diff -r e36165b16dde -r bd6094906ef8 hotspot/src/share/vm/runtime/virtualspace.cpp --- a/hotspot/src/share/vm/runtime/virtualspace.cpp Thu Apr 02 16:42:24 2015 -0400 +++ b/hotspot/src/share/vm/runtime/virtualspace.cpp Tue Apr 07 10:53:51 2015 +0200 @@ -37,13 +37,21 @@ _alignment(0), _special(false), _executable(false) { } -ReservedSpace::ReservedSpace(size_t size) { +ReservedSpace::ReservedSpace(size_t size, bool prefer_large_pages) { // Want to use large pages where possible and pad with small pages. size_t page_size = os::page_size_for_region_unaligned(size, 1); bool large_pages = page_size != (size_t)os::vm_page_size(); - // Don't force the alignment to be large page aligned, - // since that will waste memory. - size_t alignment = os::vm_allocation_granularity(); + size_t alignment; + if (large_pages && prefer_large_pages) { + alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity()); + // ReservedSpace initialization requires size to be aligned to the given + // alignment. Align the size up. + size = align_size_up(size, alignment); + } else { + // Don't force the alignment to be large page aligned, + // since that will waste memory. + alignment = os::vm_allocation_granularity(); + } initialize(size, alignment, large_pages, NULL, false); }