< prev index next >

src/hotspot/share/gc/shenandoah/shenandoahArguments.cpp

Print this page

  7  * under the terms of the GNU General Public License version 2 only, as
  8  * published by the Free Software Foundation.
  9  *
 10  * This code is distributed in the hope that it will be useful, but WITHOUT
 11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 13  * version 2 for more details (a copy is included in the LICENSE file that
 14  * accompanied this code).
 15  *
 16  * You should have received a copy of the GNU General Public License version
 17  * 2 along with this work; if not, write to the Free Software Foundation,
 18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 19  *
 20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 21  * or visit www.oracle.com if you need additional information or have any
 22  * questions.
 23  *
 24  */
 25 
 26 #include "precompiled.hpp"
 27 #include "gc/shared/fullGCForwarding.hpp"
 28 #include "gc/shared/gcArguments.hpp"
 29 #include "gc/shared/tlab_globals.hpp"
 30 #include "gc/shared/workerPolicy.hpp"
 31 #include "gc/shenandoah/shenandoahArguments.hpp"
 32 #include "gc/shenandoah/shenandoahCollectorPolicy.hpp"
 33 #include "gc/shenandoah/shenandoahGenerationalHeap.hpp"
 34 #include "gc/shenandoah/shenandoahHeap.inline.hpp"
 35 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
 36 #include "runtime/globals_extension.hpp"
 37 #include "runtime/java.hpp"
 38 #include "utilities/defaultStream.hpp"
 39 
 40 void ShenandoahArguments::initialize() {
 41 #if !(defined AARCH64 || defined AMD64 || defined IA32 || defined PPC64 || defined RISCV64)
 42   vm_exit_during_initialization("Shenandoah GC is not supported on this platform.");
 43 #endif
 44 
 45 #if 0 // leave this block as stepping stone for future platforms
 46   log_warning(gc)("Shenandoah GC is not fully supported on this platform:");
 47   log_warning(gc)("  concurrent modes are not supported, only STW cycles are enabled;");

169   }
170 
171   if ((InitialHeapSize == MaxHeapSize) && ShenandoahUncommit) {
172     log_info(gc)("Min heap equals to max heap, disabling ShenandoahUncommit");
173     FLAG_SET_DEFAULT(ShenandoahUncommit, false);
174   }
175 
176   // If class unloading is disabled, no unloading for concurrent cycles as well.
177   if (!ClassUnloading) {
178     FLAG_SET_DEFAULT(ClassUnloadingWithConcurrentMark, false);
179   }
180 
181   // TLAB sizing policy makes resizing decisions before each GC cycle. It averages
182   // historical data, assigning more recent data the weight according to TLABAllocationWeight.
183   // Current default is good for generational collectors that run frequent young GCs.
184   // With Shenandoah, GC cycles are much less frequent, so we need we need sizing policy
185   // to converge faster over smaller number of resizing decisions.
186   if (FLAG_IS_DEFAULT(TLABAllocationWeight)) {
187     FLAG_SET_DEFAULT(TLABAllocationWeight, 90);
188   }
189 
190   FullGCForwarding::initialize_flags(MaxHeapSize);
191 }
192 
193 size_t ShenandoahArguments::conservative_max_heap_alignment() {
194   size_t align = ShenandoahMaxRegionSize;
195   if (UseLargePages) {
196     align = MAX2(align, os::large_page_size());
197   }
198   return align;
199 }
200 
201 void ShenandoahArguments::initialize_alignments() {
202   CardTable::initialize_card_size();
203 
204   // Need to setup sizes early to get correct alignments.
205   MaxHeapSize = ShenandoahHeapRegion::setup_sizes(MaxHeapSize);
206 
207   // This is expected by our algorithm for ShenandoahHeap::heap_region_containing().
208   size_t align = ShenandoahHeapRegion::region_size_bytes();
209   if (UseLargePages) {
210     align = MAX2(align, os::large_page_size());

  7  * under the terms of the GNU General Public License version 2 only, as
  8  * published by the Free Software Foundation.
  9  *
 10  * This code is distributed in the hope that it will be useful, but WITHOUT
 11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 13  * version 2 for more details (a copy is included in the LICENSE file that
 14  * accompanied this code).
 15  *
 16  * You should have received a copy of the GNU General Public License version
 17  * 2 along with this work; if not, write to the Free Software Foundation,
 18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 19  *
 20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 21  * or visit www.oracle.com if you need additional information or have any
 22  * questions.
 23  *
 24  */
 25 
 26 #include "precompiled.hpp"

 27 #include "gc/shared/gcArguments.hpp"
 28 #include "gc/shared/tlab_globals.hpp"
 29 #include "gc/shared/workerPolicy.hpp"
 30 #include "gc/shenandoah/shenandoahArguments.hpp"
 31 #include "gc/shenandoah/shenandoahCollectorPolicy.hpp"
 32 #include "gc/shenandoah/shenandoahGenerationalHeap.hpp"
 33 #include "gc/shenandoah/shenandoahHeap.inline.hpp"
 34 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
 35 #include "runtime/globals_extension.hpp"
 36 #include "runtime/java.hpp"
 37 #include "utilities/defaultStream.hpp"
 38 
 39 void ShenandoahArguments::initialize() {
 40 #if !(defined AARCH64 || defined AMD64 || defined IA32 || defined PPC64 || defined RISCV64)
 41   vm_exit_during_initialization("Shenandoah GC is not supported on this platform.");
 42 #endif
 43 
 44 #if 0 // leave this block as stepping stone for future platforms
 45   log_warning(gc)("Shenandoah GC is not fully supported on this platform:");
 46   log_warning(gc)("  concurrent modes are not supported, only STW cycles are enabled;");

168   }
169 
170   if ((InitialHeapSize == MaxHeapSize) && ShenandoahUncommit) {
171     log_info(gc)("Min heap equals to max heap, disabling ShenandoahUncommit");
172     FLAG_SET_DEFAULT(ShenandoahUncommit, false);
173   }
174 
175   // If class unloading is disabled, no unloading for concurrent cycles as well.
176   if (!ClassUnloading) {
177     FLAG_SET_DEFAULT(ClassUnloadingWithConcurrentMark, false);
178   }
179 
180   // TLAB sizing policy makes resizing decisions before each GC cycle. It averages
181   // historical data, assigning more recent data the weight according to TLABAllocationWeight.
182   // Current default is good for generational collectors that run frequent young GCs.
183   // With Shenandoah, GC cycles are much less frequent, so we need we need sizing policy
184   // to converge faster over smaller number of resizing decisions.
185   if (FLAG_IS_DEFAULT(TLABAllocationWeight)) {
186     FLAG_SET_DEFAULT(TLABAllocationWeight, 90);
187   }


188 }
189 
190 size_t ShenandoahArguments::conservative_max_heap_alignment() {
191   size_t align = ShenandoahMaxRegionSize;
192   if (UseLargePages) {
193     align = MAX2(align, os::large_page_size());
194   }
195   return align;
196 }
197 
198 void ShenandoahArguments::initialize_alignments() {
199   CardTable::initialize_card_size();
200 
201   // Need to setup sizes early to get correct alignments.
202   MaxHeapSize = ShenandoahHeapRegion::setup_sizes(MaxHeapSize);
203 
204   // This is expected by our algorithm for ShenandoahHeap::heap_region_containing().
205   size_t align = ShenandoahHeapRegion::region_size_bytes();
206   if (UseLargePages) {
207     align = MAX2(align, os::large_page_size());
< prev index next >