Remapping phase

Simone Bordet simone.bordet at
Tue Oct 22 09:00:13 UTC 2019


On Tue, Oct 22, 2019 at 10:46 AM Per Liden <per.liden at> wrote:
> I'm curious, since you're asking, do you have a real world workload
> where you suspect letting the GC immediately remap the entire graph
> would actually pay off?

No, I was curious as just after a relocation possibly all the mutators
will trigger the load barrier, multiple times to access the objects
they need to work with, so they will incur in overhead but they have
all CPUs available.
Since the remapping would start from the roots, i.e. local variables,
that are likely to be used first by the mutator, then the mutators
would have less overhead because they won't trigger the load barrier
as much, but have less CPUs available.

I have also other sources confirming that doing an early remapping is
not worth it.


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

More information about the zgc-dev mailing list