Review request: 8015486: PSScavenge::is_obj_in_young is unnecessarily slow with UseCompressedOops
jon.masamitsu at oracle.com
Thu May 30 19:38:01 UTC 2013
Very nice change. Looks good.
On 5/30/13 2:14 AM, Stefan Karlsson wrote:
> 8015486: PSScavenge::is_obj_in_young is unnecessarily slow with
> Summary: Compare compressed oops to a compressed young gen boundary
> instead of uncompressing the oops before doing the young gen boundary
> Instead of decompressing every single oop before checking against the
> young gen boundary, we could store a compressed young gen boundary and
> compare the compressed oops against that value. This will save both a
> null-check and the decompression code for all the visited oops.
> This give about 3% lower young GC times when running SPECjbb2005.
More information about the hotspot-gc-dev