src/share/vm/gc_implementation/g1/heapRegionManager.inline.hpp

Fri, 10 Oct 2014 15:51:58 +0200

author
tschatzl
date
Fri, 10 Oct 2014 15:51:58 +0200
changeset 7257
e7d0505c8a30
parent 7091
a8ea2f110d87
child 7535
7ae4e26cb1e0
child 9327
f96fcd9e1e1b
permissions
-rw-r--r--

8059758: Footprint regressions with JDK-8038423
Summary: Changes in JDK-8038423 always initialize (zero out) virtual memory used for auxiliary data structures. This causes a footprint regression for G1 in startup benchmarks. This is because they do not touch that memory at all, so the operating system does not actually commit these pages. The fix is to, if the initialization value of the data structures matches the default value of just committed memory (=0), do not do anything.
Reviewed-by: jwilhelm, brutisso

     1 /*
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     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
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     9  * This code is distributed in the hope that it will be useful, but WITHOUT
    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    12  * version 2 for more details (a copy is included in the LICENSE file that
    13  * accompanied this code).
    14  *
    15  * You should have received a copy of the GNU General Public License version
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    18  *
    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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    25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONMANAGER_INLINE_HPP
    26 #define SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONMANAGER_INLINE_HPP
    28 #include "gc_implementation/g1/heapRegion.hpp"
    29 #include "gc_implementation/g1/heapRegionManager.hpp"
    30 #include "gc_implementation/g1/heapRegionSet.inline.hpp"
    32 inline HeapRegion* HeapRegionManager::addr_to_region(HeapWord* addr) const {
    33   assert(addr < heap_end(),
    34         err_msg("addr: "PTR_FORMAT" end: "PTR_FORMAT, p2i(addr), p2i(heap_end())));
    35   assert(addr >= heap_bottom(),
    36         err_msg("addr: "PTR_FORMAT" bottom: "PTR_FORMAT, p2i(addr), p2i(heap_bottom())));
    38   HeapRegion* hr = _regions.get_by_address(addr);
    39   return hr;
    40 }
    42 inline HeapRegion* HeapRegionManager::at(uint index) const {
    43   assert(is_available(index), "pre-condition");
    44   HeapRegion* hr = _regions.get_by_index(index);
    45   assert(hr != NULL, "sanity");
    46   assert(hr->hrm_index() == index, "sanity");
    47   return hr;
    48 }
    50 inline void HeapRegionManager::insert_into_free_list(HeapRegion* hr) {
    51   _free_list.add_ordered(hr);
    52 }
    54 inline void HeapRegionManager::allocate_free_regions_starting_at(uint first, uint num_regions) {
    55   _free_list.remove_starting_at(at(first), num_regions);
    56 }
    58 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONMANAGER_INLINE_HPP

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