drlvm/vm/gc_gen/src/common/space_tuner.h

/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

/**
 * @author Xiao-Feng Li, 2006/10/05
 */

#ifndef _SPACE_TUNER_H_
#define _SPACE_TUNER_H_

#include "gc_common.h"
#include "gc_space.h"

#define GC_LOS_MIN_VARY_SIZE ( 2 * MB )
//#define GC_FIXED_SIZE_TUNER

extern POINTER_SIZE_INT max_heap_size_bytes;

//For_LOS_extend
enum Transform_Kind {
  TRANS_NOTHING = 0,
  TRANS_FROM_LOS_TO_MOS = 0x1,
  TRANS_FROM_MOS_TO_LOS = 0x2,
};

typedef struct Space_Tuner{
    Transform_Kind kind;
    /*This flags is set if the tuning direction changes in the process of tuning*/
    Boolean reverse;
    
    POINTER_SIZE_INT tuning_size;
    /*Used for LOS_Shrink*/
    Block_Header* interim_blocks;
    /*This flag is set when tuning strategy decide to tune los size.
      *i.e. wasted memory is greater than wast_threshold.  */
    Boolean need_tune;
    /*This flag is set if gc is caused by los alloc failure.*/
    Boolean force_tune;
    
    uint64 speed_los;
    uint64 last_speed_los;

    uint64 speed_mos;
    uint64 last_speed_mos;

    uint64 speed_nos;
    uint64 last_speed_nos;
        
    /*Total wasted memory of los science last los variation*/
    uint64 wast_los;
    /*Total wasted memory of mos science last los variation*/
    uint64 wast_mos;

    uint64 current_dw;
    /*NOS survive size of last minor, this could be the least meaningful space unit when talking about tuning.*/
    POINTER_SIZE_INT current_ds;

    /*Threshold for deta waste*/
    POINTER_SIZE_INT threshold_waste;
    /*Minimun tuning size for los variation*/
    POINTER_SIZE_INT min_tuning_size;
}Space_Tuner;

void gc_compute_space_tune_size_before_marking(GC* gc);
void gc_compute_space_tune_size_after_marking(GC *gc);
void gc_space_tuner_reset(GC* gc);
void gc_space_tuner_initialize(GC* gc);
void gc_space_tuner_init_fake_blocks_for_los_shrink(GC* gc);
void gc_space_tuner_release_fake_blocks_for_los_shrink(GC* gc);

inline Boolean gc_has_space_tuner(GC* gc)
{ return (Boolean)(POINTER_SIZE_INT)gc->tuner; }

#endif /* _SPACE_TUNER_H_ */