malloc.h

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/***************************************************************************
 * include/stxxl/bits/utils/malloc.h
 *
 * Part of the STXXL. See http://stxxl.sourceforge.net
 *
 * Copyright (C) 2003 Roman Dementiev <[email protected]>
 * Copyright (C) 2009 Andreas Beckmann <[email protected]>
 *
 * Distributed under the Boost Software License, Version 1.0.
 * (See accompanying file LICENSE_1_0.txt or copy at
 * http://www.boost.org/LICENSE_1_0.txt)
 **************************************************************************/

#ifndef STXXL_UTILS_MALLOC_HEADER
#define STXXL_UTILS_MALLOC_HEADER

#include <stxxl/bits/config.h>

#include <ostream>
#if STXXL_HAVE_MALLINFO_PROTO
 #include <malloc.h>
#endif
#include <cstdlib>

#include <stxxl/bits/namespace.h>
#include <stxxl/bits/unused.h>


STXXL_BEGIN_NAMESPACE


//! Access to some useful malloc statistics.

//! malloc is default C++ allocator
class malloc_stats
{
#if STXXL_HAVE_MALLINFO_PROTO

public:
 typedef int return_type;

 //! Returns number of bytes allocated from system not including mmapped regions.
 return_type from_system_nmmap() const
 {
 struct mallinfo info = mallinfo();
 return info.arena;
 }

 //! Returns number of free chunks.
 return_type free_chunks() const
 {
 struct mallinfo info = mallinfo();
 return info.ordblks;
 }

 //! Number of bytes allocated and in use.
 return_type used() const
 {
 struct mallinfo info = mallinfo();
 return info.uordblks;
 }

 //! Number of bytes allocated but not in use.
 return_type not_used() const
 {
 struct mallinfo info = mallinfo();
 return info.fordblks;
 }

 //! Top-most, releasable (via malloc_trim) space (bytes).
 return_type releasable() const
 {
 struct mallinfo info = mallinfo();
 return info.keepcost;
 }

 //! Maximum total allocated space (bytes) (always 0 ?).
 return_type max_allocated() const
 {
 struct mallinfo info = mallinfo();
 return info.usmblks;
 }

 //! Number of fastbin blocks.
 return_type fastbin_blocks() const
 {
 struct mallinfo info = mallinfo();
 return info.smblks;
 }

 //! Space available in freed fastbin blocks (bytes).
 return_type fastbin_free() const
 {
 struct mallinfo info = mallinfo();
 return info.fsmblks;
 }

 //! Returns number of bytes allocated from system using mmap.
 return_type from_system_mmap() const
 {
 struct mallinfo info = mallinfo();
 return info.hblkhd;
 }

 //! Number of chunks allocated via mmap().
 return_type mmap_chunks() const
 {
 struct mallinfo info = mallinfo();
 return info.hblks;
 }

 //! Returns \b total number of bytes allocated from system including mmapped regions.
 return_type from_system_total() const
 {
 return from_system_nmmap() + from_system_mmap();
 }
#endif
};

//! Prints current malloc statistics in a convenient way.
inline std::ostream& operator << (std::ostream& s, const malloc_stats& st)
{
#if STXXL_HAVE_MALLINFO_PROTO
 s << "MALLOC statistics" << std::endl;
 s << "=================================================================" << std::endl;
 s << "Space allocated from system not using mmap: " << st.from_system_nmmap() << " bytes" << std::endl;
 s << " number of free chunks : " << st.free_chunks() << std::endl;
 s << " space allocated and in use : " << st.used() << " bytes" << std::endl;
 s << " space allocated but not in use : " << st.not_used() << " bytes" << std::endl;
 s << " top-most, releasable (via malloc_trim) space: " << st.releasable() << " bytes" << std::endl;
 s << " maximum total allocated space (?) : " << st.max_allocated() << " bytes" << std::endl;
 s << " FASTBIN blocks " << std::endl;
 s << " number of fastbin blocks: " << st.fastbin_blocks() << std::endl;
 s << " space available in freed fastbin blocks: " << st.fastbin_free() << " bytes" << std::endl;
 s << "Space allocated from system using mmap: " << st.from_system_mmap() << " bytes" << std::endl;
 s << " number of chunks allocated via mmap(): " << st.mmap_chunks() << std::endl;
 s << "Total space allocated from system (mmap and not mmap): " <<
 st.from_system_total() << " bytes" << std::endl;
 s << "=================================================================" << std::endl;
#else
 s << "MALLOC statistics are not supported on this platform";
 STXXL_UNUSED(st);
#endif
 return s;
}

class malloc_setup
{ };

STXXL_END_NAMESPACE

#endif // !STXXL_UTILS_MALLOC_HEADER