8213108: Improve work distribution during remembered set scan
Summary: Before scanning the heap for roots into the collection set, merge them into a single remembered set (card table) and do work distribution based on location like other collectors do.
Reviewed-by: kbarrett, lkorinth
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* 2 along with this work; if not, write to the Free Software Foundation,
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#ifndef SHARE_GC_SHARED_WORKERDATAARRAY_INLINE_HPP
#define SHARE_GC_SHARED_WORKERDATAARRAY_INLINE_HPP
#include "gc/shared/workerDataArray.hpp"
#include "memory/allocation.inline.hpp"
#include "utilities/ostream.hpp"
template <typename T>
WorkerDataArray<T>::WorkerDataArray(uint length, const char* title) :
_data(NULL),
_length(length),
_title(title) {
assert(length > 0, "Must have some workers to store data for");
_data = NEW_C_HEAP_ARRAY(T, _length, mtGC);
for (uint i = 0; i < MaxThreadWorkItems; i++) {
_thread_work_items[i] = NULL;
}
reset();
}
template <typename T>
void WorkerDataArray<T>::set(uint worker_i, T value) {
assert(worker_i < _length, "Worker %d is greater than max: %d", worker_i, _length);
assert(_data[worker_i] == uninitialized(), "Overwriting data for worker %d in %s", worker_i, _title);
_data[worker_i] = value;
}
template <typename T>
T WorkerDataArray<T>::get(uint worker_i) const {
assert(worker_i < _length, "Worker %d is greater than max: %d", worker_i, _length);
return _data[worker_i];
}
template <typename T>
WorkerDataArray<T>::~WorkerDataArray() {
FREE_C_HEAP_ARRAY(T, _data);
}
template <typename T>
void WorkerDataArray<T>::link_thread_work_items(WorkerDataArray<size_t>* thread_work_items, uint index) {
assert(index < MaxThreadWorkItems, "Tried to access thread work item %u (max %u)", index, MaxThreadWorkItems);
_thread_work_items[index] = thread_work_items;
}
template <typename T>
void WorkerDataArray<T>::set_thread_work_item(uint worker_i, size_t value, uint index) {
assert(index < MaxThreadWorkItems, "Tried to access thread work item %u (max %u)", index, MaxThreadWorkItems);
assert(_thread_work_items[index] != NULL, "No sub count");
_thread_work_items[index]->set(worker_i, value);
}
template <typename T>
void WorkerDataArray<T>::add_thread_work_item(uint worker_i, size_t value, uint index) {
assert(index < MaxThreadWorkItems, "Tried to access thread work item %u (max %u)", index, MaxThreadWorkItems);
assert(_thread_work_items[index] != NULL, "No sub count");
_thread_work_items[index]->add(worker_i, value);
}
template <typename T>
void WorkerDataArray<T>::set_or_add_thread_work_item(uint worker_i, size_t value, uint index) {
assert(index < MaxThreadWorkItems, "Tried to access thread work item %u (max %u)", index, MaxThreadWorkItems);
assert(_thread_work_items[index] != NULL, "No sub count");
if (_thread_work_items[index]->get(worker_i) == _thread_work_items[index]->uninitialized()) {
_thread_work_items[index]->set(worker_i, value);
} else {
_thread_work_items[index]->add(worker_i, value);
}
}
template <typename T>
size_t WorkerDataArray<T>::get_thread_work_item(uint worker_i, uint index) {
assert(index < MaxThreadWorkItems, "Tried to access thread work item %u (max %u)", index, MaxThreadWorkItems);
assert(_thread_work_items[index] != NULL, "No sub count");
return _thread_work_items[index]->get(worker_i);
}
template <typename T>
void WorkerDataArray<T>::add(uint worker_i, T value) {
assert(worker_i < _length, "Worker %d is greater than max: %d", worker_i, _length);
assert(_data[worker_i] != uninitialized(), "No data to add to %s for worker %d", _title, worker_i);
_data[worker_i] += value;
}
template <typename T>
double WorkerDataArray<T>::average() const {
uint contributing_threads = 0;
for (uint i = 0; i < _length; ++i) {
if (get(i) != uninitialized()) {
contributing_threads++;
}
}
if (contributing_threads == 0) {
return 0.0;
}
return sum() / (double) contributing_threads;
}
template <typename T>
T WorkerDataArray<T>::sum() const {
T s = 0;
for (uint i = 0; i < _length; ++i) {
if (get(i) != uninitialized()) {
s += get(i);
}
}
return s;
}
template <typename T>
void WorkerDataArray<T>::set_all(T value) {
for (uint i = 0; i < _length; i++) {
_data[i] = value;
}
}
template <class T>
void WorkerDataArray<T>::print_summary_on(outputStream* out, bool print_sum) const {
out->print("%-25s", title());
uint start = 0;
while (start < _length && get(start) == uninitialized()) {
start++;
}
if (start < _length) {
T min = get(start);
T max = min;
T sum = 0;
uint contributing_threads = 0;
for (uint i = start; i < _length; ++i) {
T value = get(i);
if (value != uninitialized()) {
max = MAX2(max, value);
min = MIN2(min, value);
sum += value;
contributing_threads++;
}
}
T diff = max - min;
assert(contributing_threads != 0, "Must be since we found a used value for the start index");
double avg = sum / (double) contributing_threads;
WDAPrinter::summary(out, min, avg, max, diff, sum, print_sum);
out->print_cr(", Workers: %d", contributing_threads);
} else {
// No data for this phase.
out->print_cr(" skipped");
}
}
template <class T>
void WorkerDataArray<T>::print_details_on(outputStream* out) const {
WDAPrinter::details(this, out);
}
template <typename T>
void WorkerDataArray<T>::reset() {
set_all(uninitialized());
for (uint i = 0; i < MaxThreadWorkItems; i++) {
if (_thread_work_items[i] != NULL) {
_thread_work_items[i]->reset();
}
}
}
#endif // SHARE_GC_SHARED_WORKERDATAARRAY_INLINE_HPP