches the AOT and code cache code.  I tried to describe 
> it in the comments in the RFE.  Basically, for redefinition, we walk 
> the code cache per class redefined in order to find evol_method 
> dependencies, then deoptimize if we find them, and then walk the code 
> cache again to mark the deoptimized nmethods as not_entrant.
>
> I replaced this with only marking any nmethods for the class's methods 
> to deoptimize (following InstanceKlass::_methods), also marking aot 
> methods dependent on the class, and then doing the code cache walk to 
> follow the evol_method dependencies at the end of redefinition for all 
> the classes.   The new code uses the Method::is_old() flag rather than 
> comparing each method in the InstanceKlass.  Then deoptimization and 
> marking not_entrant is done once at the end of the redefinition as well.
>
> Tested with tier1-6, all the redefinition tests locally:
>
> make test TEST=open/test/hotspot/jtreg/vmTestbase/nsk/jvmti >&jvmti.out
> make test TEST=open/test/hotspot/jtreg/vmTestbase/nsk/jdi >&jdi.out
> make test TEST=open/test/hotspot/jtreg/runtime/RedefineTests 
> >&redefine.out
> make test TEST=open/test/jdk/java/lang/instrument >&instrument.out
>
> new test, and JMH test (see CR for results).
>
> Thanks,
> Coleen
>
>