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src/hotspot/share/memory/metaspace.cpp
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rev 57380 : [mq]: metaspace-improvement
@@ -29,12 +29,12 @@
#include "logging/log.hpp"
#include "logging/logStream.hpp"
#include "memory/filemap.hpp"
#include "memory/metaspace.hpp"
#include "memory/metaspace/chunkManager.hpp"
+#include "memory/metaspace/chunkLevel.hpp"
#include "memory/metaspace/metachunk.hpp"
-#include "memory/metaspace/metaspaceCommon.hpp"
#include "memory/metaspace/printCLDMetaspaceInfoClosure.hpp"
#include "memory/metaspace/spaceManager.hpp"
#include "memory/metaspace/virtualSpaceList.hpp"
#include "memory/metaspaceShared.hpp"
#include "memory/metaspaceTracer.hpp"
@@ -57,302 +57,12 @@
size_t Metaspace::_compressed_class_space_size;
const MetaspaceTracer* Metaspace::_tracer = NULL;
DEBUG_ONLY(bool Metaspace::_frozen = false;)
-static const char* space_type_name(Metaspace::MetaspaceType t) {
- const char* s = NULL;
- switch (t) {
- case Metaspace::StandardMetaspaceType: s = "Standard"; break;
- case Metaspace::BootMetaspaceType: s = "Boot"; break;
- case Metaspace::UnsafeAnonymousMetaspaceType: s = "UnsafeAnonymous"; break;
- case Metaspace::ReflectionMetaspaceType: s = "Reflection"; break;
- default: ShouldNotReachHere();
- }
- return s;
-}
-
-volatile size_t MetaspaceGC::_capacity_until_GC = 0;
-uint MetaspaceGC::_shrink_factor = 0;
-bool MetaspaceGC::_should_concurrent_collect = false;
-
-// BlockFreelist methods
-
-// VirtualSpaceNode methods
-
-// MetaspaceGC methods
-
-// VM_CollectForMetadataAllocation is the vm operation used to GC.
-// Within the VM operation after the GC the attempt to allocate the metadata
-// should succeed. If the GC did not free enough space for the metaspace
-// allocation, the HWM is increased so that another virtualspace will be
-// allocated for the metadata. With perm gen the increase in the perm
-// gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The
-// metaspace policy uses those as the small and large steps for the HWM.
-//
-// After the GC the compute_new_size() for MetaspaceGC is called to
-// resize the capacity of the metaspaces. The current implementation
-// is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used
-// to resize the Java heap by some GC's. New flags can be implemented
-// if really needed. MinMetaspaceFreeRatio is used to calculate how much
-// free space is desirable in the metaspace capacity to decide how much
-// to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much
-// free space is desirable in the metaspace capacity before decreasing
-// the HWM.
-
-// Calculate the amount to increase the high water mark (HWM).
-// Increase by a minimum amount (MinMetaspaceExpansion) so that
-// another expansion is not requested too soon. If that is not
-// enough to satisfy the allocation, increase by MaxMetaspaceExpansion.
-// If that is still not enough, expand by the size of the allocation
-// plus some.
-size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) {
- size_t min_delta = MinMetaspaceExpansion;
- size_t max_delta = MaxMetaspaceExpansion;
- size_t delta = align_up(bytes, Metaspace::commit_alignment());
-
- if (delta <= min_delta) {
- delta = min_delta;
- } else if (delta <= max_delta) {
- // Don't want to hit the high water mark on the next
- // allocation so make the delta greater than just enough
- // for this allocation.
- delta = max_delta;
- } else {
- // This allocation is large but the next ones are probably not
- // so increase by the minimum.
- delta = delta + min_delta;
- }
-
- assert_is_aligned(delta, Metaspace::commit_alignment());
-
- return delta;
-}
-
-size_t MetaspaceGC::capacity_until_GC() {
- size_t value = OrderAccess::load_acquire(&_capacity_until_GC);
- assert(value >= MetaspaceSize, "Not initialized properly?");
- return value;
-}
-
-// Try to increase the _capacity_until_GC limit counter by v bytes.
-// Returns true if it succeeded. It may fail if either another thread
-// concurrently increased the limit or the new limit would be larger
-// than MaxMetaspaceSize.
-// On success, optionally returns new and old metaspace capacity in
-// new_cap_until_GC and old_cap_until_GC respectively.
-// On error, optionally sets can_retry to indicate whether if there is
-// actually enough space remaining to satisfy the request.
-bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC, bool* can_retry) {
- assert_is_aligned(v, Metaspace::commit_alignment());
-
- size_t old_capacity_until_GC = _capacity_until_GC;
- size_t new_value = old_capacity_until_GC + v;
-
- if (new_value < old_capacity_until_GC) {
- // The addition wrapped around, set new_value to aligned max value.
- new_value = align_down(max_uintx, Metaspace::commit_alignment());
- }
-
- if (new_value > MaxMetaspaceSize) {
- if (can_retry != NULL) {
- *can_retry = false;
- }
- return false;
- }
-
- if (can_retry != NULL) {
- *can_retry = true;
- }
- size_t prev_value = Atomic::cmpxchg(new_value, &_capacity_until_GC, old_capacity_until_GC);
-
- if (old_capacity_until_GC != prev_value) {
- return false;
- }
- if (new_cap_until_GC != NULL) {
- *new_cap_until_GC = new_value;
- }
- if (old_cap_until_GC != NULL) {
- *old_cap_until_GC = old_capacity_until_GC;
- }
- return true;
-}
-size_t MetaspaceGC::dec_capacity_until_GC(size_t v) {
- assert_is_aligned(v, Metaspace::commit_alignment());
-
- return Atomic::sub(v, &_capacity_until_GC);
-}
-
-void MetaspaceGC::initialize() {
- // Set the high-water mark to MaxMetapaceSize during VM initializaton since
- // we can't do a GC during initialization.
- _capacity_until_GC = MaxMetaspaceSize;
-}
-
-void MetaspaceGC::post_initialize() {
- // Reset the high-water mark once the VM initialization is done.
- _capacity_until_GC = MAX2(MetaspaceUtils::committed_bytes(), MetaspaceSize);
-}
-
-bool MetaspaceGC::can_expand(size_t word_size, bool is_class) {
- // Check if the compressed class space is full.
- if (is_class && Metaspace::using_class_space()) {
- size_t class_committed = MetaspaceUtils::committed_bytes(Metaspace::ClassType);
- if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) {
- log_trace(gc, metaspace, freelist)("Cannot expand %s metaspace by " SIZE_FORMAT " words (CompressedClassSpaceSize = " SIZE_FORMAT " words)",
- (is_class ? "class" : "non-class"), word_size, CompressedClassSpaceSize / sizeof(MetaWord));
- return false;
- }
- }
-
- // Check if the user has imposed a limit on the metaspace memory.
- size_t committed_bytes = MetaspaceUtils::committed_bytes();
- if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) {
- log_trace(gc, metaspace, freelist)("Cannot expand %s metaspace by " SIZE_FORMAT " words (MaxMetaspaceSize = " SIZE_FORMAT " words)",
- (is_class ? "class" : "non-class"), word_size, MaxMetaspaceSize / sizeof(MetaWord));
- return false;
- }
-
- return true;
-}
-
-size_t MetaspaceGC::allowed_expansion() {
- size_t committed_bytes = MetaspaceUtils::committed_bytes();
- size_t capacity_until_gc = capacity_until_GC();
-
- assert(capacity_until_gc >= committed_bytes,
- "capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT,
- capacity_until_gc, committed_bytes);
-
- size_t left_until_max = MaxMetaspaceSize - committed_bytes;
- size_t left_until_GC = capacity_until_gc - committed_bytes;
- size_t left_to_commit = MIN2(left_until_GC, left_until_max);
- log_trace(gc, metaspace, freelist)("allowed expansion words: " SIZE_FORMAT
- " (left_until_max: " SIZE_FORMAT ", left_until_GC: " SIZE_FORMAT ".",
- left_to_commit / BytesPerWord, left_until_max / BytesPerWord, left_until_GC / BytesPerWord);
-
- return left_to_commit / BytesPerWord;
-}
-
-void MetaspaceGC::compute_new_size() {
- assert(_shrink_factor <= 100, "invalid shrink factor");
- uint current_shrink_factor = _shrink_factor;
- _shrink_factor = 0;
-
- // Using committed_bytes() for used_after_gc is an overestimation, since the
- // chunk free lists are included in committed_bytes() and the memory in an
- // un-fragmented chunk free list is available for future allocations.
- // However, if the chunk free lists becomes fragmented, then the memory may
- // not be available for future allocations and the memory is therefore "in use".
- // Including the chunk free lists in the definition of "in use" is therefore
- // necessary. Not including the chunk free lists can cause capacity_until_GC to
- // shrink below committed_bytes() and this has caused serious bugs in the past.
- const size_t used_after_gc = MetaspaceUtils::committed_bytes();
- const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC();
-
- const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0;
- const double maximum_used_percentage = 1.0 - minimum_free_percentage;
-
- const double min_tmp = used_after_gc / maximum_used_percentage;
- size_t minimum_desired_capacity =
- (size_t)MIN2(min_tmp, double(MaxMetaspaceSize));
- // Don't shrink less than the initial generation size
- minimum_desired_capacity = MAX2(minimum_desired_capacity,
- MetaspaceSize);
-
- log_trace(gc, metaspace)("MetaspaceGC::compute_new_size: ");
- log_trace(gc, metaspace)(" minimum_free_percentage: %6.2f maximum_used_percentage: %6.2f",
- minimum_free_percentage, maximum_used_percentage);
- log_trace(gc, metaspace)(" used_after_gc : %6.1fKB", used_after_gc / (double) K);
-
-
- size_t shrink_bytes = 0;
- if (capacity_until_GC < minimum_desired_capacity) {
- // If we have less capacity below the metaspace HWM, then
- // increment the HWM.
- size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
- expand_bytes = align_up(expand_bytes, Metaspace::commit_alignment());
- // Don't expand unless it's significant
- if (expand_bytes >= MinMetaspaceExpansion) {
- size_t new_capacity_until_GC = 0;
- bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC);
- assert(succeeded, "Should always succesfully increment HWM when at safepoint");
-
- Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
- new_capacity_until_GC,
- MetaspaceGCThresholdUpdater::ComputeNewSize);
- log_trace(gc, metaspace)(" expanding: minimum_desired_capacity: %6.1fKB expand_bytes: %6.1fKB MinMetaspaceExpansion: %6.1fKB new metaspace HWM: %6.1fKB",
- minimum_desired_capacity / (double) K,
- expand_bytes / (double) K,
- MinMetaspaceExpansion / (double) K,
- new_capacity_until_GC / (double) K);
- }
- return;
- }
-
- // No expansion, now see if we want to shrink
- // We would never want to shrink more than this
- assert(capacity_until_GC >= minimum_desired_capacity,
- SIZE_FORMAT " >= " SIZE_FORMAT,
- capacity_until_GC, minimum_desired_capacity);
- size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity;
-
- // Should shrinking be considered?
- if (MaxMetaspaceFreeRatio < 100) {
- const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0;
- const double minimum_used_percentage = 1.0 - maximum_free_percentage;
- const double max_tmp = used_after_gc / minimum_used_percentage;
- size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(MaxMetaspaceSize));
- maximum_desired_capacity = MAX2(maximum_desired_capacity,
- MetaspaceSize);
- log_trace(gc, metaspace)(" maximum_free_percentage: %6.2f minimum_used_percentage: %6.2f",
- maximum_free_percentage, minimum_used_percentage);
- log_trace(gc, metaspace)(" minimum_desired_capacity: %6.1fKB maximum_desired_capacity: %6.1fKB",
- minimum_desired_capacity / (double) K, maximum_desired_capacity / (double) K);
-
- assert(minimum_desired_capacity <= maximum_desired_capacity,
- "sanity check");
-
- if (capacity_until_GC > maximum_desired_capacity) {
- // Capacity too large, compute shrinking size
- shrink_bytes = capacity_until_GC - maximum_desired_capacity;
- // We don't want shrink all the way back to initSize if people call
- // System.gc(), because some programs do that between "phases" and then
- // we'd just have to grow the heap up again for the next phase. So we
- // damp the shrinking: 0% on the first call, 10% on the second call, 40%
- // on the third call, and 100% by the fourth call. But if we recompute
- // size without shrinking, it goes back to 0%.
- shrink_bytes = shrink_bytes / 100 * current_shrink_factor;
-
- shrink_bytes = align_down(shrink_bytes, Metaspace::commit_alignment());
-
- assert(shrink_bytes <= max_shrink_bytes,
- "invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
- shrink_bytes, max_shrink_bytes);
- if (current_shrink_factor == 0) {
- _shrink_factor = 10;
- } else {
- _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100);
- }
- log_trace(gc, metaspace)(" shrinking: initThreshold: %.1fK maximum_desired_capacity: %.1fK",
- MetaspaceSize / (double) K, maximum_desired_capacity / (double) K);
- log_trace(gc, metaspace)(" shrink_bytes: %.1fK current_shrink_factor: %d new shrink factor: %d MinMetaspaceExpansion: %.1fK",
- shrink_bytes / (double) K, current_shrink_factor, _shrink_factor, MinMetaspaceExpansion / (double) K);
- }
- }
-
- // Don't shrink unless it's significant
- if (shrink_bytes >= MinMetaspaceExpansion &&
- ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) {
- size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes);
- Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
- new_capacity_until_GC,
- MetaspaceGCThresholdUpdater::ComputeNewSize);
- }
-}
// MetaspaceUtils
size_t MetaspaceUtils::_capacity_words [Metaspace:: MetadataTypeCount] = {0, 0};
size_t MetaspaceUtils::_overhead_words [Metaspace:: MetadataTypeCount] = {0, 0};
volatile size_t MetaspaceUtils::_used_words [Metaspace:: MetadataTypeCount] = {0, 0};
@@ -529,368 +239,10 @@
reserved_bytes(ct)/K);
}
}
-void MetaspaceUtils::print_vs(outputStream* out, size_t scale) {
- const size_t reserved_nonclass_words = reserved_bytes(Metaspace::NonClassType) / sizeof(MetaWord);
- const size_t committed_nonclass_words = committed_bytes(Metaspace::NonClassType) / sizeof(MetaWord);
- {
- if (Metaspace::using_class_space()) {
- out->print(" Non-class space: ");
- }
- print_scaled_words(out, reserved_nonclass_words, scale, 7);
- out->print(" reserved, ");
- print_scaled_words_and_percentage(out, committed_nonclass_words, reserved_nonclass_words, scale, 7);
- out->print_cr(" committed ");
-
- if (Metaspace::using_class_space()) {
- const size_t reserved_class_words = reserved_bytes(Metaspace::ClassType) / sizeof(MetaWord);
- const size_t committed_class_words = committed_bytes(Metaspace::ClassType) / sizeof(MetaWord);
- out->print(" Class space: ");
- print_scaled_words(out, reserved_class_words, scale, 7);
- out->print(" reserved, ");
- print_scaled_words_and_percentage(out, committed_class_words, reserved_class_words, scale, 7);
- out->print_cr(" committed ");
-
- const size_t reserved_words = reserved_nonclass_words + reserved_class_words;
- const size_t committed_words = committed_nonclass_words + committed_class_words;
- out->print(" Both: ");
- print_scaled_words(out, reserved_words, scale, 7);
- out->print(" reserved, ");
- print_scaled_words_and_percentage(out, committed_words, reserved_words, scale, 7);
- out->print_cr(" committed ");
- }
- }
-}
-
-static void print_basic_switches(outputStream* out, size_t scale) {
- out->print("MaxMetaspaceSize: ");
- if (MaxMetaspaceSize >= (max_uintx) - (2 * os::vm_page_size())) {
- // aka "very big". Default is max_uintx, but due to rounding in arg parsing the real
- // value is smaller.
- out->print("unlimited");
- } else {
- print_human_readable_size(out, MaxMetaspaceSize, scale);
- }
- out->cr();
- if (Metaspace::using_class_space()) {
- out->print("CompressedClassSpaceSize: ");
- print_human_readable_size(out, CompressedClassSpaceSize, scale);
- }
- out->cr();
-}
-
-// This will print out a basic metaspace usage report but
-// unlike print_report() is guaranteed not to lock or to walk the CLDG.
-void MetaspaceUtils::print_basic_report(outputStream* out, size_t scale) {
-
- if (!Metaspace::initialized()) {
- out->print_cr("Metaspace not yet initialized.");
- return;
- }
-
- out->cr();
- out->print_cr("Usage:");
-
- if (Metaspace::using_class_space()) {
- out->print(" Non-class: ");
- }
-
- // In its most basic form, we do not require walking the CLDG. Instead, just print the running totals from
- // MetaspaceUtils.
- const size_t cap_nc = MetaspaceUtils::capacity_words(Metaspace::NonClassType);
- const size_t overhead_nc = MetaspaceUtils::overhead_words(Metaspace::NonClassType);
- const size_t used_nc = MetaspaceUtils::used_words(Metaspace::NonClassType);
- const size_t free_and_waste_nc = cap_nc - overhead_nc - used_nc;
-
- print_scaled_words(out, cap_nc, scale, 5);
- out->print(" capacity, ");
- print_scaled_words_and_percentage(out, used_nc, cap_nc, scale, 5);
- out->print(" used, ");
- print_scaled_words_and_percentage(out, free_and_waste_nc, cap_nc, scale, 5);
- out->print(" free+waste, ");
- print_scaled_words_and_percentage(out, overhead_nc, cap_nc, scale, 5);
- out->print(" overhead. ");
- out->cr();
-
- if (Metaspace::using_class_space()) {
- const size_t cap_c = MetaspaceUtils::capacity_words(Metaspace::ClassType);
- const size_t overhead_c = MetaspaceUtils::overhead_words(Metaspace::ClassType);
- const size_t used_c = MetaspaceUtils::used_words(Metaspace::ClassType);
- const size_t free_and_waste_c = cap_c - overhead_c - used_c;
- out->print(" Class: ");
- print_scaled_words(out, cap_c, scale, 5);
- out->print(" capacity, ");
- print_scaled_words_and_percentage(out, used_c, cap_c, scale, 5);
- out->print(" used, ");
- print_scaled_words_and_percentage(out, free_and_waste_c, cap_c, scale, 5);
- out->print(" free+waste, ");
- print_scaled_words_and_percentage(out, overhead_c, cap_c, scale, 5);
- out->print(" overhead. ");
- out->cr();
-
- out->print(" Both: ");
- const size_t cap = cap_nc + cap_c;
-
- print_scaled_words(out, cap, scale, 5);
- out->print(" capacity, ");
- print_scaled_words_and_percentage(out, used_nc + used_c, cap, scale, 5);
- out->print(" used, ");
- print_scaled_words_and_percentage(out, free_and_waste_nc + free_and_waste_c, cap, scale, 5);
- out->print(" free+waste, ");
- print_scaled_words_and_percentage(out, overhead_nc + overhead_c, cap, scale, 5);
- out->print(" overhead. ");
- out->cr();
- }
-
- out->cr();
- out->print_cr("Virtual space:");
-
- print_vs(out, scale);
-
- out->cr();
- out->print_cr("Chunk freelists:");
-
- if (Metaspace::using_class_space()) {
- out->print(" Non-Class: ");
- }
- print_human_readable_size(out, Metaspace::chunk_manager_metadata()->free_chunks_total_bytes(), scale);
- out->cr();
- if (Metaspace::using_class_space()) {
- out->print(" Class: ");
- print_human_readable_size(out, Metaspace::chunk_manager_class()->free_chunks_total_bytes(), scale);
- out->cr();
- out->print(" Both: ");
- print_human_readable_size(out, Metaspace::chunk_manager_class()->free_chunks_total_bytes() +
- Metaspace::chunk_manager_metadata()->free_chunks_total_bytes(), scale);
- out->cr();
- }
-
- out->cr();
-
- // Print basic settings
- print_basic_switches(out, scale);
-
- out->cr();
-
-}
-
-void MetaspaceUtils::print_report(outputStream* out, size_t scale, int flags) {
-
- if (!Metaspace::initialized()) {
- out->print_cr("Metaspace not yet initialized.");
- return;
- }
-
- const bool print_loaders = (flags & rf_show_loaders) > 0;
- const bool print_classes = (flags & rf_show_classes) > 0;
- const bool print_by_chunktype = (flags & rf_break_down_by_chunktype) > 0;
- const bool print_by_spacetype = (flags & rf_break_down_by_spacetype) > 0;
-
- // Some report options require walking the class loader data graph.
- PrintCLDMetaspaceInfoClosure cl(out, scale, print_loaders, print_classes, print_by_chunktype);
- if (print_loaders) {
- out->cr();
- out->print_cr("Usage per loader:");
- out->cr();
- }
-
- ClassLoaderDataGraph::loaded_cld_do(&cl); // collect data and optionally print
-
- // Print totals, broken up by space type.
- if (print_by_spacetype) {
- out->cr();
- out->print_cr("Usage per space type:");
- out->cr();
- for (int space_type = (int)Metaspace::ZeroMetaspaceType;
- space_type < (int)Metaspace::MetaspaceTypeCount; space_type ++)
- {
- uintx num_loaders = cl._num_loaders_by_spacetype[space_type];
- uintx num_classes = cl._num_classes_by_spacetype[space_type];
- out->print("%s - " UINTX_FORMAT " %s",
- space_type_name((Metaspace::MetaspaceType)space_type),
- num_loaders, loaders_plural(num_loaders));
- if (num_classes > 0) {
- out->print(", ");
- print_number_of_classes(out, num_classes, cl._num_classes_shared_by_spacetype[space_type]);
- out->print(":");
- cl._stats_by_spacetype[space_type].print_on(out, scale, print_by_chunktype);
- } else {
- out->print(".");
- out->cr();
- }
- out->cr();
- }
- }
-
- // Print totals for in-use data:
- out->cr();
- {
- uintx num_loaders = cl._num_loaders;
- out->print("Total Usage - " UINTX_FORMAT " %s, ",
- num_loaders, loaders_plural(num_loaders));
- print_number_of_classes(out, cl._num_classes, cl._num_classes_shared);
- out->print(":");
- cl._stats_total.print_on(out, scale, print_by_chunktype);
- out->cr();
- }
-
- // -- Print Virtual space.
- out->cr();
- out->print_cr("Virtual space:");
-
- print_vs(out, scale);
-
- // -- Print VirtualSpaceList details.
- if ((flags & rf_show_vslist) > 0) {
- out->cr();
- out->print_cr("Virtual space list%s:", Metaspace::using_class_space() ? "s" : "");
-
- if (Metaspace::using_class_space()) {
- out->print_cr(" Non-Class:");
- }
- Metaspace::space_list()->print_on(out, scale);
- if (Metaspace::using_class_space()) {
- out->print_cr(" Class:");
- Metaspace::class_space_list()->print_on(out, scale);
- }
- }
- out->cr();
-
- // -- Print VirtualSpaceList map.
- if ((flags & rf_show_vsmap) > 0) {
- out->cr();
- out->print_cr("Virtual space map:");
-
- if (Metaspace::using_class_space()) {
- out->print_cr(" Non-Class:");
- }
- Metaspace::space_list()->print_map(out);
- if (Metaspace::using_class_space()) {
- out->print_cr(" Class:");
- Metaspace::class_space_list()->print_map(out);
- }
- }
- out->cr();
-
- // -- Print Freelists (ChunkManager) details
- out->cr();
- out->print_cr("Chunk freelist%s:", Metaspace::using_class_space() ? "s" : "");
-
- ChunkManagerStatistics non_class_cm_stat;
- Metaspace::chunk_manager_metadata()->collect_statistics(&non_class_cm_stat);
-
- if (Metaspace::using_class_space()) {
- out->print_cr(" Non-Class:");
- }
- non_class_cm_stat.print_on(out, scale);
-
- if (Metaspace::using_class_space()) {
- ChunkManagerStatistics class_cm_stat;
- Metaspace::chunk_manager_class()->collect_statistics(&class_cm_stat);
- out->print_cr(" Class:");
- class_cm_stat.print_on(out, scale);
- }
-
- // As a convenience, print a summary of common waste.
- out->cr();
- out->print("Waste ");
- // For all wastages, print percentages from total. As total use the total size of memory committed for metaspace.
- const size_t committed_words = committed_bytes() / BytesPerWord;
-
- out->print("(percentages refer to total committed size ");
- print_scaled_words(out, committed_words, scale);
- out->print_cr("):");
-
- // Print space committed but not yet used by any class loader
- const size_t unused_words_in_vs = MetaspaceUtils::free_in_vs_bytes() / BytesPerWord;
- out->print(" Committed unused: ");
- print_scaled_words_and_percentage(out, unused_words_in_vs, committed_words, scale, 6);
- out->cr();
-
- // Print waste for in-use chunks.
- UsedChunksStatistics ucs_nonclass = cl._stats_total.nonclass_sm_stats().totals();
- UsedChunksStatistics ucs_class = cl._stats_total.class_sm_stats().totals();
- UsedChunksStatistics ucs_all;
- ucs_all.add(ucs_nonclass);
- ucs_all.add(ucs_class);
-
- out->print(" Waste in chunks in use: ");
- print_scaled_words_and_percentage(out, ucs_all.waste(), committed_words, scale, 6);
- out->cr();
- out->print(" Free in chunks in use: ");
- print_scaled_words_and_percentage(out, ucs_all.free(), committed_words, scale, 6);
- out->cr();
- out->print(" Overhead in chunks in use: ");
- print_scaled_words_and_percentage(out, ucs_all.overhead(), committed_words, scale, 6);
- out->cr();
-
- // Print waste in free chunks.
- const size_t total_capacity_in_free_chunks =
- Metaspace::chunk_manager_metadata()->free_chunks_total_words() +
- (Metaspace::using_class_space() ? Metaspace::chunk_manager_class()->free_chunks_total_words() : 0);
- out->print(" In free chunks: ");
- print_scaled_words_and_percentage(out, total_capacity_in_free_chunks, committed_words, scale, 6);
- out->cr();
-
- // Print waste in deallocated blocks.
- const uintx free_blocks_num =
- cl._stats_total.nonclass_sm_stats().free_blocks_num() +
- cl._stats_total.class_sm_stats().free_blocks_num();
- const size_t free_blocks_cap_words =
- cl._stats_total.nonclass_sm_stats().free_blocks_cap_words() +
- cl._stats_total.class_sm_stats().free_blocks_cap_words();
- out->print("Deallocated from chunks in use: ");
- print_scaled_words_and_percentage(out, free_blocks_cap_words, committed_words, scale, 6);
- out->print(" (" UINTX_FORMAT " blocks)", free_blocks_num);
- out->cr();
-
- // Print total waste.
- const size_t total_waste = ucs_all.waste() + ucs_all.free() + ucs_all.overhead() + total_capacity_in_free_chunks
- + free_blocks_cap_words + unused_words_in_vs;
- out->print(" -total-: ");
- print_scaled_words_and_percentage(out, total_waste, committed_words, scale, 6);
- out->cr();
-
- // Print internal statistics
-#ifdef ASSERT
- out->cr();
- out->cr();
- out->print_cr("Internal statistics:");
- out->cr();
- out->print_cr("Number of allocations: " UINTX_FORMAT ".", g_internal_statistics.num_allocs);
- out->print_cr("Number of space births: " UINTX_FORMAT ".", g_internal_statistics.num_metaspace_births);
- out->print_cr("Number of space deaths: " UINTX_FORMAT ".", g_internal_statistics.num_metaspace_deaths);
- out->print_cr("Number of virtual space node births: " UINTX_FORMAT ".", g_internal_statistics.num_vsnodes_created);
- out->print_cr("Number of virtual space node deaths: " UINTX_FORMAT ".", g_internal_statistics.num_vsnodes_purged);
- out->print_cr("Number of times virtual space nodes were expanded: " UINTX_FORMAT ".", g_internal_statistics.num_committed_space_expanded);
- out->print_cr("Number of deallocations: " UINTX_FORMAT " (" UINTX_FORMAT " external).", g_internal_statistics.num_deallocs, g_internal_statistics.num_external_deallocs);
- out->print_cr("Allocations from deallocated blocks: " UINTX_FORMAT ".", g_internal_statistics.num_allocs_from_deallocated_blocks);
- out->print_cr("Number of chunks added to freelist: " UINTX_FORMAT ".",
- g_internal_statistics.num_chunks_added_to_freelist);
- out->print_cr("Number of chunks removed from freelist: " UINTX_FORMAT ".",
- g_internal_statistics.num_chunks_removed_from_freelist);
- out->print_cr("Number of chunk merges: " UINTX_FORMAT ", split-ups: " UINTX_FORMAT ".",
- g_internal_statistics.num_chunk_merges, g_internal_statistics.num_chunk_splits);
-
- out->cr();
-#endif
-
- // Print some interesting settings
- out->cr();
- out->cr();
- print_basic_switches(out, scale);
-
- out->cr();
- out->print("InitialBootClassLoaderMetaspaceSize: ");
- print_human_readable_size(out, InitialBootClassLoaderMetaspaceSize, scale);
-
- out->cr();
- out->cr();
-
-} // MetaspaceUtils::print_report()
// Prints an ASCII representation of the given space.
void MetaspaceUtils::print_metaspace_map(outputStream* out, Metaspace::MetadataType mdtype) {
MutexLocker cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag);
const bool for_class = mdtype == Metaspace::ClassType ? true : false;
@@ -955,16 +307,10 @@
#endif
}
// Metaspace methods
-size_t Metaspace::_first_chunk_word_size = 0;
-size_t Metaspace::_first_class_chunk_word_size = 0;
-
-size_t Metaspace::_commit_alignment = 0;
-size_t Metaspace::_reserve_alignment = 0;
-
VirtualSpaceList* Metaspace::_space_list = NULL;
VirtualSpaceList* Metaspace::_class_space_list = NULL;
ChunkManager* Metaspace::_chunk_manager_metadata = NULL;
ChunkManager* Metaspace::_chunk_manager_class = NULL;
@@ -1176,16 +522,13 @@
void Metaspace::initialize_class_space(ReservedSpace rs) {
// The reserved space size may be bigger because of alignment, esp with UseLargePages
assert(rs.size() >= CompressedClassSpaceSize,
SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize);
assert(using_class_space(), "Must be using class space");
- _class_space_list = new VirtualSpaceList(rs);
- _chunk_manager_class = new ChunkManager(true/*is_class*/);
+ _class_space_list = new VirtualSpaceList("class space list", rs);
+ _chunk_manager_class = new ChunkManager("class space chunk manager", _class_space_list);
- if (!_class_space_list->initialization_succeeded()) {
- vm_exit_during_initialization("Failed to setup compressed class space virtual space list.");
- }
}
#endif
void Metaspace::ergo_initialize() {
@@ -1198,11 +541,16 @@
if (UseLargePages && UseLargePagesInMetaspace) {
page_size = os::large_page_size();
}
_commit_alignment = page_size;
- _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity());
+
+ // Reserve alignment: all Metaspace memory mappings are to be aligned to the size of a root chunk.
+ assert(is_aligned_to((int)MAX_CHUNK_BYTE_SIZE, os::vm_allocation_granularity()),
+ "root chunk size must be a multiple of alloc granularity");
+
+ _reserve_alignment = MAX2(page_size, (size_t)MAX_CHUNK_BYTE_SIZE);
// Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will
// override if MaxMetaspaceSize was set on the command line or not.
// This information is needed later to conform to the specification of the
// java.lang.management.MemoryUsage API.
@@ -1244,11 +592,11 @@
set_compressed_class_space_size(CompressedClassSpaceSize);
}
void Metaspace::global_initialize() {
- MetaspaceGC::initialize();
+ MetaspaceGC::initialize(); // <- since we do not prealloc init chunks anymore is this still needed?
#if INCLUDE_CDS
if (DumpSharedSpaces) {
MetaspaceShared::initialize_dumptime_shared_and_meta_spaces();
} else if (UseSharedSpaces) {
@@ -1260,43 +608,25 @@
}
if (DynamicDumpSharedSpaces && !UseSharedSpaces) {
vm_exit_during_initialization("DynamicDumpSharedSpaces is unsupported when base CDS archive is not loaded", NULL);
}
-
- if (!DumpSharedSpaces && !UseSharedSpaces)
#endif // INCLUDE_CDS
- {
+
+ // Initialize class space:
+ if (CDS_ONLY(!DumpSharedSpaces && !UseSharedSpaces) NOT_CDS(true)) {
#ifdef _LP64
if (using_class_space()) {
char* base = (char*)align_up(Universe::heap()->reserved_region().end(), _reserve_alignment);
allocate_metaspace_compressed_klass_ptrs(base, 0);
}
#endif // _LP64
}
- // Initialize these before initializing the VirtualSpaceList
- _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord;
- _first_chunk_word_size = align_word_size_up(_first_chunk_word_size);
- // Make the first class chunk bigger than a medium chunk so it's not put
- // on the medium chunk list. The next chunk will be small and progress
- // from there. This size calculated by -version.
- _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6,
- (CompressedClassSpaceSize/BytesPerWord)*2);
- _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size);
- // Arbitrarily set the initial virtual space to a multiple
- // of the boot class loader size.
- size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size;
- word_size = align_up(word_size, Metaspace::reserve_alignment_words());
-
- // Initialize the list of virtual spaces.
- _space_list = new VirtualSpaceList(word_size);
- _chunk_manager_metadata = new ChunkManager(false/*metaspace*/);
-
- if (!_space_list->initialization_succeeded()) {
- vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL);
- }
+ // Initialize non-class virtual space list, and its chunk manager:
+ _space_list = new VirtualSpaceList("Non-Class VirtualSpaceList");
+ _chunk_manager_metadata = new ChunkManager("Non-Class ChunkManager", _space_list);
_tracer = new MetaspaceTracer();
_initialized = true;
@@ -1314,14 +644,10 @@
assert(class_space_list() != NULL, "Class VirtualSpaceList has not been initialized");
assert(chunk_manager_class() != NULL, "Class ChunkManager has not been initialized");
}
}
-size_t Metaspace::align_word_size_up(size_t word_size) {
- size_t byte_size = word_size * wordSize;
- return ReservedSpace::allocation_align_size_up(byte_size) / wordSize;
-}
MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size,
MetaspaceObj::Type type, TRAPS) {
assert(!_frozen, "sanity");
assert(!(DumpSharedSpaces && THREAD->is_VM_thread()), "sanity");
@@ -1458,178 +784,10 @@
}
return get_space_list(NonClassType)->contains(ptr);
}
-// ClassLoaderMetaspace
-
-ClassLoaderMetaspace::ClassLoaderMetaspace(Mutex* lock, Metaspace::MetaspaceType type)
- : _space_type(type)
- , _lock(lock)
- , _vsm(NULL)
- , _class_vsm(NULL)
-{
- initialize(lock, type);
-}
-
-ClassLoaderMetaspace::~ClassLoaderMetaspace() {
- Metaspace::assert_not_frozen();
- DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_metaspace_deaths));
- delete _vsm;
- if (Metaspace::using_class_space()) {
- delete _class_vsm;
- }
-}
-
-void ClassLoaderMetaspace::initialize_first_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype) {
- Metachunk* chunk = get_initialization_chunk(type, mdtype);
- if (chunk != NULL) {
- // Add to this manager's list of chunks in use and make it the current_chunk().
- get_space_manager(mdtype)->add_chunk(chunk, true);
- }
-}
-
-Metachunk* ClassLoaderMetaspace::get_initialization_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype) {
- size_t chunk_word_size = get_space_manager(mdtype)->get_initial_chunk_size(type);
-
- // Get a chunk from the chunk freelist
- Metachunk* chunk = Metaspace::get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size);
-
- if (chunk == NULL) {
- chunk = Metaspace::get_space_list(mdtype)->get_new_chunk(chunk_word_size,
- get_space_manager(mdtype)->medium_chunk_bunch());
- }
-
- return chunk;
-}
-
-void ClassLoaderMetaspace::initialize(Mutex* lock, Metaspace::MetaspaceType type) {
- Metaspace::verify_global_initialization();
-
- DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_metaspace_births));
-
- // Allocate SpaceManager for metadata objects.
- _vsm = new SpaceManager(Metaspace::NonClassType, type, lock);
-
- if (Metaspace::using_class_space()) {
- // Allocate SpaceManager for classes.
- _class_vsm = new SpaceManager(Metaspace::ClassType, type, lock);
- }
-
- MutexLocker cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag);
-
- // Allocate chunk for metadata objects
- initialize_first_chunk(type, Metaspace::NonClassType);
-
- // Allocate chunk for class metadata objects
- if (Metaspace::using_class_space()) {
- initialize_first_chunk(type, Metaspace::ClassType);
- }
-}
-
-MetaWord* ClassLoaderMetaspace::allocate(size_t word_size, Metaspace::MetadataType mdtype) {
- Metaspace::assert_not_frozen();
-
- DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_allocs));
-
- // Don't use class_vsm() unless UseCompressedClassPointers is true.
- if (Metaspace::is_class_space_allocation(mdtype)) {
- return class_vsm()->allocate(word_size);
- } else {
- return vsm()->allocate(word_size);
- }
-}
-
-MetaWord* ClassLoaderMetaspace::expand_and_allocate(size_t word_size, Metaspace::MetadataType mdtype) {
- Metaspace::assert_not_frozen();
- size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord);
- assert(delta_bytes > 0, "Must be");
-
- size_t before = 0;
- size_t after = 0;
- bool can_retry = true;
- MetaWord* res;
- bool incremented;
-
- // Each thread increments the HWM at most once. Even if the thread fails to increment
- // the HWM, an allocation is still attempted. This is because another thread must then
- // have incremented the HWM and therefore the allocation might still succeed.
- do {
- incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before, &can_retry);
- res = allocate(word_size, mdtype);
- } while (!incremented && res == NULL && can_retry);
-
- if (incremented) {
- Metaspace::tracer()->report_gc_threshold(before, after,
- MetaspaceGCThresholdUpdater::ExpandAndAllocate);
- log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after);
- }
-
- return res;
-}
-
-size_t ClassLoaderMetaspace::allocated_blocks_bytes() const {
- return (vsm()->used_words() +
- (Metaspace::using_class_space() ? class_vsm()->used_words() : 0)) * BytesPerWord;
-}
-
-size_t ClassLoaderMetaspace::allocated_chunks_bytes() const {
- return (vsm()->capacity_words() +
- (Metaspace::using_class_space() ? class_vsm()->capacity_words() : 0)) * BytesPerWord;
-}
-
-void ClassLoaderMetaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
- Metaspace::assert_not_frozen();
- assert(!SafepointSynchronize::is_at_safepoint()
- || Thread::current()->is_VM_thread(), "should be the VM thread");
-
- DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_external_deallocs));
-
- MutexLocker ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
-
- if (is_class && Metaspace::using_class_space()) {
- class_vsm()->deallocate(ptr, word_size);
- } else {
- vsm()->deallocate(ptr, word_size);
- }
-}
-
-size_t ClassLoaderMetaspace::class_chunk_size(size_t word_size) {
- assert(Metaspace::using_class_space(), "Has to use class space");
- return class_vsm()->calc_chunk_size(word_size);
-}
-
-void ClassLoaderMetaspace::print_on(outputStream* out) const {
- // Print both class virtual space counts and metaspace.
- if (Verbose) {
- vsm()->print_on(out);
- if (Metaspace::using_class_space()) {
- class_vsm()->print_on(out);
- }
- }
-}
-
-void ClassLoaderMetaspace::verify() {
- vsm()->verify();
- if (Metaspace::using_class_space()) {
- class_vsm()->verify();
- }
-}
-
-void ClassLoaderMetaspace::add_to_statistics_locked(ClassLoaderMetaspaceStatistics* out) const {
- assert_lock_strong(lock());
- vsm()->add_to_statistics_locked(&out->nonclass_sm_stats());
- if (Metaspace::using_class_space()) {
- class_vsm()->add_to_statistics_locked(&out->class_sm_stats());
- }
-}
-
-void ClassLoaderMetaspace::add_to_statistics(ClassLoaderMetaspaceStatistics* out) const {
- MutexLocker cl(lock(), Mutex::_no_safepoint_check_flag);
- add_to_statistics_locked(out);
-}
-
/////////////// Unit tests ///////////////
struct chunkmanager_statistics_t {
int num_specialized_chunks;
int num_small_chunks;
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