Mercurial > hg > truffle
diff src/share/vm/gc_implementation/parallelScavenge/parallelScavengeHeap.cpp @ 6725:da91efe96a93
6964458: Reimplement class meta-data storage to use native memory
Summary: Remove PermGen, allocate meta-data in metaspace linked to class loaders, rewrite GC walking, rewrite and rename metadata to be C++ classes
Reviewed-by: jmasa, stefank, never, coleenp, kvn, brutisso, mgerdin, dholmes, jrose, twisti, roland
Contributed-by: jmasa <jon.masamitsu@oracle.com>, stefank <stefan.karlsson@oracle.com>, mgerdin <mikael.gerdin@oracle.com>, never <tom.rodriguez@oracle.com>
author | coleenp |
---|---|
date | Sat, 01 Sep 2012 13:25:18 -0400 |
parents | d2a62e0f25eb |
children | 82657b6a8cc0 |
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line diff
--- a/src/share/vm/gc_implementation/parallelScavenge/parallelScavengeHeap.cpp Fri Aug 31 16:39:35 2012 -0700 +++ b/src/share/vm/gc_implementation/parallelScavenge/parallelScavengeHeap.cpp Sat Sep 01 13:25:18 2012 -0400 @@ -45,26 +45,23 @@ PSYoungGen* ParallelScavengeHeap::_young_gen = NULL; PSOldGen* ParallelScavengeHeap::_old_gen = NULL; -PSPermGen* ParallelScavengeHeap::_perm_gen = NULL; PSAdaptiveSizePolicy* ParallelScavengeHeap::_size_policy = NULL; PSGCAdaptivePolicyCounters* ParallelScavengeHeap::_gc_policy_counters = NULL; ParallelScavengeHeap* ParallelScavengeHeap::_psh = NULL; GCTaskManager* ParallelScavengeHeap::_gc_task_manager = NULL; static void trace_gen_sizes(const char* const str, - size_t pg_min, size_t pg_max, size_t og_min, size_t og_max, size_t yg_min, size_t yg_max) { if (TracePageSizes) { tty->print_cr("%s: " SIZE_FORMAT "," SIZE_FORMAT " " SIZE_FORMAT "," SIZE_FORMAT " " - SIZE_FORMAT "," SIZE_FORMAT " " SIZE_FORMAT, - str, pg_min / K, pg_max / K, + str, og_min / K, og_max / K, yg_min / K, yg_max / K, - (pg_max + og_max + yg_max) / K); + (og_max + yg_max) / K); } } @@ -79,25 +76,15 @@ size_t yg_max_size = _collector_policy->max_young_gen_size(); size_t og_min_size = _collector_policy->min_old_gen_size(); size_t og_max_size = _collector_policy->max_old_gen_size(); - // Why isn't there a min_perm_gen_size()? - size_t pg_min_size = _collector_policy->perm_gen_size(); - size_t pg_max_size = _collector_policy->max_perm_gen_size(); trace_gen_sizes("ps heap raw", - pg_min_size, pg_max_size, og_min_size, og_max_size, yg_min_size, yg_max_size); - // The ReservedSpace ctor used below requires that the page size for the perm - // gen is <= the page size for the rest of the heap (young + old gens). const size_t og_page_sz = os::page_size_for_region(yg_min_size + og_min_size, yg_max_size + og_max_size, 8); - const size_t pg_page_sz = MIN2(os::page_size_for_region(pg_min_size, - pg_max_size, 16), - og_page_sz); - const size_t pg_align = set_alignment(_perm_gen_alignment, pg_page_sz); const size_t og_align = set_alignment(_old_gen_alignment, og_page_sz); const size_t yg_align = set_alignment(_young_gen_alignment, og_page_sz); @@ -121,55 +108,20 @@ align_size_down(_collector_policy->old_gen_size(), og_align); og_cur_size = MAX2(og_cur_size, og_min_size); - pg_min_size = align_size_up(pg_min_size, pg_align); - pg_max_size = align_size_up(pg_max_size, pg_align); - size_t pg_cur_size = pg_min_size; - trace_gen_sizes("ps heap rnd", - pg_min_size, pg_max_size, og_min_size, og_max_size, yg_min_size, yg_max_size); - const size_t total_reserved = pg_max_size + og_max_size + yg_max_size; - char* addr = Universe::preferred_heap_base(total_reserved, Universe::UnscaledNarrowOop); - - // The main part of the heap (old gen + young gen) can often use a larger page - // size than is needed or wanted for the perm gen. Use the "compound - // alignment" ReservedSpace ctor to avoid having to use the same page size for - // all gens. - - ReservedHeapSpace heap_rs(pg_max_size, pg_align, og_max_size + yg_max_size, - og_align, addr); + const size_t heap_size = og_max_size + yg_max_size; - if (UseCompressedOops) { - if (addr != NULL && !heap_rs.is_reserved()) { - // Failed to reserve at specified address - the requested memory - // region is taken already, for example, by 'java' launcher. - // Try again to reserver heap higher. - addr = Universe::preferred_heap_base(total_reserved, Universe::ZeroBasedNarrowOop); - ReservedHeapSpace heap_rs0(pg_max_size, pg_align, og_max_size + yg_max_size, - og_align, addr); - if (addr != NULL && !heap_rs0.is_reserved()) { - // Failed to reserve at specified address again - give up. - addr = Universe::preferred_heap_base(total_reserved, Universe::HeapBasedNarrowOop); - assert(addr == NULL, ""); - ReservedHeapSpace heap_rs1(pg_max_size, pg_align, og_max_size + yg_max_size, - og_align, addr); - heap_rs = heap_rs1; - } else { - heap_rs = heap_rs0; - } - } - } + ReservedSpace heap_rs = Universe::reserve_heap(heap_size, og_align); MemTracker::record_virtual_memory_type((address)heap_rs.base(), mtJavaHeap); - os::trace_page_sizes("ps perm", pg_min_size, pg_max_size, pg_page_sz, - heap_rs.base(), pg_max_size); os::trace_page_sizes("ps main", og_min_size + yg_min_size, og_max_size + yg_max_size, og_page_sz, - heap_rs.base() + pg_max_size, - heap_rs.size() - pg_max_size); + heap_rs.base(), + heap_rs.size()); if (!heap_rs.is_reserved()) { vm_shutdown_during_initialization( "Could not reserve enough space for object heap"); @@ -194,11 +146,6 @@ const size_t init_young_size = align_size_up(4 * M, yg_align); yg_cur_size = MAX2(MIN2(init_young_size, yg_max_size), yg_cur_size); - // Split the reserved space into perm gen and the main heap (everything else). - // The main heap uses a different alignment. - ReservedSpace perm_rs = heap_rs.first_part(pg_max_size); - ReservedSpace main_rs = heap_rs.last_part(pg_max_size, og_align); - // Make up the generations // Calculate the maximum size that a generation can grow. This // includes growth into the other generation. Note that the @@ -208,7 +155,7 @@ double max_gc_pause_sec = ((double) MaxGCPauseMillis)/1000.0; double max_gc_minor_pause_sec = ((double) MaxGCMinorPauseMillis)/1000.0; - _gens = new AdjoiningGenerations(main_rs, + _gens = new AdjoiningGenerations(heap_rs, og_cur_size, og_min_size, og_max_size, @@ -233,13 +180,6 @@ GCTimeRatio ); - _perm_gen = new PSPermGen(perm_rs, - pg_align, - pg_cur_size, - pg_cur_size, - pg_max_size, - "perm", 2); - assert(!UseAdaptiveGCBoundary || (old_gen()->virtual_space()->high_boundary() == young_gen()->virtual_space()->low_boundary()), @@ -273,7 +213,7 @@ void ParallelScavengeHeap::update_counters() { young_gen()->update_counters(); old_gen()->update_counters(); - perm_gen()->update_counters(); + MetaspaceCounters::update_performance_counters(); } size_t ParallelScavengeHeap::capacity() const { @@ -291,17 +231,8 @@ } -size_t ParallelScavengeHeap::permanent_capacity() const { - return perm_gen()->capacity_in_bytes(); -} - -size_t ParallelScavengeHeap::permanent_used() const { - return perm_gen()->used_in_bytes(); -} - size_t ParallelScavengeHeap::max_capacity() const { size_t estimated = reserved_region().byte_size(); - estimated -= perm_gen()->reserved().byte_size(); if (UseAdaptiveSizePolicy) { estimated -= _size_policy->max_survivor_size(young_gen()->max_size()); } else { @@ -319,10 +250,6 @@ return true; } - if (perm_gen()->is_in(p)) { - return true; - } - return false; } @@ -335,10 +262,6 @@ return true; } - if (perm_gen()->is_in_reserved(p)) { - return true; - } - return false; } @@ -352,7 +275,7 @@ bool ParallelScavengeHeap::is_in_partial_collection(const void *p) { assert(is_in_reserved(p) || p == NULL, "Does not work if address is non-null and outside of the heap"); - // The order of the generations is perm (low addr), old, young (high addr) + // The order of the generations is old (low addr), young (high addr) return p >= old_gen()->reserved().end(); } #endif @@ -553,6 +476,18 @@ return NULL; } +void ParallelScavengeHeap::do_full_collection(bool clear_all_soft_refs) { + if (UseParallelOldGC) { + // The do_full_collection() parameter clear_all_soft_refs + // is interpreted here as maximum_compaction which will + // cause SoftRefs to be cleared. + bool maximum_compaction = clear_all_soft_refs; + PSParallelCompact::invoke(maximum_compaction); + } else { + PSMarkSweep::invoke(clear_all_soft_refs); + } +} + // Failed allocation policy. Must be called from the VM thread, and // only at a safepoint! Note that this method has policy for allocation // flow, and NOT collection policy. So we do not check for gc collection @@ -575,7 +510,7 @@ // Second level allocation failure. // Mark sweep and allocate in young generation. if (result == NULL && !invoked_full_gc) { - invoke_full_gc(false); + do_full_collection(false); result = young_gen()->allocate(size); } @@ -591,7 +526,7 @@ // Fourth level allocation failure. We're running out of memory. // More complete mark sweep and allocate in young generation. if (result == NULL) { - invoke_full_gc(true); + do_full_collection(true); result = young_gen()->allocate(size); } @@ -604,160 +539,6 @@ return result; } -// -// This is the policy loop for allocating in the permanent generation. -// If the initial allocation fails, we create a vm operation which will -// cause a collection. -HeapWord* ParallelScavengeHeap::permanent_mem_allocate(size_t size) { - assert(!SafepointSynchronize::is_at_safepoint(), "should not be at safepoint"); - assert(Thread::current() != (Thread*)VMThread::vm_thread(), "should not be in vm thread"); - assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); - - HeapWord* result; - - uint loop_count = 0; - uint gc_count = 0; - uint full_gc_count = 0; - - do { - // We don't want to have multiple collections for a single filled generation. - // To prevent this, each thread tracks the total_collections() value, and if - // the count has changed, does not do a new collection. - // - // The collection count must be read only while holding the heap lock. VM - // operations also hold the heap lock during collections. There is a lock - // contention case where thread A blocks waiting on the Heap_lock, while - // thread B is holding it doing a collection. When thread A gets the lock, - // the collection count has already changed. To prevent duplicate collections, - // The policy MUST attempt allocations during the same period it reads the - // total_collections() value! - { - MutexLocker ml(Heap_lock); - gc_count = Universe::heap()->total_collections(); - full_gc_count = Universe::heap()->total_full_collections(); - - result = perm_gen()->allocate_permanent(size); - - if (result != NULL) { - return result; - } - - if (GC_locker::is_active_and_needs_gc()) { - // If this thread is not in a jni critical section, we stall - // the requestor until the critical section has cleared and - // GC allowed. When the critical section clears, a GC is - // initiated by the last thread exiting the critical section; so - // we retry the allocation sequence from the beginning of the loop, - // rather than causing more, now probably unnecessary, GC attempts. - JavaThread* jthr = JavaThread::current(); - if (!jthr->in_critical()) { - MutexUnlocker mul(Heap_lock); - GC_locker::stall_until_clear(); - continue; - } else { - if (CheckJNICalls) { - fatal("Possible deadlock due to allocating while" - " in jni critical section"); - } - return NULL; - } - } - } - - if (result == NULL) { - - // Exit the loop if the gc time limit has been exceeded. - // The allocation must have failed above (result must be NULL), - // and the most recent collection must have exceeded the - // gc time limit. Exit the loop so that an out-of-memory - // will be thrown (returning a NULL will do that), but - // clear gc_overhead_limit_exceeded so that the next collection - // will succeeded if the applications decides to handle the - // out-of-memory and tries to go on. - const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded(); - if (limit_exceeded) { - size_policy()->set_gc_overhead_limit_exceeded(false); - if (PrintGCDetails && Verbose) { - gclog_or_tty->print_cr("ParallelScavengeHeap::permanent_mem_allocate:" - " return NULL because gc_overhead_limit_exceeded is set"); - } - assert(result == NULL, "Allocation did not fail"); - return NULL; - } - - // Generate a VM operation - VM_ParallelGCFailedPermanentAllocation op(size, gc_count, full_gc_count); - VMThread::execute(&op); - - // Did the VM operation execute? If so, return the result directly. - // This prevents us from looping until time out on requests that can - // not be satisfied. - if (op.prologue_succeeded()) { - assert(Universe::heap()->is_in_permanent_or_null(op.result()), - "result not in heap"); - // If GC was locked out during VM operation then retry allocation - // and/or stall as necessary. - if (op.gc_locked()) { - assert(op.result() == NULL, "must be NULL if gc_locked() is true"); - continue; // retry and/or stall as necessary - } - // If a NULL results is being returned, an out-of-memory - // will be thrown now. Clear the gc_overhead_limit_exceeded - // flag to avoid the following situation. - // gc_overhead_limit_exceeded is set during a collection - // the collection fails to return enough space and an OOM is thrown - // a subsequent GC prematurely throws an out-of-memory because - // the gc_overhead_limit_exceeded counts did not start - // again from 0. - if (op.result() == NULL) { - size_policy()->reset_gc_overhead_limit_count(); - } - return op.result(); - } - } - - // The policy object will prevent us from looping forever. If the - // time spent in gc crosses a threshold, we will bail out. - loop_count++; - if ((QueuedAllocationWarningCount > 0) && - (loop_count % QueuedAllocationWarningCount == 0)) { - warning("ParallelScavengeHeap::permanent_mem_allocate retries %d times \n\t" - " size=%d", loop_count, size); - } - } while (result == NULL); - - return result; -} - -// -// This is the policy code for permanent allocations which have failed -// and require a collection. Note that just as in failed_mem_allocate, -// we do not set collection policy, only where & when to allocate and -// collect. -HeapWord* ParallelScavengeHeap::failed_permanent_mem_allocate(size_t size) { - assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); - assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); - assert(!Universe::heap()->is_gc_active(), "not reentrant"); - assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); - assert(size > perm_gen()->free_in_words(), "Allocation should fail"); - - // We assume (and assert!) that an allocation at this point will fail - // unless we collect. - - // First level allocation failure. Mark-sweep and allocate in perm gen. - GCCauseSetter gccs(this, GCCause::_allocation_failure); - invoke_full_gc(false); - HeapWord* result = perm_gen()->allocate_permanent(size); - - // Second level allocation failure. We're running out of memory. - if (result == NULL) { - invoke_full_gc(true); - result = perm_gen()->allocate_permanent(size); - } - - return result; -} - void ParallelScavengeHeap::ensure_parsability(bool retire_tlabs) { CollectedHeap::ensure_parsability(retire_tlabs); young_gen()->eden_space()->ensure_parsability(); @@ -812,44 +593,15 @@ VMThread::execute(&op); } -// This interface assumes that it's being called by the -// vm thread. It collects the heap assuming that the -// heap lock is already held and that we are executing in -// the context of the vm thread. -void ParallelScavengeHeap::collect_as_vm_thread(GCCause::Cause cause) { - assert(Thread::current()->is_VM_thread(), "Precondition#1"); - assert(Heap_lock->is_locked(), "Precondition#2"); - GCCauseSetter gcs(this, cause); - switch (cause) { - case GCCause::_heap_inspection: - case GCCause::_heap_dump: { - HandleMark hm; - invoke_full_gc(false); - break; - } - default: // XXX FIX ME - ShouldNotReachHere(); - } -} - - -void ParallelScavengeHeap::oop_iterate(OopClosure* cl) { +void ParallelScavengeHeap::oop_iterate(ExtendedOopClosure* cl) { Unimplemented(); } void ParallelScavengeHeap::object_iterate(ObjectClosure* cl) { young_gen()->object_iterate(cl); old_gen()->object_iterate(cl); - perm_gen()->object_iterate(cl); } -void ParallelScavengeHeap::permanent_oop_iterate(OopClosure* cl) { - Unimplemented(); -} - -void ParallelScavengeHeap::permanent_object_iterate(ObjectClosure* cl) { - perm_gen()->object_iterate(cl); -} HeapWord* ParallelScavengeHeap::block_start(const void* addr) const { if (young_gen()->is_in_reserved(addr)) { @@ -862,10 +614,6 @@ assert(old_gen()->is_in(addr), "addr should be in allocated part of old gen"); return old_gen()->start_array()->object_start((HeapWord*)addr); - } else if (perm_gen()->is_in_reserved(addr)) { - assert(perm_gen()->is_in(addr), - "addr should be in allocated part of perm gen"); - return perm_gen()->start_array()->object_start((HeapWord*)addr); } return 0; } @@ -891,7 +639,7 @@ void ParallelScavengeHeap::print_on(outputStream* st) const { young_gen()->print_on(st); old_gen()->print_on(st); - perm_gen()->print_on(st); + MetaspaceAux::print_on(st); } void ParallelScavengeHeap::gc_threads_do(ThreadClosure* tc) const { @@ -918,11 +666,6 @@ // Why do we need the total_collections()-filter below? if (total_collections() > 0) { if (!silent) { - gclog_or_tty->print("permanent "); - } - perm_gen()->verify(); - - if (!silent) { gclog_or_tty->print("tenured "); } old_gen()->verify(); @@ -1000,7 +743,6 @@ if (ZapUnusedHeapArea) { young_gen()->record_spaces_top(); old_gen()->record_spaces_top(); - perm_gen()->record_spaces_top(); } } @@ -1010,7 +752,6 @@ young_gen()->to_space()->mangle_unused_area(); young_gen()->from_space()->mangle_unused_area(); old_gen()->object_space()->mangle_unused_area(); - perm_gen()->object_space()->mangle_unused_area(); } } #endif