2172   HeapRegion* dummy_region = new_heap_region(0 /* index of bottom region */,
2173                                              _g1_reserved.start());
2174   // We'll re-use the same region whether the alloc region will
2175   // require BOT updates or not and, if it doesn't, then a non-young
2176   // region will complain that it cannot support allocations without
2177   // BOT updates. So we'll tag the dummy region as young to avoid that.
2178   dummy_region->set_young();
2179   // Make sure it's full.
2180   dummy_region->set_top(dummy_region->end());
2181   G1AllocRegion::setup(this, dummy_region);
2182 
2183   init_mutator_alloc_region();
2184 
2185   // Do create of the monitoring and management support so that
2186   // values in the heap have been properly initialized.
2187   _g1mm = new G1MonitoringSupport(this);
2188 
2189   return JNI_OK;
2190 }
2191 




2192 void G1CollectedHeap::ref_processing_init() {
2193   // Reference processing in G1 currently works as follows:
2194   //
2195   // * There are two reference processor instances. One is
2196   //   used to record and process discovered references
2197   //   during concurrent marking; the other is used to
2198   //   record and process references during STW pauses
2199   //   (both full and incremental).
2200   // * Both ref processors need to 'span' the entire heap as
2201   //   the regions in the collection set may be dotted around.
2202   //
2203   // * For the concurrent marking ref processor:
2204   //   * Reference discovery is enabled at initial marking.
2205   //   * Reference discovery is disabled and the discovered
2206   //     references processed etc during remarking.
2207   //   * Reference discovery is MT (see below).
2208   //   * Reference discovery requires a barrier (see below).
2209   //   * Reference processing may or may not be MT
2210   //     (depending on the value of ParallelRefProcEnabled
2211   //     and ParallelGCThreads).

2172   HeapRegion* dummy_region = new_heap_region(0 /* index of bottom region */,
2173                                              _g1_reserved.start());
2174   // We'll re-use the same region whether the alloc region will
2175   // require BOT updates or not and, if it doesn't, then a non-young
2176   // region will complain that it cannot support allocations without
2177   // BOT updates. So we'll tag the dummy region as young to avoid that.
2178   dummy_region->set_young();
2179   // Make sure it's full.
2180   dummy_region->set_top(dummy_region->end());
2181   G1AllocRegion::setup(this, dummy_region);
2182 
2183   init_mutator_alloc_region();
2184 
2185   // Do create of the monitoring and management support so that
2186   // values in the heap have been properly initialized.
2187   _g1mm = new G1MonitoringSupport(this);
2188 
2189   return JNI_OK;
2190 }
2191 
2192 size_t G1CollectedHeap::conservative_max_heap_alignment() {
2193   return HeapRegion::max_region_size();
2194 }
2195 
2196 void G1CollectedHeap::ref_processing_init() {
2197   // Reference processing in G1 currently works as follows:
2198   //
2199   // * There are two reference processor instances. One is
2200   //   used to record and process discovered references
2201   //   during concurrent marking; the other is used to
2202   //   record and process references during STW pauses
2203   //   (both full and incremental).
2204   // * Both ref processors need to 'span' the entire heap as
2205   //   the regions in the collection set may be dotted around.
2206   //
2207   // * For the concurrent marking ref processor:
2208   //   * Reference discovery is enabled at initial marking.
2209   //   * Reference discovery is disabled and the discovered
2210   //     references processed etc during remarking.
2211   //   * Reference discovery is MT (see below).
2212   //   * Reference discovery requires a barrier (see below).
2213   //   * Reference processing may or may not be MT
2214   //     (depending on the value of ParallelRefProcEnabled
2215   //     and ParallelGCThreads).