simplify heap.cpp by allocating segments pessimistically

This commit is contained in:
Joel Dice 2007-08-18 15:24:29 -06:00
parent 77136e77cb
commit 215a52ba54
6 changed files with 198 additions and 479 deletions

View File

@ -17,7 +17,7 @@ classpath = classpath
test = test
jscheme = /tmp/jscheme
input = $(cls)/Switch.class
input = $(cls)/GC.class
cxx = g++
cc = gcc
@ -129,7 +129,7 @@ classpath-objects = $(classpath-classes) $(jni-library)
class-name = $(patsubst $(cls)/%.class,%,$(1))
class-names = $(foreach x,$(1),$(call class-name,$(x)))
flags = -cp $(cls) -hs 67108864
flags = -cp $(cls)
args = $(flags) $(call class-name,$(input))
.PHONY: build
@ -147,7 +147,7 @@ debug: $(executable) $(input)
.PHONY: debug-jscheme
debug-jscheme: $(executable) $(input)
LD_LIBRARY_PATH=$(bld) gdb --args $(<) -cp $(cls):$(jscheme) -hs 67108864 \
LD_LIBRARY_PATH=$(bld) gdb --args $(<) -cp $(cls):$(jscheme) \
jscheme/REPL
.PHONY: vg
@ -156,7 +156,7 @@ vg: $(executable) $(input)
.PHONY: vg-jscheme
vg-jscheme: $(executable) $(input)
LD_LIBRARY_PATH=$(bld) $(vg) $(<) -cp $(cls):$(jscheme) -hs 67108864 \
LD_LIBRARY_PATH=$(bld) $(vg) $(<) -cp $(cls):$(jscheme) \
jscheme/REPL
.PHONY: test

View File

@ -2,19 +2,14 @@
#include "system.h"
#include "common.h"
#define CHAIN_HEADER_SIZE ceiling(sizeof(Segment::Chain), BytesPerWord)
using namespace vm;
namespace {
// an object must survive TenureThreshold + 2 garbage collections
// before being copied to gen2:
// before being copied to gen2 (muat be at least 1):
const unsigned TenureThreshold = 3;
const unsigned MinimumGen1SizeInBytes = 64 * 1024;
const unsigned MinimumGen2SizeInBytes = 128 * 1024;
const unsigned Top = ~static_cast<unsigned>(0);
const bool Verbose = true;
@ -22,10 +17,11 @@ const bool Debug = false;
class Context;
System* system(Context*);
void NO_RETURN abort(Context*);
void assert(Context*, bool);
System* system(Context*);
inline object
get(object o, unsigned offsetInWords)
{
@ -56,8 +52,6 @@ class Segment {
public:
class Map {
public:
class Chain;
class Iterator {
public:
Map* map;
@ -124,8 +118,8 @@ class Segment {
unsigned scale;
bool clearNewData;
Map(Segment* segment, unsigned bitsPerRecord = 1, unsigned scale = 1,
Map* child = 0, bool clearNewData = true):
Map(Segment* segment, unsigned bitsPerRecord, unsigned scale,
Map* child, bool clearNewData):
segment(segment),
child(child),
bitsPerRecord(bitsPerRecord),
@ -133,10 +127,18 @@ class Segment {
clearNewData(clearNewData)
{ }
void check() {
void init() {
assert(segment->context, bitsPerRecord);
assert(segment->context, scale);
assert(segment->context, powerOfTwo(scale));
if (clearNewData) {
memset(data(), 0, size() * BytesPerWord);
}
if (child) {
child->init();
}
}
void replaceWith(Map* m) {
@ -159,7 +161,7 @@ class Segment {
}
uintptr_t* data() {
return segment->rear->data() + segment->rear->capacity + offset();
return segment->data + segment->capacity() + offset();
}
unsigned size(unsigned capacity) {
@ -196,12 +198,6 @@ class Segment {
}
}
void clear() {
memset(data(), 0, size() * BytesPerWord);
if (child) child->clear();
}
void clearBit(unsigned i) {
assert(segment->context, wordOf(i) < size());
@ -275,130 +271,50 @@ class Segment {
}
};
class Chain {
public:
Segment* segment;
unsigned offset;
unsigned position;
unsigned capacity;
Chain* next;
Chain* previous;
Chain(Segment* segment, unsigned capacity, Chain* previous):
segment(segment),
offset(previous ? previous->offset + previous->position : 0),
position(0),
capacity(capacity),
next(0),
previous(previous)
{
assert(segment->context, sizeof(Chain) % BytesPerWord == 0);
}
static Chain* make(Segment* s, unsigned minimum, unsigned desired) {
assert(s->context, minimum > 0);
assert(s->context, desired >= minimum);
void* p = 0;
unsigned capacity = desired;
while (p == 0) {
p = system(s->context)->tryAllocate
(footprint(capacity, s->rear, s->map) * BytesPerWord);
if (p == 0) {
if (capacity > minimum) {
capacity = avg(minimum, capacity);
} else {
abort(s->context);
}
}
}
return new (p) Chain(s, capacity, s->rear);
}
static void dispose(Chain* c) {
if (c) {
if (c->next) dispose(c->next);
system(c->segment->context)->free(c);
}
}
uintptr_t* data() {
return reinterpret_cast<uintptr_t*>(this) + CHAIN_HEADER_SIZE;
}
static unsigned footprint(unsigned capacity, Chain* previous,
Map* map)
{
unsigned n = CHAIN_HEADER_SIZE + capacity;
if (map) {
unsigned segmentCapacity = capacity;
if (previous) {
segmentCapacity += previous->offset + previous->position;
}
n += map->footprint(segmentCapacity);
}
return n;
}
unsigned footprint() {
return footprint(capacity, previous, segment->map);
}
};
Context* context;
Chain* front;
Chain* rear;
uintptr_t* data;
unsigned position_;
unsigned capacity_;
Map* map;
Segment(Context* context, unsigned minimum, unsigned desired, Map* map = 0):
Segment(Context* context, Map* map, unsigned desired, unsigned minimum):
context(context),
front(0),
rear(0),
data(0),
position_(0),
capacity_(0),
map(map)
{
if (desired) {
front = rear = Chain::make(this, minimum, desired);
assert(context, minimum > 0);
assert(context, desired >= minimum);
capacity_ = desired;
while (data == 0) {
data = static_cast<uintptr_t*>
(system(context)->tryAllocate
((capacity_ + map->footprint(capacity_)) * BytesPerWord));
if (data == 0) {
if (capacity_ > minimum) {
capacity_ = avg(minimum, capacity_);
} else {
abort(context);
}
}
}
if (map) {
map->check();
if (map->clearNewData) {
memset(front->data() + front->capacity, 0,
map->footprint(front->capacity) * BytesPerWord);
}
map->init();
}
}
}
unsigned capacity() {
return (rear? rear->offset + rear->capacity : 0);
return capacity_;
}
unsigned position() {
return (rear? rear->offset + rear->position : 0);
}
void truncate(unsigned offset) {
assert(context, offset <= position());
for (Chain* c = front; c; c = c->next) {
if (offset >= c->offset
and offset <= c->offset + c->position)
{
c->position = offset - c->offset;
Chain::dispose(c->next);
return;
}
}
abort(context);
}
unsigned footprint() {
unsigned n = 0;
for (Chain* c = front; c; c = c->next) n += c->footprint();
return n;
return position_;
}
unsigned remaining() {
@ -406,12 +322,15 @@ class Segment {
}
void replaceWith(Segment* s) {
Chain::dispose(front);
system(context)->free(data);
data = s->data;
s->data = 0;
front = s->front;
rear = s->rear;
position_ = s->position_;
s->position_ = 0;
s->front = s->rear = 0;
capacity_ = s->capacity_;
s->capacity_ = 0;
if (s->map) {
if (map) {
@ -426,108 +345,39 @@ class Segment {
}
bool contains(void* p) {
for (Chain* c = front; c; c = c->next) {
if (c->position and p >= c->data() and p < c->data() + c->position) {
return true;
}
}
return false;
return position() and p >= data and p < data + position();
}
bool almostContains(void* p) {
return contains(p) or p == rear->data() + rear->position;
return contains(p) or p == data + position();
}
void* get(unsigned offset) {
for (Chain* c = front; c; c = c->next) {
if (c->position
and offset >= c->offset
and offset < c->offset + c->position)
{
return c->data() + (offset - c->offset);
}
}
if (offset == rear->offset + rear->position) {
return rear->data() + (offset - rear->offset);
}
abort(context);
assert(context, offset <= position());
return data + offset;
}
unsigned indexOf(void* p) {
for (Chain* c = front; c; c = c->next) {
if (c->position and p >= c->data() and p < c->data() + c->position) {
return (static_cast<uintptr_t*>(p) - c->data()) + c->offset;
}
}
if (p == rear->data() + rear->position) {
return (static_cast<uintptr_t*>(p) - rear->data()) + rear->offset;
}
abort(context);
assert(context, almostContains(p));
return static_cast<uintptr_t*>(p) - data;
}
void* allocate(unsigned size) {
assert(context, size);
assert(context, rear->position + size <= rear->capacity);
void* p = reinterpret_cast<void**>(rear->data()) + rear->position;
rear->position += size;
assert(context, position() + size <= capacity());
void* p = data + position();
position_ += size;
return p;
}
void ensure(unsigned minimum) {
if (remaining() < minimum) {
assert(context, rear->next == 0);
if (rear->position == 0) {
Chain* c = rear;
if (front == rear) {
front = rear = 0;
} else {
rear = rear->previous;
}
Chain::dispose(c);
}
unsigned desired = capacity() + minimum;
Chain* c = Chain::make(this, minimum, desired);
if (map) {
if (map->clearNewData) {
memset(c->data() + c->capacity, 0,
map->footprint(c->offset + c->capacity) * BytesPerWord);
}
map->update(c->data() + c->capacity, c->offset + c->capacity);
}
if (rear) {
rear->next = c;
rear = c;
} else {
front = rear = c;
}
}
}
void dispose() {
Chain::dispose(front);
front = rear = 0;
system(context)->free(data);
data = 0;
map = 0;
}
};
enum CollectionMode {
MinorCollection,
MajorCollection,
OverflowCollection,
Gen2Collection
};
class Context {
public:
Context(System* system):
@ -535,21 +385,27 @@ class Context {
client(0),
ageMap(&gen1, log(TenureThreshold), 1, 0, false),
gen1(this, 0, 0, &ageMap),
gen1(this, &ageMap, 0, 0),
nextAgeMap(&nextGen1, log(TenureThreshold), 1, 0, false),
nextGen1(this, 0, 0, &nextAgeMap),
nextGen1(this, &nextAgeMap, 0, 0),
pointerMap(&gen2),
pageMap(&gen2, 1, LikelyPageSizeInBytes / BytesPerWord, &pointerMap),
heapMap(&gen2, 1, pageMap.scale * 1024, &pageMap),
gen2(this, 0, 0, &heapMap),
pointerMap(&gen2, 1, 1, 0, true),
pageMap(&gen2, 1, LikelyPageSizeInBytes / BytesPerWord, &pointerMap, true),
heapMap(&gen2, 1, pageMap.scale * 1024, &pageMap, true),
gen2(this, &heapMap, 0, 0),
nextPointerMap(&nextGen2),
nextPointerMap(&nextGen2, 1, 1, 0, true),
nextPageMap(&nextGen2, 1, LikelyPageSizeInBytes / BytesPerWord,
&nextPointerMap),
nextHeapMap(&nextGen2, 1, nextPageMap.scale * 1024, &nextPageMap),
nextGen2(this, 0, 0, &nextHeapMap)
&nextPointerMap, true),
nextHeapMap(&nextGen2, 1, nextPageMap.scale * 1024, &nextPageMap, true),
nextGen2(this, &nextHeapMap, 0, 0),
gen2Base(0),
tenureFootprint(0),
gen1padding(0),
gen2padding(0),
mode(Heap::MinorCollection)
{ }
void dispose() {
@ -579,10 +435,20 @@ class Context {
Segment nextGen2;
unsigned gen2Base;
unsigned tenureFootprint;
unsigned gen1padding;
unsigned gen2padding;
CollectionMode mode;
Heap::CollectionType mode;
};
inline System*
system(Context* c)
{
return c->system;
}
const char*
segment(Context* c, void* p)
{
@ -599,12 +465,6 @@ segment(Context* c, void* p)
}
}
inline System*
system(Context* c)
{
return c->system;
}
inline void NO_RETURN
abort(Context* c)
{
@ -617,33 +477,17 @@ assert(Context* c, bool v)
assert(c->system, v);
}
void
initGen1(Context* c)
inline void
initNextGen1(Context* c, unsigned footprint)
{
unsigned minimum = MinimumGen1SizeInBytes / BytesPerWord;
unsigned desired = minimum;
new (&(c->ageMap)) Segment::Map
(&(c->gen1), log(TenureThreshold), 1, 0, false);
new (&(c->gen1)) Segment(c, minimum, desired, &(c->ageMap));
if (Verbose) {
fprintf(stderr, "init gen1 to %d bytes\n",
c->gen1.capacity() * BytesPerWord);
}
}
void
initNextGen1(Context* c)
{
unsigned minimum = MinimumGen1SizeInBytes / BytesPerWord;
unsigned desired = max(minimum, avg(c->gen1.position(), c->gen1.capacity()));
new (&(c->nextAgeMap)) Segment::Map
(&(c->nextGen1), log(TenureThreshold), 1, 0, false);
new (&(c->nextGen1)) Segment(c, minimum, desired, &(c->nextAgeMap));
unsigned minimum
= (c->gen1.position() - c->tenureFootprint) + footprint + c->gen1padding;
unsigned desired = minimum;
new (&(c->nextGen1)) Segment(c, &(c->nextAgeMap), desired, minimum);
if (Verbose) {
fprintf(stderr, "init nextGen1 to %d bytes\n",
@ -651,40 +495,23 @@ initNextGen1(Context* c)
}
}
void
initGen2(Context* c)
{
unsigned minimum = MinimumGen2SizeInBytes / BytesPerWord;
unsigned desired = minimum;
new (&(c->pointerMap)) Segment::Map(&(c->gen2));
new (&(c->pageMap)) Segment::Map
(&(c->gen2), 1, LikelyPageSizeInBytes / BytesPerWord, &(c->pointerMap));
new (&(c->heapMap)) Segment::Map
(&(c->gen2), 1, c->pageMap.scale * 1024, &(c->pageMap));
new (&(c->gen2)) Segment(c, minimum, desired, &(c->heapMap));
if (Verbose) {
fprintf(stderr, "init gen2 to %d bytes\n",
c->gen2.capacity() * BytesPerWord);
}
}
void
inline void
initNextGen2(Context* c)
{
unsigned minimum = MinimumGen2SizeInBytes / BytesPerWord;
unsigned desired = max(minimum, avg(c->gen2.position(), c->gen2.capacity()));
new (&(c->nextPointerMap)) Segment::Map
(&(c->nextGen2), 1, 1, 0, true);
new (&(c->nextPointerMap)) Segment::Map(&(c->nextGen2));
new (&(c->nextPageMap)) Segment::Map
(&(c->nextGen2), 1, LikelyPageSizeInBytes / BytesPerWord,
&(c->nextPointerMap));
new (&(c->nextHeapMap)) Segment::Map
(&(c->nextGen2), 1, c->pageMap.scale * 1024, &(c->nextPageMap));
&(c->nextPointerMap), true);
new (&(c->nextGen2)) Segment(c, minimum, desired, &(c->nextHeapMap));
new (&(c->nextHeapMap)) Segment::Map
(&(c->nextGen2), 1, c->pageMap.scale * 1024, &(c->nextPageMap), true);
unsigned minimum = c->gen2.position() + c->tenureFootprint + c->gen2padding;
unsigned desired = minimum * 2;
new (&(c->nextGen2)) Segment(c, &(c->nextHeapMap), desired, minimum);
if (Verbose) {
fprintf(stderr, "init nextGen2 to %d bytes\n",
@ -730,25 +557,7 @@ bitset(Context* c, object o)
inline object
copyTo(Context* c, Segment* s, object o, unsigned size)
{
if (s->remaining() < size) {
s->ensure(size);
if (Verbose) {
if (s == &(c->gen2)) {
fprintf(stderr, "grow gen2 to %d bytes\n",
c->gen2.capacity() * BytesPerWord);
} else if (s == &(c->nextGen1)) {
fprintf(stderr, "grow nextGen1 to %d bytes\n",
c->nextGen1.capacity() * BytesPerWord);
} else if (s == &(c->nextGen2)) {
fprintf(stderr, "grow nextGen2 to %d bytes\n",
c->nextGen2.capacity() * BytesPerWord);
} else {
abort(c);
}
}
}
assert(c, s->remaining() >= size);
object dst = s->allocate(size);
c->client->copy(o, dst);
return dst;
@ -760,37 +569,31 @@ copy2(Context* c, object o)
unsigned size = c->client->copiedSizeInWords(o);
if (c->gen2.contains(o)) {
assert(c, c->mode == MajorCollection
or c->mode == Gen2Collection);
assert(c, c->mode == Heap::MajorCollection);
return copyTo(c, &(c->nextGen2), o, size);
} else if (c->gen1.contains(o)) {
unsigned age = c->ageMap.get(o);
if (age == TenureThreshold) {
if (c->mode == MinorCollection) {
if (c->gen2.front == 0) initGen2(c);
if (c->mode == Heap::MinorCollection) {
assert(c, c->gen2.remaining() >= size);
if (c->gen2.remaining() >= size) {
if (c->gen2Base == Top) {
c->gen2Base = c->gen2.position();
}
return copyTo(c, &(c->gen2), o, size);
} else {
if (Verbose) {
fprintf(stderr, "overflow collection\n");
}
c->mode = OverflowCollection;
initNextGen2(c);
return copyTo(c, &(c->nextGen2), o, size);
if (c->gen2Base == Top) {
c->gen2Base = c->gen2.position();
}
return copyTo(c, &(c->gen2), o, size);
} else {
return copyTo(c, &(c->nextGen2), o, size);
}
} else {
o = copyTo(c, &(c->nextGen1), o, size);
c->nextAgeMap.setOnly(o, age + 1);
if (age + 1 == TenureThreshold) {
c->tenureFootprint += size;
}
return o;
}
} else {
@ -836,27 +639,9 @@ update3(Context* c, object o, bool* needsVisit)
object
update2(Context* c, object o, bool* needsVisit)
{
switch (c->mode) {
case MinorCollection:
case OverflowCollection:
if (c->gen2.contains(o)) {
*needsVisit = false;
return o;
}
break;
case Gen2Collection:
if (c->gen2.contains(o)) {
return update3(c, o, needsVisit);
} else {
assert(c, c->nextGen1.contains(o) or c->nextGen2.contains(o));
*needsVisit = false;
return o;
}
break;
default: break;
if (c->mode == Heap::MinorCollection and c->gen2.contains(o)) {
*needsVisit = false;
return o;
}
return update3(c, o, needsVisit);
@ -874,7 +659,7 @@ update(Context* c, object* p, bool* needsVisit)
// update heap map.
if (r) {
if (c->mode == MinorCollection) {
if (c->mode == Heap::MinorCollection) {
if (c->gen2.contains(p) and not c->gen2.contains(r)) {
if (Debug) {
fprintf(stderr, "mark %p (%s) at %p (%s)\n",
@ -1204,7 +989,7 @@ collect(Context* c, Segment::Map* map, unsigned start, unsigned end,
map->clearOnly(s);
bool childDirty = false;
collect(c, map->child, s, e, &childDirty, true);
if (c->mode != OverflowCollection and childDirty) {
if (childDirty) {
map->setOnly(s);
*dirty = true;
}
@ -1219,7 +1004,7 @@ collect(Context* c, Segment::Map* map, unsigned start, unsigned end,
} else {
collect(c, p);
if (c->mode != OverflowCollection and not c->gen2.contains(*p)) {
if (not c->gen2.contains(*p)) {
map->setOnly(p);
*dirty = true;
}
@ -1230,78 +1015,19 @@ collect(Context* c, Segment::Map* map, unsigned start, unsigned end,
assert(c, wasDirty or not expectDirty);
}
class ObjectSegmentIterator {
public:
Context* context;
Segment::Chain* chain;
unsigned index;
unsigned end;
bool dirty;
ObjectSegmentIterator(Segment* segment, unsigned end):
context(segment->context),
chain(segment->front),
index(0),
end(end),
dirty(false)
{ }
bool hasNext() {
if (dirty) {
dirty = false;
uintptr_t* p = chain->data() + index;
index += context->client->sizeInWords(p);
}
if (chain and index == chain->position) {
chain = chain->next;
index = 0;
}
return chain and index + chain->offset < end;
}
object next() {
dirty = true;
return chain->data() + index;
}
};
void
collect(Context* c, Segment* s, unsigned limit)
{
for (ObjectSegmentIterator it(s, limit); it.hasNext();) {
object p = it.next();
class Walker : public Heap::Walker {
public:
Walker(Context* c, object p): c(c), p(p) { }
virtual bool visit(unsigned offset) {
collect(c, getp(p, offset));
return true;
}
Context* c;
object p;
} walker(c, p);
c->client->walk(p, &walker);
}
}
void
collect2(Context* c)
{
if (c->mode == MinorCollection and c->gen2.position()) {
c->gen2Base = Top;
c->tenureFootprint = 0;
c->gen1padding = 0;
c->gen2padding = 0;
if (c->mode == Heap::MinorCollection and c->gen2.position()) {
unsigned start = 0;
unsigned end = start + c->gen2.position();
bool dirty;
collect(c, &(c->heapMap), start, end, &dirty, false);
} else if (c->mode == Gen2Collection) {
unsigned ng2Position = c->nextGen2.position();
collect(c, &(c->nextGen1), c->nextGen1.position());
collect(c, &(c->nextGen2), ng2Position);
}
class Visitor : public Heap::Visitor {
@ -1319,58 +1045,30 @@ collect2(Context* c)
}
void
collect(Context* c)
collect(Context* c, unsigned footprint)
{
if (c->gen1.front == 0) initGen1(c);
if (c->tenureFootprint > c->gen2.remaining()) {
c->mode = Heap::MajorCollection;
}
c->gen2Base = Top;
switch (c->mode) {
case MinorCollection: {
initNextGen1(c);
if (Verbose) {
if (Verbose) {
if (c->mode == Heap::MajorCollection) {
fprintf(stderr, "major collection\n");
} else {
fprintf(stderr, "minor collection\n");
}
}
collect2(c);
if (c->mode == OverflowCollection) {
c->mode = Gen2Collection;
if (Verbose) {
fprintf(stderr, "gen2 collection\n");
}
c->gen2Base = Top;
collect2(c);
c->gen2.replaceWith(&(c->nextGen2));
}
c->gen1.replaceWith(&(c->nextGen1));
} break;
case MajorCollection: {
initNextGen1(c);
initNextGen1(c, footprint);
if (c->mode == Heap::MajorCollection) {
initNextGen2(c);
if (c->gen2.position()) {
c->heapMap.clear();
}
}
if (Verbose) {
fprintf(stderr, "major collection\n");
}
collect2(c);
collect2(c);
c->gen1.replaceWith(&(c->nextGen1));
c->gen2.replaceWith(&(c->nextGen2));
} break;
default: abort(c);
c->gen1.replaceWith(&(c->nextGen1));
if (c->mode == Heap::MajorCollection) {
c->gen2.replaceWith(&(c->nextGen2));
}
}
@ -1378,22 +1076,12 @@ class MyHeap: public Heap {
public:
MyHeap(System* system): c(system) { }
virtual void collect(CollectionType type, Client* client) {
switch (type) {
case MinorCollection:
c.mode = ::MinorCollection;
break;
case MajorCollection:
c.mode = ::MajorCollection;
break;
default: abort(&c);
}
virtual void collect(CollectionType type, Client* client, unsigned footprint)
{
c.mode = type;
c.client = client;
::collect(&c);
::collect(&c, footprint);
}
virtual bool needsMark(void** p) {
@ -1409,9 +1097,18 @@ class MyHeap: public Heap {
c.heapMap.set(p);
}
virtual void dispose() {
c.dispose();
c.system->free(this);
virtual void pad(void* p, unsigned extra) {
if (c.gen1.contains(p)) {
if (c.ageMap.get(p) == TenureThreshold) {
c.gen2padding += extra;
} else {
c.gen1padding += extra;
}
} else if (c.gen2.contains(p)) {
c.gen2padding += extra;
} else {
c.gen1padding += extra;
}
}
virtual void* follow(void* p) {
@ -1437,8 +1134,7 @@ class MyHeap: public Heap {
return Reachable;
} else if (c.nextGen2.contains(p)
or (c.gen2.contains(p)
and (c.mode == ::MinorCollection
or c.mode == ::OverflowCollection
and (c.mode == Heap::MinorCollection
or c.gen2.indexOf(p) >= c.gen2Base)))
{
return Tenured;
@ -1450,11 +1146,12 @@ class MyHeap: public Heap {
}
virtual CollectionType collectionType() {
if (c.mode == ::MinorCollection) {
return MinorCollection;
} else {
return MajorCollection;
}
return c.mode;
}
virtual void dispose() {
c.dispose();
c.system->free(this);
}
Context c;

View File

@ -42,9 +42,11 @@ class Heap {
};
virtual ~Heap() { }
virtual void collect(CollectionType type, Client* client) = 0;
virtual void collect(CollectionType type, Client* client, unsigned footprint)
= 0;
virtual bool needsMark(void** p) = 0;
virtual void mark(void** p) = 0;
virtual void pad(void* p, unsigned extra) = 0;
virtual void* follow(void* p) = 0;
virtual Status status(void* p) = 0;
virtual CollectionType collectionType() = 0;

View File

@ -111,6 +111,23 @@ killZombies(Thread* t, Thread* o)
}
}
unsigned
footprint(Thread* t)
{
unsigned n = t->heapIndex;
if (t->large) {
n += extendedSize
(t, t->large, baseSize(t, t->large, objectClass(t, t->large)));
}
for (Thread* c = t->child; c; c = c->peer) {
n += footprint(c);
}
return n;
}
void
visitRoots(Thread* t, Heap::Visitor* v)
{
@ -2498,7 +2515,7 @@ collect(Thread* t, Heap::CollectionType type)
} it(m);
m->unsafe = true;
m->heap->collect(type, &it);
m->heap->collect(type, &it, footprint(m->rootThread));
m->unsafe = false;
postCollect(m->rootThread);

View File

@ -1885,6 +1885,9 @@ markHashTaken(Thread* t, object o)
{
assert(t, not objectExtended(t, o));
cast<uintptr_t>(o, 0) |= HashTakenMark;
ACQUIRE_RAW(t, t->vm->heapLock);
t->vm->heap->pad(o, 1);
}
inline uint32_t

View File

@ -38,7 +38,7 @@ usageAndExit(const char* name)
int
main(int ac, const char** av)
{
unsigned heapSize = 4 * 1024 * 1024;
unsigned heapSize = 128 * 1024 * 1024;
const char* path = ".";
const char* class_ = 0;
int argc = 0;