separate ParallelGCThreads ?

Srinivas Ramakrishna ysr1729 at
Mon Feb 6 19:01:33 UTC 2012

Hi all --

I am wondering if there may be any traction to using a different
"ParallelGCThreads" setting for old and young
phases of Parallel GC, somewhat analogous (although i understand the
analogy is too loose) to how there are separate
numbers of  (max) parallel threads for concurrent and stop-world phases of
CMS and G1. It's of course
almost trivial to implement as of now, but it introduces yet more
(user-settable) options, multiplying existing
confusion of the roles of many of these options.

In some sense, Jon's recent infrastructure work on eventually enabling the
jvm/gc to dynamically flex the # of GC threads
works in that direction in a more pleasant and ergonomic fashion, but I was
wondering whether, in the interim, we can have
a stop-gap where the users can explicitly set the values for (for example)
old and new collections via different parameters. I am
myself somewhat conflicted by this suggestion since it starts us down a
somewhat slippery slope of
that leads to an explosion of options, but at the same time, I'd like to
hear any thoughts, comments or
opinions on this suggestion.

-- ramki
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the hotspot-gc-dev mailing list