Mercurial > hg > graal-jvmci-8
view src/share/vm/services/heapDumper.cpp @ 1145:e018e6884bd8
6631166: CMS: better heuristics when combatting fragmentation
Summary: Autonomic per-worker free block cache sizing, tunable coalition policies, fixes to per-size block statistics, retuned gain and bandwidth of some feedback loop filters to allow quicker reactivity to abrupt changes in ambient demand, and other heuristics to reduce fragmentation of the CMS old gen. Also tightened some assertions, including those related to locking.
Reviewed-by: jmasa
author | ysr |
---|---|
date | Wed, 23 Dec 2009 09:23:54 -0800 |
parents | 72a6752ac432 |
children | 4ce7240d622c |
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/* * Copyright 2005-2009 Sun Microsystems, Inc. All Rights Reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, * CA 95054 USA or visit www.sun.com if you need additional information or * have any questions. * */ # include "incls/_precompiled.incl" # include "incls/_heapDumper.cpp.incl" /* * HPROF binary format - description copied from: * src/share/demo/jvmti/hprof/hprof_io.c * * * header "JAVA PROFILE 1.0.1" or "JAVA PROFILE 1.0.2" * (0-terminated) * * u4 size of identifiers. Identifiers are used to represent * UTF8 strings, objects, stack traces, etc. They usually * have the same size as host pointers. For example, on * Solaris and Win32, the size is 4. * u4 high word * u4 low word number of milliseconds since 0:00 GMT, 1/1/70 * [record]* a sequence of records. * * * Record format: * * u1 a TAG denoting the type of the record * u4 number of *microseconds* since the time stamp in the * header. (wraps around in a little more than an hour) * u4 number of bytes *remaining* in the record. Note that * this number excludes the tag and the length field itself. * [u1]* BODY of the record (a sequence of bytes) * * * The following TAGs are supported: * * TAG BODY notes *---------------------------------------------------------- * HPROF_UTF8 a UTF8-encoded name * * id name ID * [u1]* UTF8 characters (no trailing zero) * * HPROF_LOAD_CLASS a newly loaded class * * u4 class serial number (> 0) * id class object ID * u4 stack trace serial number * id class name ID * * HPROF_UNLOAD_CLASS an unloading class * * u4 class serial_number * * HPROF_FRAME a Java stack frame * * id stack frame ID * id method name ID * id method signature ID * id source file name ID * u4 class serial number * i4 line number. >0: normal * -1: unknown * -2: compiled method * -3: native method * * HPROF_TRACE a Java stack trace * * u4 stack trace serial number * u4 thread serial number * u4 number of frames * [id]* stack frame IDs * * * HPROF_ALLOC_SITES a set of heap allocation sites, obtained after GC * * u2 flags 0x0001: incremental vs. complete * 0x0002: sorted by allocation vs. live * 0x0004: whether to force a GC * u4 cutoff ratio * u4 total live bytes * u4 total live instances * u8 total bytes allocated * u8 total instances allocated * u4 number of sites that follow * [u1 is_array: 0: normal object * 2: object array * 4: boolean array * 5: char array * 6: float array * 7: double array * 8: byte array * 9: short array * 10: int array * 11: long array * u4 class serial number (may be zero during startup) * u4 stack trace serial number * u4 number of bytes alive * u4 number of instances alive * u4 number of bytes allocated * u4]* number of instance allocated * * HPROF_START_THREAD a newly started thread. * * u4 thread serial number (> 0) * id thread object ID * u4 stack trace serial number * id thread name ID * id thread group name ID * id thread group parent name ID * * HPROF_END_THREAD a terminating thread. * * u4 thread serial number * * HPROF_HEAP_SUMMARY heap summary * * u4 total live bytes * u4 total live instances * u8 total bytes allocated * u8 total instances allocated * * HPROF_HEAP_DUMP denote a heap dump * * [heap dump sub-records]* * * There are four kinds of heap dump sub-records: * * u1 sub-record type * * HPROF_GC_ROOT_UNKNOWN unknown root * * id object ID * * HPROF_GC_ROOT_THREAD_OBJ thread object * * id thread object ID (may be 0 for a * thread newly attached through JNI) * u4 thread sequence number * u4 stack trace sequence number * * HPROF_GC_ROOT_JNI_GLOBAL JNI global ref root * * id object ID * id JNI global ref ID * * HPROF_GC_ROOT_JNI_LOCAL JNI local ref * * id object ID * u4 thread serial number * u4 frame # in stack trace (-1 for empty) * * HPROF_GC_ROOT_JAVA_FRAME Java stack frame * * id object ID * u4 thread serial number * u4 frame # in stack trace (-1 for empty) * * HPROF_GC_ROOT_NATIVE_STACK Native stack * * id object ID * u4 thread serial number * * HPROF_GC_ROOT_STICKY_CLASS System class * * id object ID * * HPROF_GC_ROOT_THREAD_BLOCK Reference from thread block * * id object ID * u4 thread serial number * * HPROF_GC_ROOT_MONITOR_USED Busy monitor * * id object ID * * HPROF_GC_CLASS_DUMP dump of a class object * * id class object ID * u4 stack trace serial number * id super class object ID * id class loader object ID * id signers object ID * id protection domain object ID * id reserved * id reserved * * u4 instance size (in bytes) * * u2 size of constant pool * [u2, constant pool index, * ty, type * 2: object * 4: boolean * 5: char * 6: float * 7: double * 8: byte * 9: short * 10: int * 11: long * vl]* and value * * u2 number of static fields * [id, static field name, * ty, type, * vl]* and value * * u2 number of inst. fields (not inc. super) * [id, instance field name, * ty]* type * * HPROF_GC_INSTANCE_DUMP dump of a normal object * * id object ID * u4 stack trace serial number * id class object ID * u4 number of bytes that follow * [vl]* instance field values (class, followed * by super, super's super ...) * * HPROF_GC_OBJ_ARRAY_DUMP dump of an object array * * id array object ID * u4 stack trace serial number * u4 number of elements * id array class ID * [id]* elements * * HPROF_GC_PRIM_ARRAY_DUMP dump of a primitive array * * id array object ID * u4 stack trace serial number * u4 number of elements * u1 element type * 4: boolean array * 5: char array * 6: float array * 7: double array * 8: byte array * 9: short array * 10: int array * 11: long array * [u1]* elements * * HPROF_CPU_SAMPLES a set of sample traces of running threads * * u4 total number of samples * u4 # of traces * [u4 # of samples * u4]* stack trace serial number * * HPROF_CONTROL_SETTINGS the settings of on/off switches * * u4 0x00000001: alloc traces on/off * 0x00000002: cpu sampling on/off * u2 stack trace depth * * * When the header is "JAVA PROFILE 1.0.2" a heap dump can optionally * be generated as a sequence of heap dump segments. This sequence is * terminated by an end record. The additional tags allowed by format * "JAVA PROFILE 1.0.2" are: * * HPROF_HEAP_DUMP_SEGMENT denote a heap dump segment * * [heap dump sub-records]* * The same sub-record types allowed by HPROF_HEAP_DUMP * * HPROF_HEAP_DUMP_END denotes the end of a heap dump * */ // HPROF tags typedef enum { // top-level records HPROF_UTF8 = 0x01, HPROF_LOAD_CLASS = 0x02, HPROF_UNLOAD_CLASS = 0x03, HPROF_FRAME = 0x04, HPROF_TRACE = 0x05, HPROF_ALLOC_SITES = 0x06, HPROF_HEAP_SUMMARY = 0x07, HPROF_START_THREAD = 0x0A, HPROF_END_THREAD = 0x0B, HPROF_HEAP_DUMP = 0x0C, HPROF_CPU_SAMPLES = 0x0D, HPROF_CONTROL_SETTINGS = 0x0E, // 1.0.2 record types HPROF_HEAP_DUMP_SEGMENT = 0x1C, HPROF_HEAP_DUMP_END = 0x2C, // field types HPROF_ARRAY_OBJECT = 0x01, HPROF_NORMAL_OBJECT = 0x02, HPROF_BOOLEAN = 0x04, HPROF_CHAR = 0x05, HPROF_FLOAT = 0x06, HPROF_DOUBLE = 0x07, HPROF_BYTE = 0x08, HPROF_SHORT = 0x09, HPROF_INT = 0x0A, HPROF_LONG = 0x0B, // data-dump sub-records HPROF_GC_ROOT_UNKNOWN = 0xFF, HPROF_GC_ROOT_JNI_GLOBAL = 0x01, HPROF_GC_ROOT_JNI_LOCAL = 0x02, HPROF_GC_ROOT_JAVA_FRAME = 0x03, HPROF_GC_ROOT_NATIVE_STACK = 0x04, HPROF_GC_ROOT_STICKY_CLASS = 0x05, HPROF_GC_ROOT_THREAD_BLOCK = 0x06, HPROF_GC_ROOT_MONITOR_USED = 0x07, HPROF_GC_ROOT_THREAD_OBJ = 0x08, HPROF_GC_CLASS_DUMP = 0x20, HPROF_GC_INSTANCE_DUMP = 0x21, HPROF_GC_OBJ_ARRAY_DUMP = 0x22, HPROF_GC_PRIM_ARRAY_DUMP = 0x23 } hprofTag; // Default stack trace ID (used for dummy HPROF_TRACE record) enum { STACK_TRACE_ID = 1, INITIAL_CLASS_COUNT = 200 }; // Supports I/O operations on a dump file class DumpWriter : public StackObj { private: enum { io_buffer_size = 8*M }; int _fd; // file descriptor (-1 if dump file not open) jlong _bytes_written; // number of byte written to dump file char* _buffer; // internal buffer int _size; int _pos; char* _error; // error message when I/O fails void set_file_descriptor(int fd) { _fd = fd; } int file_descriptor() const { return _fd; } char* buffer() const { return _buffer; } int buffer_size() const { return _size; } int position() const { return _pos; } void set_position(int pos) { _pos = pos; } void set_error(const char* error) { _error = (char*)os::strdup(error); } // all I/O go through this function void write_internal(void* s, int len); public: DumpWriter(const char* path); ~DumpWriter(); void close(); bool is_open() const { return file_descriptor() >= 0; } void flush(); // total number of bytes written to the disk jlong bytes_written() const { return _bytes_written; } // adjust the number of bytes written to disk (used to keep the count // of the number of bytes written in case of rewrites) void adjust_bytes_written(jlong n) { _bytes_written += n; } // number of (buffered) bytes as yet unwritten to the dump file jlong bytes_unwritten() const { return (jlong)position(); } char* error() const { return _error; } jlong current_offset(); void seek_to_offset(jlong pos); // writer functions void write_raw(void* s, int len); void write_u1(u1 x) { write_raw((void*)&x, 1); } void write_u2(u2 x); void write_u4(u4 x); void write_u8(u8 x); void write_objectID(oop o); void write_classID(Klass* k); void write_id(u4 x); }; DumpWriter::DumpWriter(const char* path) { // try to allocate an I/O buffer of io_buffer_size. If there isn't // sufficient memory then reduce size until we can allocate something. _size = io_buffer_size; do { _buffer = (char*)os::malloc(_size); if (_buffer == NULL) { _size = _size >> 1; } } while (_buffer == NULL && _size > 0); assert((_size > 0 && _buffer != NULL) || (_size == 0 && _buffer == NULL), "sanity check"); _pos = 0; _error = NULL; _bytes_written = 0L; _fd = os::create_binary_file(path, false); // don't replace existing file // if the open failed we record the error if (_fd < 0) { _error = (char*)os::strdup(strerror(errno)); } } DumpWriter::~DumpWriter() { // flush and close dump file if (file_descriptor() >= 0) { close(); } if (_buffer != NULL) os::free(_buffer); if (_error != NULL) os::free(_error); } // closes dump file (if open) void DumpWriter::close() { // flush and close dump file if (file_descriptor() >= 0) { flush(); ::close(file_descriptor()); } } // write directly to the file void DumpWriter::write_internal(void* s, int len) { if (is_open()) { int n = ::write(file_descriptor(), s, len); if (n > 0) { _bytes_written += n; } if (n != len) { if (n < 0) { set_error(strerror(errno)); } else { set_error("file size limit"); } ::close(file_descriptor()); set_file_descriptor(-1); } } } // write raw bytes void DumpWriter::write_raw(void* s, int len) { if (is_open()) { // flush buffer to make toom if ((position()+ len) >= buffer_size()) { flush(); } // buffer not available or too big to buffer it if ((buffer() == NULL) || (len >= buffer_size())) { write_internal(s, len); } else { // Should optimize this for u1/u2/u4/u8 sizes. memcpy(buffer() + position(), s, len); set_position(position() + len); } } } // flush any buffered bytes to the file void DumpWriter::flush() { if (is_open() && position() > 0) { write_internal(buffer(), position()); set_position(0); } } jlong DumpWriter::current_offset() { if (is_open()) { // the offset is the file offset plus whatever we have buffered jlong offset = os::current_file_offset(file_descriptor()); assert(offset >= 0, "lseek failed"); return offset + (jlong)position(); } else { return (jlong)-1; } } void DumpWriter::seek_to_offset(jlong off) { assert(off >= 0, "bad offset"); // need to flush before seeking flush(); // may be closed due to I/O error if (is_open()) { jlong n = os::seek_to_file_offset(file_descriptor(), off); assert(n >= 0, "lseek failed"); } } void DumpWriter::write_u2(u2 x) { u2 v; Bytes::put_Java_u2((address)&v, x); write_raw((void*)&v, 2); } void DumpWriter::write_u4(u4 x) { u4 v; Bytes::put_Java_u4((address)&v, x); write_raw((void*)&v, 4); } void DumpWriter::write_u8(u8 x) { u8 v; Bytes::put_Java_u8((address)&v, x); write_raw((void*)&v, 8); } void DumpWriter::write_objectID(oop o) { address a = (address)((uintptr_t)o); #ifdef _LP64 write_u8((u8)a); #else write_u4((u4)a); #endif } void DumpWriter::write_id(u4 x) { #ifdef _LP64 write_u8((u8) x); #else write_u4(x); #endif } // We use java mirror as the class ID void DumpWriter::write_classID(Klass* k) { write_objectID(k->java_mirror()); } // Support class with a collection of functions used when dumping the heap class DumperSupport : AllStatic { public: // write a header of the given type static void write_header(DumpWriter* writer, hprofTag tag, u4 len); // returns hprof tag for the given type signature static hprofTag sig2tag(symbolOop sig); // returns hprof tag for the given basic type static hprofTag type2tag(BasicType type); // returns the size of the instance of the given class static u4 instance_size(klassOop k); // dump a jfloat static void dump_float(DumpWriter* writer, jfloat f); // dump a jdouble static void dump_double(DumpWriter* writer, jdouble d); // dumps the raw value of the given field static void dump_field_value(DumpWriter* writer, char type, address addr); // dumps static fields of the given class static void dump_static_fields(DumpWriter* writer, klassOop k); // dump the raw values of the instance fields of the given object static void dump_instance_fields(DumpWriter* writer, oop o); // dumps the definition of the instance fields for a given class static void dump_instance_field_descriptors(DumpWriter* writer, klassOop k); // creates HPROF_GC_INSTANCE_DUMP record for the given object static void dump_instance(DumpWriter* writer, oop o); // creates HPROF_GC_CLASS_DUMP record for the given class and each of its // array classes static void dump_class_and_array_classes(DumpWriter* writer, klassOop k); // creates HPROF_GC_CLASS_DUMP record for a given primitive array // class (and each multi-dimensional array class too) static void dump_basic_type_array_class(DumpWriter* writer, klassOop k); // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array static void dump_object_array(DumpWriter* writer, objArrayOop array); // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array static void dump_prim_array(DumpWriter* writer, typeArrayOop array); // create HPROF_FRAME record for the given method and bci static void dump_stack_frame(DumpWriter* writer, int frame_serial_num, int class_serial_num, methodOop m, int bci); }; // write a header of the given type void DumperSupport:: write_header(DumpWriter* writer, hprofTag tag, u4 len) { writer->write_u1((u1)tag); writer->write_u4(0); // current ticks writer->write_u4(len); } // returns hprof tag for the given type signature hprofTag DumperSupport::sig2tag(symbolOop sig) { switch (sig->byte_at(0)) { case JVM_SIGNATURE_CLASS : return HPROF_NORMAL_OBJECT; case JVM_SIGNATURE_ARRAY : return HPROF_NORMAL_OBJECT; case JVM_SIGNATURE_BYTE : return HPROF_BYTE; case JVM_SIGNATURE_CHAR : return HPROF_CHAR; case JVM_SIGNATURE_FLOAT : return HPROF_FLOAT; case JVM_SIGNATURE_DOUBLE : return HPROF_DOUBLE; case JVM_SIGNATURE_INT : return HPROF_INT; case JVM_SIGNATURE_LONG : return HPROF_LONG; case JVM_SIGNATURE_SHORT : return HPROF_SHORT; case JVM_SIGNATURE_BOOLEAN : return HPROF_BOOLEAN; default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE; } } hprofTag DumperSupport::type2tag(BasicType type) { switch (type) { case T_BYTE : return HPROF_BYTE; case T_CHAR : return HPROF_CHAR; case T_FLOAT : return HPROF_FLOAT; case T_DOUBLE : return HPROF_DOUBLE; case T_INT : return HPROF_INT; case T_LONG : return HPROF_LONG; case T_SHORT : return HPROF_SHORT; case T_BOOLEAN : return HPROF_BOOLEAN; default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE; } } // dump a jfloat void DumperSupport::dump_float(DumpWriter* writer, jfloat f) { if (g_isnan(f)) { writer->write_u4(0x7fc00000); // collapsing NaNs } else { union { int i; float f; } u; u.f = (float)f; writer->write_u4((u4)u.i); } } // dump a jdouble void DumperSupport::dump_double(DumpWriter* writer, jdouble d) { union { jlong l; double d; } u; if (g_isnan(d)) { // collapsing NaNs u.l = (jlong)(0x7ff80000); u.l = (u.l << 32); } else { u.d = (double)d; } writer->write_u8((u8)u.l); } // dumps the raw value of the given field void DumperSupport::dump_field_value(DumpWriter* writer, char type, address addr) { switch (type) { case JVM_SIGNATURE_CLASS : case JVM_SIGNATURE_ARRAY : { oop o; if (UseCompressedOops) { o = oopDesc::load_decode_heap_oop((narrowOop*)addr); } else { o = oopDesc::load_decode_heap_oop((oop*)addr); } // reflection and sun.misc.Unsafe classes may have a reference to a // klassOop so filter it out. if (o != NULL && o->is_klass()) { o = NULL; } // FIXME: When sharing is enabled we don't emit field references to objects // in shared spaces. We can remove this once we write records for the classes // and strings that are shared. if (o != NULL && o->is_shared()) { o = NULL; } writer->write_objectID(o); break; } case JVM_SIGNATURE_BYTE : { jbyte* b = (jbyte*)addr; writer->write_u1((u1)*b); break; } case JVM_SIGNATURE_CHAR : { jchar* c = (jchar*)addr; writer->write_u2((u2)*c); break; } case JVM_SIGNATURE_SHORT : { jshort* s = (jshort*)addr; writer->write_u2((u2)*s); break; } case JVM_SIGNATURE_FLOAT : { jfloat* f = (jfloat*)addr; dump_float(writer, *f); break; } case JVM_SIGNATURE_DOUBLE : { jdouble* f = (jdouble*)addr; dump_double(writer, *f); break; } case JVM_SIGNATURE_INT : { jint* i = (jint*)addr; writer->write_u4((u4)*i); break; } case JVM_SIGNATURE_LONG : { jlong* l = (jlong*)addr; writer->write_u8((u8)*l); break; } case JVM_SIGNATURE_BOOLEAN : { jboolean* b = (jboolean*)addr; writer->write_u1((u1)*b); break; } default : ShouldNotReachHere(); } } // returns the size of the instance of the given class u4 DumperSupport::instance_size(klassOop k) { HandleMark hm; instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k); int size = 0; for (FieldStream fld(ikh, false, false); !fld.eos(); fld.next()) { if (!fld.access_flags().is_static()) { symbolOop sig = fld.signature(); switch (sig->byte_at(0)) { case JVM_SIGNATURE_CLASS : case JVM_SIGNATURE_ARRAY : size += oopSize; break; case JVM_SIGNATURE_BYTE : case JVM_SIGNATURE_BOOLEAN : size += 1; break; case JVM_SIGNATURE_CHAR : case JVM_SIGNATURE_SHORT : size += 2; break; case JVM_SIGNATURE_INT : case JVM_SIGNATURE_FLOAT : size += 4; break; case JVM_SIGNATURE_LONG : case JVM_SIGNATURE_DOUBLE : size += 8; break; default : ShouldNotReachHere(); } } } return (u4)size; } // dumps static fields of the given class void DumperSupport::dump_static_fields(DumpWriter* writer, klassOop k) { HandleMark hm; instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k); // pass 1 - count the static fields u2 field_count = 0; for (FieldStream fldc(ikh, true, true); !fldc.eos(); fldc.next()) { if (fldc.access_flags().is_static()) field_count++; } writer->write_u2(field_count); // pass 2 - dump the field descriptors and raw values for (FieldStream fld(ikh, true, true); !fld.eos(); fld.next()) { if (fld.access_flags().is_static()) { symbolOop sig = fld.signature(); writer->write_objectID(fld.name()); // name writer->write_u1(sig2tag(sig)); // type // value int offset = fld.offset(); address addr = (address)k + offset; dump_field_value(writer, sig->byte_at(0), addr); } } } // dump the raw values of the instance fields of the given object void DumperSupport::dump_instance_fields(DumpWriter* writer, oop o) { HandleMark hm; instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), o->klass()); for (FieldStream fld(ikh, false, false); !fld.eos(); fld.next()) { if (!fld.access_flags().is_static()) { symbolOop sig = fld.signature(); address addr = (address)o + fld.offset(); dump_field_value(writer, sig->byte_at(0), addr); } } } // dumps the definition of the instance fields for a given class void DumperSupport::dump_instance_field_descriptors(DumpWriter* writer, klassOop k) { HandleMark hm; instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k); // pass 1 - count the instance fields u2 field_count = 0; for (FieldStream fldc(ikh, true, true); !fldc.eos(); fldc.next()) { if (!fldc.access_flags().is_static()) field_count++; } writer->write_u2(field_count); // pass 2 - dump the field descriptors for (FieldStream fld(ikh, true, true); !fld.eos(); fld.next()) { if (!fld.access_flags().is_static()) { symbolOop sig = fld.signature(); writer->write_objectID(fld.name()); // name writer->write_u1(sig2tag(sig)); // type } } } // creates HPROF_GC_INSTANCE_DUMP record for the given object void DumperSupport::dump_instance(DumpWriter* writer, oop o) { klassOop k = o->klass(); writer->write_u1(HPROF_GC_INSTANCE_DUMP); writer->write_objectID(o); writer->write_u4(STACK_TRACE_ID); // class ID writer->write_classID(Klass::cast(k)); // number of bytes that follow writer->write_u4(instance_size(k) ); // field values dump_instance_fields(writer, o); } // creates HPROF_GC_CLASS_DUMP record for the given class and each of // its array classes void DumperSupport::dump_class_and_array_classes(DumpWriter* writer, klassOop k) { Klass* klass = Klass::cast(k); assert(klass->oop_is_instance(), "not an instanceKlass"); instanceKlass* ik = (instanceKlass*)klass; writer->write_u1(HPROF_GC_CLASS_DUMP); // class ID writer->write_classID(ik); writer->write_u4(STACK_TRACE_ID); // super class ID klassOop java_super = ik->java_super(); if (java_super == NULL) { writer->write_objectID(NULL); } else { writer->write_classID(Klass::cast(java_super)); } writer->write_objectID(ik->class_loader()); writer->write_objectID(ik->signers()); writer->write_objectID(ik->protection_domain()); // reserved writer->write_objectID(NULL); writer->write_objectID(NULL); // instance size writer->write_u4(DumperSupport::instance_size(k)); // size of constant pool - ignored by HAT 1.1 writer->write_u2(0); // number of static fields dump_static_fields(writer, k); // description of instance fields dump_instance_field_descriptors(writer, k); // array classes k = klass->array_klass_or_null(); while (k != NULL) { Klass* klass = Klass::cast(k); assert(klass->oop_is_objArray(), "not an objArrayKlass"); writer->write_u1(HPROF_GC_CLASS_DUMP); writer->write_classID(klass); writer->write_u4(STACK_TRACE_ID); // super class of array classes is java.lang.Object java_super = klass->java_super(); assert(java_super != NULL, "checking"); writer->write_classID(Klass::cast(java_super)); writer->write_objectID(ik->class_loader()); writer->write_objectID(ik->signers()); writer->write_objectID(ik->protection_domain()); writer->write_objectID(NULL); // reserved writer->write_objectID(NULL); writer->write_u4(0); // instance size writer->write_u2(0); // constant pool writer->write_u2(0); // static fields writer->write_u2(0); // instance fields // get the array class for the next rank k = klass->array_klass_or_null(); } } // creates HPROF_GC_CLASS_DUMP record for a given primitive array // class (and each multi-dimensional array class too) void DumperSupport::dump_basic_type_array_class(DumpWriter* writer, klassOop k) { // array classes while (k != NULL) { Klass* klass = Klass::cast(k); writer->write_u1(HPROF_GC_CLASS_DUMP); writer->write_classID(klass); writer->write_u4(STACK_TRACE_ID); // super class of array classes is java.lang.Object klassOop java_super = klass->java_super(); assert(java_super != NULL, "checking"); writer->write_classID(Klass::cast(java_super)); writer->write_objectID(NULL); // loader writer->write_objectID(NULL); // signers writer->write_objectID(NULL); // protection domain writer->write_objectID(NULL); // reserved writer->write_objectID(NULL); writer->write_u4(0); // instance size writer->write_u2(0); // constant pool writer->write_u2(0); // static fields writer->write_u2(0); // instance fields // get the array class for the next rank k = klass->array_klass_or_null(); } } // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array void DumperSupport::dump_object_array(DumpWriter* writer, objArrayOop array) { // filter this if (array->klass() == Universe::systemObjArrayKlassObj()) return; writer->write_u1(HPROF_GC_OBJ_ARRAY_DUMP); writer->write_objectID(array); writer->write_u4(STACK_TRACE_ID); writer->write_u4((u4)array->length()); // array class ID writer->write_classID(Klass::cast(array->klass())); // [id]* elements for (int index=0; index<array->length(); index++) { oop o = array->obj_at(index); writer->write_objectID(o); } } #define WRITE_ARRAY(Array, Type, Size) \ for (int i=0; i<Array->length(); i++) { writer->write_##Size((Size)array->Type##_at(i)); } // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array void DumperSupport::dump_prim_array(DumpWriter* writer, typeArrayOop array) { BasicType type = typeArrayKlass::cast(array->klass())->element_type(); writer->write_u1(HPROF_GC_PRIM_ARRAY_DUMP); writer->write_objectID(array); writer->write_u4(STACK_TRACE_ID); writer->write_u4((u4)array->length()); writer->write_u1(type2tag(type)); // nothing to copy if (array->length() == 0) { return; } // If the byte ordering is big endian then we can copy most types directly int length_in_bytes = array->length() * type2aelembytes(type); assert(length_in_bytes > 0, "nothing to copy"); switch (type) { case T_INT : { if (Bytes::is_Java_byte_ordering_different()) { WRITE_ARRAY(array, int, u4); } else { writer->write_raw((void*)(array->int_at_addr(0)), length_in_bytes); } break; } case T_BYTE : { writer->write_raw((void*)(array->byte_at_addr(0)), length_in_bytes); break; } case T_CHAR : { if (Bytes::is_Java_byte_ordering_different()) { WRITE_ARRAY(array, char, u2); } else { writer->write_raw((void*)(array->char_at_addr(0)), length_in_bytes); } break; } case T_SHORT : { if (Bytes::is_Java_byte_ordering_different()) { WRITE_ARRAY(array, short, u2); } else { writer->write_raw((void*)(array->short_at_addr(0)), length_in_bytes); } break; } case T_BOOLEAN : { if (Bytes::is_Java_byte_ordering_different()) { WRITE_ARRAY(array, bool, u1); } else { writer->write_raw((void*)(array->bool_at_addr(0)), length_in_bytes); } break; } case T_LONG : { if (Bytes::is_Java_byte_ordering_different()) { WRITE_ARRAY(array, long, u8); } else { writer->write_raw((void*)(array->long_at_addr(0)), length_in_bytes); } break; } // handle float/doubles in a special value to ensure than NaNs are // written correctly. TO DO: Check if we can avoid this on processors that // use IEEE 754. case T_FLOAT : { for (int i=0; i<array->length(); i++) { dump_float( writer, array->float_at(i) ); } break; } case T_DOUBLE : { for (int i=0; i<array->length(); i++) { dump_double( writer, array->double_at(i) ); } break; } default : ShouldNotReachHere(); } } // create a HPROF_FRAME record of the given methodOop and bci void DumperSupport::dump_stack_frame(DumpWriter* writer, int frame_serial_num, int class_serial_num, methodOop m, int bci) { int line_number; if (m->is_native()) { line_number = -3; // native frame } else { line_number = m->line_number_from_bci(bci); } write_header(writer, HPROF_FRAME, 4*oopSize + 2*sizeof(u4)); writer->write_id(frame_serial_num); // frame serial number writer->write_objectID(m->name()); // method's name writer->write_objectID(m->signature()); // method's signature assert(Klass::cast(m->method_holder())->oop_is_instance(), "not instanceKlass"); writer->write_objectID(instanceKlass::cast(m->method_holder())->source_file_name()); // source file name writer->write_u4(class_serial_num); // class serial number writer->write_u4((u4) line_number); // line number } // Support class used to generate HPROF_UTF8 records from the entries in the // SymbolTable. class SymbolTableDumper : public OopClosure { private: DumpWriter* _writer; DumpWriter* writer() const { return _writer; } public: SymbolTableDumper(DumpWriter* writer) { _writer = writer; } void do_oop(oop* obj_p); void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } }; void SymbolTableDumper::do_oop(oop* obj_p) { ResourceMark rm; symbolOop sym = (symbolOop)*obj_p; int len = sym->utf8_length(); if (len > 0) { char* s = sym->as_utf8(); DumperSupport::write_header(writer(), HPROF_UTF8, oopSize + len); writer()->write_objectID(sym); writer()->write_raw(s, len); } } // Support class used to generate HPROF_GC_ROOT_JNI_LOCAL records class JNILocalsDumper : public OopClosure { private: DumpWriter* _writer; u4 _thread_serial_num; int _frame_num; DumpWriter* writer() const { return _writer; } public: JNILocalsDumper(DumpWriter* writer, u4 thread_serial_num) { _writer = writer; _thread_serial_num = thread_serial_num; _frame_num = -1; // default - empty stack } void set_frame_number(int n) { _frame_num = n; } void do_oop(oop* obj_p); void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } }; void JNILocalsDumper::do_oop(oop* obj_p) { // ignore null or deleted handles oop o = *obj_p; if (o != NULL && o != JNIHandles::deleted_handle()) { writer()->write_u1(HPROF_GC_ROOT_JNI_LOCAL); writer()->write_objectID(o); writer()->write_u4(_thread_serial_num); writer()->write_u4((u4)_frame_num); } } // Support class used to generate HPROF_GC_ROOT_JNI_GLOBAL records class JNIGlobalsDumper : public OopClosure { private: DumpWriter* _writer; DumpWriter* writer() const { return _writer; } public: JNIGlobalsDumper(DumpWriter* writer) { _writer = writer; } void do_oop(oop* obj_p); void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } }; void JNIGlobalsDumper::do_oop(oop* obj_p) { oop o = *obj_p; // ignore these if (o == NULL || o == JNIHandles::deleted_handle()) return; // we ignore global ref to symbols and other internal objects if (o->is_instance() || o->is_objArray() || o->is_typeArray()) { writer()->write_u1(HPROF_GC_ROOT_JNI_GLOBAL); writer()->write_objectID(o); writer()->write_objectID((oopDesc*)obj_p); // global ref ID } }; // Support class used to generate HPROF_GC_ROOT_MONITOR_USED records class MonitorUsedDumper : public OopClosure { private: DumpWriter* _writer; DumpWriter* writer() const { return _writer; } public: MonitorUsedDumper(DumpWriter* writer) { _writer = writer; } void do_oop(oop* obj_p) { writer()->write_u1(HPROF_GC_ROOT_MONITOR_USED); writer()->write_objectID(*obj_p); } void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } }; // Support class used to generate HPROF_GC_ROOT_STICKY_CLASS records class StickyClassDumper : public OopClosure { private: DumpWriter* _writer; DumpWriter* writer() const { return _writer; } public: StickyClassDumper(DumpWriter* writer) { _writer = writer; } void do_oop(oop* obj_p); void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } }; void StickyClassDumper::do_oop(oop* obj_p) { if (*obj_p != NULL) { oop o = *obj_p; if (o->is_klass()) { klassOop k = klassOop(o); if (Klass::cast(k)->oop_is_instance()) { instanceKlass* ik = instanceKlass::cast(k); writer()->write_u1(HPROF_GC_ROOT_STICKY_CLASS); writer()->write_classID(ik); } } } } class VM_HeapDumper; // Support class using when iterating over the heap. class HeapObjectDumper : public ObjectClosure { private: VM_HeapDumper* _dumper; DumpWriter* _writer; VM_HeapDumper* dumper() { return _dumper; } DumpWriter* writer() { return _writer; } // used to indicate that a record has been writen void mark_end_of_record(); public: HeapObjectDumper(VM_HeapDumper* dumper, DumpWriter* writer) { _dumper = dumper; _writer = writer; } // called for each object in the heap void do_object(oop o); }; void HeapObjectDumper::do_object(oop o) { // hide the sentinel for deleted handles if (o == JNIHandles::deleted_handle()) return; // ignore KlassKlass objects if (o->is_klass()) return; // skip classes as these emitted as HPROF_GC_CLASS_DUMP records if (o->klass() == SystemDictionary::class_klass()) { if (!java_lang_Class::is_primitive(o)) { return; } } // create a HPROF_GC_INSTANCE record for each object if (o->is_instance()) { DumperSupport::dump_instance(writer(), o); mark_end_of_record(); } else { // create a HPROF_GC_OBJ_ARRAY_DUMP record for each object array if (o->is_objArray()) { DumperSupport::dump_object_array(writer(), objArrayOop(o)); mark_end_of_record(); } else { // create a HPROF_GC_PRIM_ARRAY_DUMP record for each type array if (o->is_typeArray()) { DumperSupport::dump_prim_array(writer(), typeArrayOop(o)); mark_end_of_record(); } } } } // The VM operation that performs the heap dump class VM_HeapDumper : public VM_GC_Operation { private: static VM_HeapDumper* _global_dumper; static DumpWriter* _global_writer; DumpWriter* _local_writer; bool _gc_before_heap_dump; bool _is_segmented_dump; jlong _dump_start; GrowableArray<Klass*>* _klass_map; ThreadStackTrace** _stack_traces; int _num_threads; // accessors and setters static VM_HeapDumper* dumper() { assert(_global_dumper != NULL, "Error"); return _global_dumper; } static DumpWriter* writer() { assert(_global_writer != NULL, "Error"); return _global_writer; } void set_global_dumper() { assert(_global_dumper == NULL, "Error"); _global_dumper = this; } void set_global_writer() { assert(_global_writer == NULL, "Error"); _global_writer = _local_writer; } void clear_global_dumper() { _global_dumper = NULL; } void clear_global_writer() { _global_writer = NULL; } bool is_segmented_dump() const { return _is_segmented_dump; } void set_segmented_dump() { _is_segmented_dump = true; } jlong dump_start() const { return _dump_start; } void set_dump_start(jlong pos); bool skip_operation() const; // writes a HPROF_LOAD_CLASS record static void do_load_class(klassOop k); // writes a HPROF_GC_CLASS_DUMP record for the given class // (and each array class too) static void do_class_dump(klassOop k); // writes a HPROF_GC_CLASS_DUMP records for a given basic type // array (and each multi-dimensional array too) static void do_basic_type_array_class_dump(klassOop k); // HPROF_GC_ROOT_THREAD_OBJ records int do_thread(JavaThread* thread, u4 thread_serial_num); void do_threads(); void add_class_serial_number(Klass* k, int serial_num) { _klass_map->at_put_grow(serial_num, k); } // HPROF_TRACE and HPROF_FRAME records void dump_stack_traces(); // writes a HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT record void write_dump_header(); // fixes up the length of the current dump record void write_current_dump_record_length(); // fixes up the current dump record )and writes HPROF_HEAP_DUMP_END // record in the case of a segmented heap dump) void end_of_dump(); public: VM_HeapDumper(DumpWriter* writer, bool gc_before_heap_dump) : VM_GC_Operation(0 /* total collections, dummy, ignored */, 0 /* total full collections, dummy, ignored */, gc_before_heap_dump) { _local_writer = writer; _gc_before_heap_dump = gc_before_heap_dump; _is_segmented_dump = false; _dump_start = (jlong)-1; _klass_map = new (ResourceObj::C_HEAP) GrowableArray<Klass*>(INITIAL_CLASS_COUNT, true); _stack_traces = NULL; _num_threads = 0; } ~VM_HeapDumper() { if (_stack_traces != NULL) { for (int i=0; i < _num_threads; i++) { delete _stack_traces[i]; } FREE_C_HEAP_ARRAY(ThreadStackTrace*, _stack_traces); } delete _klass_map; } VMOp_Type type() const { return VMOp_HeapDumper; } // used to mark sub-record boundary void check_segment_length(); void doit(); }; VM_HeapDumper* VM_HeapDumper::_global_dumper = NULL; DumpWriter* VM_HeapDumper::_global_writer = NULL; bool VM_HeapDumper::skip_operation() const { return false; } // sets the dump starting position void VM_HeapDumper::set_dump_start(jlong pos) { _dump_start = pos; } // writes a HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT record void VM_HeapDumper::write_dump_header() { if (writer()->is_open()) { if (is_segmented_dump()) { writer()->write_u1(HPROF_HEAP_DUMP_SEGMENT); } else { writer()->write_u1(HPROF_HEAP_DUMP); } writer()->write_u4(0); // current ticks // record the starting position for the dump (its length will be fixed up later) set_dump_start(writer()->current_offset()); writer()->write_u4(0); } } // fixes up the length of the current dump record void VM_HeapDumper::write_current_dump_record_length() { if (writer()->is_open()) { assert(dump_start() >= 0, "no dump start recorded"); // calculate the size of the dump record jlong dump_end = writer()->current_offset(); jlong dump_len = (dump_end - dump_start() - 4); // record length must fit in a u4 if (dump_len > (jlong)(4L*(jlong)G)) { warning("record is too large"); } // seek to the dump start and fix-up the length writer()->seek_to_offset(dump_start()); writer()->write_u4((u4)dump_len); // adjust the total size written to keep the bytes written correct. writer()->adjust_bytes_written(-((long) sizeof(u4))); // seek to dump end so we can continue writer()->seek_to_offset(dump_end); // no current dump record set_dump_start((jlong)-1); } } // used on a sub-record boundary to check if we need to start a // new segment. void VM_HeapDumper::check_segment_length() { if (writer()->is_open()) { if (is_segmented_dump()) { // don't use current_offset that would be too expensive on a per record basis jlong dump_end = writer()->bytes_written() + writer()->bytes_unwritten(); assert(dump_end == writer()->current_offset(), "checking"); jlong dump_len = (dump_end - dump_start() - 4); assert(dump_len >= 0 && dump_len <= max_juint, "bad dump length"); if (dump_len > (jlong)HeapDumpSegmentSize) { write_current_dump_record_length(); write_dump_header(); } } } } // fixes up the current dump record )and writes HPROF_HEAP_DUMP_END // record in the case of a segmented heap dump) void VM_HeapDumper::end_of_dump() { if (writer()->is_open()) { write_current_dump_record_length(); // for segmented dump we write the end record if (is_segmented_dump()) { writer()->write_u1(HPROF_HEAP_DUMP_END); writer()->write_u4(0); writer()->write_u4(0); } } } // marks sub-record boundary void HeapObjectDumper::mark_end_of_record() { dumper()->check_segment_length(); } // writes a HPROF_LOAD_CLASS record for the class (and each of its // array classes) void VM_HeapDumper::do_load_class(klassOop k) { static u4 class_serial_num = 0; // len of HPROF_LOAD_CLASS record u4 remaining = 2*oopSize + 2*sizeof(u4); // write a HPROF_LOAD_CLASS for the class and each array class do { DumperSupport::write_header(writer(), HPROF_LOAD_CLASS, remaining); // class serial number is just a number writer()->write_u4(++class_serial_num); // class ID Klass* klass = Klass::cast(k); writer()->write_classID(klass); // add the klassOop and class serial number pair dumper()->add_class_serial_number(klass, class_serial_num); writer()->write_u4(STACK_TRACE_ID); // class name ID symbolOop name = klass->name(); writer()->write_objectID(name); // write a LOAD_CLASS record for the array type (if it exists) k = klass->array_klass_or_null(); } while (k != NULL); } // writes a HPROF_GC_CLASS_DUMP record for the given class void VM_HeapDumper::do_class_dump(klassOop k) { DumperSupport::dump_class_and_array_classes(writer(), k); } // writes a HPROF_GC_CLASS_DUMP records for a given basic type // array (and each multi-dimensional array too) void VM_HeapDumper::do_basic_type_array_class_dump(klassOop k) { DumperSupport::dump_basic_type_array_class(writer(), k); } // Walk the stack of the given thread. // Dumps a HPROF_GC_ROOT_JAVA_FRAME record for each local // Dumps a HPROF_GC_ROOT_JNI_LOCAL record for each JNI local // // It returns the number of Java frames in this thread stack int VM_HeapDumper::do_thread(JavaThread* java_thread, u4 thread_serial_num) { JNILocalsDumper blk(writer(), thread_serial_num); oop threadObj = java_thread->threadObj(); assert(threadObj != NULL, "sanity check"); int stack_depth = 0; if (java_thread->has_last_Java_frame()) { // vframes are resource allocated Thread* current_thread = Thread::current(); ResourceMark rm(current_thread); HandleMark hm(current_thread); RegisterMap reg_map(java_thread); frame f = java_thread->last_frame(); vframe* vf = vframe::new_vframe(&f, ®_map, java_thread); frame* last_entry_frame = NULL; while (vf != NULL) { blk.set_frame_number(stack_depth); if (vf->is_java_frame()) { // java frame (interpreted, compiled, ...) javaVFrame *jvf = javaVFrame::cast(vf); if (!(jvf->method()->is_native())) { StackValueCollection* locals = jvf->locals(); for (int slot=0; slot<locals->size(); slot++) { if (locals->at(slot)->type() == T_OBJECT) { oop o = locals->obj_at(slot)(); if (o != NULL) { writer()->write_u1(HPROF_GC_ROOT_JAVA_FRAME); writer()->write_objectID(o); writer()->write_u4(thread_serial_num); writer()->write_u4((u4) stack_depth); } } } } else { // native frame if (stack_depth == 0) { // JNI locals for the top frame. java_thread->active_handles()->oops_do(&blk); } else { if (last_entry_frame != NULL) { // JNI locals for the entry frame assert(last_entry_frame->is_entry_frame(), "checking"); last_entry_frame->entry_frame_call_wrapper()->handles()->oops_do(&blk); } } } // increment only for Java frames stack_depth++; last_entry_frame = NULL; } else { // externalVFrame - if it's an entry frame then report any JNI locals // as roots when we find the corresponding native javaVFrame frame* fr = vf->frame_pointer(); assert(fr != NULL, "sanity check"); if (fr->is_entry_frame()) { last_entry_frame = fr; } } vf = vf->sender(); } } else { // no last java frame but there may be JNI locals java_thread->active_handles()->oops_do(&blk); } return stack_depth; } // write a HPROF_GC_ROOT_THREAD_OBJ record for each java thread. Then walk // the stack so that locals and JNI locals are dumped. void VM_HeapDumper::do_threads() { for (int i=0; i < _num_threads; i++) { JavaThread* thread = _stack_traces[i]->thread(); oop threadObj = thread->threadObj(); u4 thread_serial_num = i+1; u4 stack_serial_num = thread_serial_num + STACK_TRACE_ID; writer()->write_u1(HPROF_GC_ROOT_THREAD_OBJ); writer()->write_objectID(threadObj); writer()->write_u4(thread_serial_num); // thread number writer()->write_u4(stack_serial_num); // stack trace serial number int num_frames = do_thread(thread, thread_serial_num); assert(num_frames == _stack_traces[i]->get_stack_depth(), "total number of Java frames not matched"); } } // The VM operation that dumps the heap. The dump consists of the following // records: // // HPROF_HEADER // [HPROF_UTF8]* // [HPROF_LOAD_CLASS]* // [[HPROF_FRAME]*|HPROF_TRACE]* // [HPROF_GC_CLASS_DUMP]* // HPROF_HEAP_DUMP // // The HPROF_TRACE records represent the stack traces where the heap dump // is generated and a "dummy trace" record which does not include // any frames. The dummy trace record is used to be referenced as the // unknown object alloc site. // // The HPROF_HEAP_DUMP record has a length following by sub-records. To allow // the heap dump be generated in a single pass we remember the position of // the dump length and fix it up after all sub-records have been written. // To generate the sub-records we iterate over the heap, writing // HPROF_GC_INSTANCE_DUMP, HPROF_GC_OBJ_ARRAY_DUMP, and HPROF_GC_PRIM_ARRAY_DUMP // records as we go. Once that is done we write records for some of the GC // roots. void VM_HeapDumper::doit() { HandleMark hm; CollectedHeap* ch = Universe::heap(); if (_gc_before_heap_dump) { ch->collect_as_vm_thread(GCCause::_heap_dump); } else { // make the heap parsable (no need to retire TLABs) ch->ensure_parsability(false); } // At this point we should be the only dumper active, so // the following should be safe. set_global_dumper(); set_global_writer(); // Write the file header - use 1.0.2 for large heaps, otherwise 1.0.1 size_t used = ch->used(); const char* header; if (used > (size_t)SegmentedHeapDumpThreshold) { set_segmented_dump(); header = "JAVA PROFILE 1.0.2"; } else { header = "JAVA PROFILE 1.0.1"; } // header is few bytes long - no chance to overflow int writer()->write_raw((void*)header, (int)strlen(header)); writer()->write_u1(0); // terminator writer()->write_u4(oopSize); writer()->write_u8(os::javaTimeMillis()); // HPROF_UTF8 records SymbolTableDumper sym_dumper(writer()); SymbolTable::oops_do(&sym_dumper); // write HPROF_LOAD_CLASS records SystemDictionary::classes_do(&do_load_class); Universe::basic_type_classes_do(&do_load_class); // write HPROF_FRAME and HPROF_TRACE records // this must be called after _klass_map is built when iterating the classes above. dump_stack_traces(); // write HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT write_dump_header(); // Writes HPROF_GC_CLASS_DUMP records SystemDictionary::classes_do(&do_class_dump); Universe::basic_type_classes_do(&do_basic_type_array_class_dump); check_segment_length(); // writes HPROF_GC_INSTANCE_DUMP records. // After each sub-record is written check_segment_length will be invoked. When // generated a segmented heap dump this allows us to check if the current // segment exceeds a threshold and if so, then a new segment is started. // The HPROF_GC_CLASS_DUMP and HPROF_GC_INSTANCE_DUMP are the vast bulk // of the heap dump. HeapObjectDumper obj_dumper(this, writer()); Universe::heap()->safe_object_iterate(&obj_dumper); // HPROF_GC_ROOT_THREAD_OBJ + frames + jni locals do_threads(); check_segment_length(); // HPROF_GC_ROOT_MONITOR_USED MonitorUsedDumper mon_dumper(writer()); ObjectSynchronizer::oops_do(&mon_dumper); check_segment_length(); // HPROF_GC_ROOT_JNI_GLOBAL JNIGlobalsDumper jni_dumper(writer()); JNIHandles::oops_do(&jni_dumper); check_segment_length(); // HPROF_GC_ROOT_STICKY_CLASS StickyClassDumper class_dumper(writer()); SystemDictionary::always_strong_oops_do(&class_dumper); // fixes up the length of the dump record. In the case of a segmented // heap then the HPROF_HEAP_DUMP_END record is also written. end_of_dump(); // Now we clear the global variables, so that a future dumper might run. clear_global_dumper(); clear_global_writer(); } void VM_HeapDumper::dump_stack_traces() { // write a HPROF_TRACE record without any frames to be referenced as object alloc sites DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4)); writer()->write_u4((u4) STACK_TRACE_ID); writer()->write_u4(0); // thread number writer()->write_u4(0); // frame count _stack_traces = NEW_C_HEAP_ARRAY(ThreadStackTrace*, Threads::number_of_threads()); int frame_serial_num = 0; for (JavaThread* thread = Threads::first(); thread != NULL ; thread = thread->next()) { oop threadObj = thread->threadObj(); if (threadObj != NULL && !thread->is_exiting() && !thread->is_hidden_from_external_view()) { // dump thread stack trace ThreadStackTrace* stack_trace = new ThreadStackTrace(thread, false); stack_trace->dump_stack_at_safepoint(-1); _stack_traces[_num_threads++] = stack_trace; // write HPROF_FRAME records for this thread's stack trace int depth = stack_trace->get_stack_depth(); int thread_frame_start = frame_serial_num; for (int j=0; j < depth; j++) { StackFrameInfo* frame = stack_trace->stack_frame_at(j); methodOop m = frame->method(); int class_serial_num = _klass_map->find(Klass::cast(m->method_holder())); // the class serial number starts from 1 assert(class_serial_num > 0, "class not found"); DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, class_serial_num, m, frame->bci()); } // write HPROF_TRACE record for one thread DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4) + depth*oopSize); int stack_serial_num = _num_threads + STACK_TRACE_ID; writer()->write_u4(stack_serial_num); // stack trace serial number writer()->write_u4((u4) _num_threads); // thread serial number writer()->write_u4(depth); // frame count for (int j=1; j <= depth; j++) { writer()->write_id(thread_frame_start + j); } } } } // dump the heap to given path. int HeapDumper::dump(const char* path) { assert(path != NULL && strlen(path) > 0, "path missing"); // print message in interactive case if (print_to_tty()) { tty->print_cr("Dumping heap to %s ...", path); timer()->start(); } // create the dump writer. If the file can be opened then bail DumpWriter writer(path); if (!writer.is_open()) { set_error(writer.error()); if (print_to_tty()) { tty->print_cr("Unable to create %s: %s", path, (error() != NULL) ? error() : "reason unknown"); } return -1; } // generate the dump VM_HeapDumper dumper(&writer, _gc_before_heap_dump); if (Thread::current()->is_VM_thread()) { assert(SafepointSynchronize::is_at_safepoint(), "Expected to be called at a safepoint"); dumper.doit(); } else { VMThread::execute(&dumper); } // close dump file and record any error that the writer may have encountered writer.close(); set_error(writer.error()); // print message in interactive case if (print_to_tty()) { timer()->stop(); if (error() == NULL) { char msg[256]; sprintf(msg, "Heap dump file created [%s bytes in %3.3f secs]", os::jlong_format_specifier(), timer()->seconds()); tty->print_cr(msg, writer.bytes_written()); } else { tty->print_cr("Dump file is incomplete: %s", writer.error()); } } return (writer.error() == NULL) ? 0 : -1; } // stop timer (if still active), and free any error string we might be holding HeapDumper::~HeapDumper() { if (timer()->is_active()) { timer()->stop(); } set_error(NULL); } // returns the error string (resource allocated), or NULL char* HeapDumper::error_as_C_string() const { if (error() != NULL) { char* str = NEW_RESOURCE_ARRAY(char, strlen(error())+1); strcpy(str, error()); return str; } else { return NULL; } } // set the error string void HeapDumper::set_error(char* error) { if (_error != NULL) { os::free(_error); } if (error == NULL) { _error = NULL; } else { _error = os::strdup(error); assert(_error != NULL, "allocation failure"); } } // Called by error reporting by a single Java thread outside of a JVM safepoint, // or by heap dumping by the VM thread during a (GC) safepoint. Thus, these various // callers are strictly serialized and guaranteed not to interfere below. For more // general use, however, this method will need modification to prevent // inteference when updating the static variables base_path and dump_file_seq below. void HeapDumper::dump_heap() { static char base_path[JVM_MAXPATHLEN] = {'\0'}; static uint dump_file_seq = 0; char my_path[JVM_MAXPATHLEN] = {'\0'}; // The dump file defaults to java_pid<pid>.hprof in the current working // directory. HeapDumpPath=<file> can be used to specify an alternative // dump file name or a directory where dump file is created. if (dump_file_seq == 0) { // first time in, we initialize base_path bool use_default_filename = true; if (HeapDumpPath == NULL || HeapDumpPath[0] == '\0') { // HeapDumpPath=<file> not specified } else { assert(strlen(HeapDumpPath) < sizeof(base_path), "HeapDumpPath too long"); strcpy(base_path, HeapDumpPath); // check if the path is a directory (must exist) DIR* dir = os::opendir(base_path); if (dir == NULL) { use_default_filename = false; } else { // HeapDumpPath specified a directory. We append a file separator // (if needed). os::closedir(dir); size_t fs_len = strlen(os::file_separator()); if (strlen(base_path) >= fs_len) { char* end = base_path; end += (strlen(base_path) - fs_len); if (strcmp(end, os::file_separator()) != 0) { assert(strlen(base_path) + strlen(os::file_separator()) < sizeof(base_path), "HeapDumpPath too long"); strcat(base_path, os::file_separator()); } } } } // If HeapDumpPath wasn't a file name then we append the default name if (use_default_filename) { char fn[32]; sprintf(fn, "java_pid%d", os::current_process_id()); assert(strlen(base_path) + strlen(fn) + strlen(".hprof") < sizeof(base_path), "HeapDumpPath too long"); strcat(base_path, fn); strcat(base_path, ".hprof"); } assert(strlen(base_path) < sizeof(my_path), "Buffer too small"); strcpy(my_path, base_path); } else { // Append a sequence number id for dumps following the first char fn[33]; sprintf(fn, ".%d", dump_file_seq); assert(strlen(base_path) + strlen(fn) < sizeof(my_path), "HeapDumpPath too long"); strcpy(my_path, base_path); strcat(my_path, fn); } dump_file_seq++; // increment seq number for next time we dump HeapDumper dumper(false /* no GC before heap dump */, true /* send to tty */); dumper.dump(my_path); }