Mercurial > hg > graal-jvmci-8
view src/share/vm/memory/filemap.hpp @ 1994:6cd6d394f280
7001033: assert(gch->gc_cause() == GCCause::_scavenge_alot || !gch->incremental_collection_failed())
7002546: regression on SpecJbb2005 on 7b118 comparing to 7b117 on small heaps
Summary: Relaxed assertion checking related to incremental_collection_failed flag to allow for ExplicitGCInvokesConcurrent behaviour where we do not want a failing scavenge to bail to a stop-world collection. Parameterized incremental_collection_will_fail() so we can selectively use, or not use, as appropriate, the statistical prediction at specific use sites. This essentially reverts the scavenge bail-out logic to what it was prior to some recent changes that had inadvertently started using the statistical prediction which can be noisy in the presence of bursty loads. Added some associated verbose non-product debugging messages.
Reviewed-by: johnc, tonyp
author | ysr |
---|---|
date | Tue, 07 Dec 2010 21:55:53 -0800 |
parents | f95d63e2154a |
children | d2a62e0f25eb |
line wrap: on
line source
/* * Copyright (c) 2003, 2010, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #ifndef SHARE_VM_MEMORY_FILEMAP_HPP #define SHARE_VM_MEMORY_FILEMAP_HPP #include "memory/compactingPermGenGen.hpp" #include "memory/space.hpp" // Layout of the file: // header: dump of archive instance plus versioning info, datestamp, etc. // [magic # = 0xF00BABA2] // ... padding to align on page-boundary // read-write space from CompactingPermGenGen // read-only space from CompactingPermGenGen // misc data (block offset table, string table, symbols, dictionary, etc.) // tag(666) static const int JVM_SHARED_JARS_MAX = 128; static const int JVM_SPACENAME_MAX = 128; static const int JVM_IDENT_MAX = 256; static const int JVM_ARCH_MAX = 12; class FileMapInfo : public CHeapObj { private: enum { _invalid_version = -1, _current_version = 1 }; bool _file_open; int _fd; long _file_offset; // FileMapHeader describes the shared space data in the file to be // mapped. This structure gets written to a file. It is not a class, so // that the compilers don't add any compiler-private data to it. struct FileMapHeader { int _magic; // identify file type. int _version; // (from enum, above.) size_t _alignment; // how shared archive should be aligned struct space_info { int _file_offset; // sizeof(this) rounded to vm page size char* _base; // copy-on-write base address size_t _capacity; // for validity checking size_t _used; // for setting space top on read bool _read_only; // read only space? bool _allow_exec; // executable code in space? } _space[CompactingPermGenGen::n_regions]; // The following fields are all sanity checks for whether this archive // will function correctly with this JVM and the bootclasspath it's // invoked with. char _arch[JVM_ARCH_MAX]; // architecture char _jvm_ident[JVM_IDENT_MAX]; // identifier for jvm int _num_jars; // Number of jars in bootclasspath // Per jar file data: timestamp, size. struct { time_t _timestamp; // jar timestamp. long _filesize; // jar file size. } _jar[JVM_SHARED_JARS_MAX]; } _header; const char* _full_path; static FileMapInfo* _current_info; bool init_from_file(int fd); void align_file_position(); public: FileMapInfo() { _file_offset = 0; _file_open = false; _header._version = _invalid_version; } static int current_version() { return _current_version; } void populate_header(size_t alignment); bool validate(); void invalidate(); int version() { return _header._version; } size_t alignment() { return _header._alignment; } size_t space_capacity(int i) { return _header._space[i]._capacity; } char* region_base(int i) { return _header._space[i]._base; } struct FileMapHeader* header() { return &_header; } static void set_current_info(FileMapInfo* info) { _current_info = info; } static FileMapInfo* current_info() { return _current_info; } static void assert_mark(bool check); // File manipulation. bool initialize(); bool open_for_read(); void open_for_write(); void write_header(); void write_space(int i, CompactibleSpace* space, bool read_only); void write_region(int region, char* base, size_t size, size_t capacity, bool read_only, bool allow_exec); void write_bytes(const void* buffer, int count); void write_bytes_aligned(const void* buffer, int count); bool map_space(int i, ReservedSpace rs, ContiguousSpace *space); char* map_region(int i, ReservedSpace rs); char* map_region(int i, bool address_must_match); void unmap_region(int i); void close(); bool is_open() { return _file_open; } // JVM/TI RedefineClasses() support: // Remap the shared readonly space to shared readwrite, private. bool remap_shared_readonly_as_readwrite(); // Errors. static void fail_stop(const char *msg, ...); void fail_continue(const char *msg, ...); // Return true if given address is in the mapped shared space. bool is_in_shared_space(const void* p); }; #endif // SHARE_VM_MEMORY_FILEMAP_HPP