STXXL (GIT-copy)

#ifndef IOSTATS_HEADER
#define IOSTATS_HEADER

/***************************************************************************
 *            iostats.h
 *
 *  Sat Aug 24 23:54:50 2002
 *  Copyright  2002  Roman Dementiev
 *  dementiev@mpi-sb.mpg.de
 ****************************************************************************/

#include "../common/mutex.h"
#include "../common/utils.h"

#include <iostream>

__STXXL_BEGIN_NAMESPACE

  //! \addtogroup iolayer
  //!
  //! \{

#ifdef COUNT_WAIT_TIME
#ifdef BOOST_MSVC
extern double wait_time_counter;
#else
extern double stxxl::wait_time_counter;
#endif
#endif

	class disk_queue;

	//! \brief Collects varoius I/O statistics
	//! \remarks is a singleton
	class stats
	{
		friend class disk_queue;
		unsigned reads, writes;	// number of operations
		int64 volume_read,volume_written; // number of bytes read/written
		double t_reads, t_writes;	//  seconds spent in operations
		double p_reads, p_writes;	// seconds spent in parallel operations
		double p_begin_read, p_begin_write;	// start time of parallel operation
		double p_ios;	// seconds spent in all parallel I/O operations (read and write)
		double p_begin_io;
		int acc_ios;
		int acc_reads, acc_writes;	// number of requests, participating in parallel operation
		double last_reset;
		#ifdef STXXL_BOOST_THREADS
		boost::mutex read_mutex, write_mutex, io_mutex;
		#else
		mutex read_mutex, write_mutex, io_mutex;
		#endif

		static stats * instance;
		
		stats ();
	public:
		//! \brief Call this function in order to access an instance of stats
		//! \return pointer to an instance of stats
		static stats *get_instance ();
		//! \brief Returns total number of reads
		//! \return total number of reads
		unsigned get_reads () const;
		//! \brief Returns total number of writes
		//! \return total number of writes
		unsigned get_writes () const;
		//! \brief Returns number of bytes read from disks
		//! \return number of bytes read
		int64 get_read_volume () const;
		//! \brief Returns number of bytes written to the disks
		//! \return number of bytes written
		int64 get_written_volume () const;
		//! \brief Returns time spent in serving all read requests
		//! \remarks If there are \c n read requests that are served simultaneously
		//! \remarks in 1 second then the counter corresponding to the function increments by \c n seconds
		//! \return seconds spent in reading
		double get_read_time () const;
		//! \brief Returns total time spent in serving all write requests
		//! \remarks If there are \c n write requests that are served simultaneously
		//! \remarks in 1 second then the counter corresponding to the function increments by \c n seconds
		//! \return seconds spent in writing
		double get_write_time () const;
		//! \brief Returns time spent in reading (parallel read time)
		//! \remarks If there are \c n read requests that are served simultaneously
		//! \remarks in 1 second then the counter corresponding to the function increments by 1 second
		//! \return seconds spent in reading
		double get_pread_time() const;
		//! \brief Returns time spent in writing (parallel write time)
		//! \remarks If there are \c n write requests that are served simultaneously
		//! \remarks in 1 second then the counter corresponding to the function increments by 1 second
		//! \return seconds spent in writing
		double get_pwrite_time() const;
		//! \brief Returns time spent in I/O (parallel I/O time)
		//! \remarks If there are \c n \b any requests that are served simultaneously
		//! \remarks in 1 second then the counter corresponding to the function increments by 1 second
		//! \return seconds spent in I/O
		double get_pio_time() const;
		//! \brief Return time of the last reset
		//! \return The returned value is in seconds
		double get_last_reset_time() const;
		//! \brief Resets I/O time counters (including I/O wait counter)
		void reset();
		
		
#ifdef COUNT_WAIT_TIME
		//! \brief Resets I/O wait time counter
		void _reset_io_wait_time() ;
		// void reset_io_wait_time() { stxxl::wait_time_counter = 0.0; }
		//! \brief Returns I/O wait time counter
		//! \return number of seconds spent in I/O waiting functions 
		//!  \link request::wait request::wait \endlink,
		//!  \c wait_any and
		//!  \c wait_all 
		double get_io_wait_time() const ;
		//! \brief Increments I/O wait time counter
		//! \param val increment value in seconds
		//! \return new value of I/O wait time counter in seconds
		double increment_io_wait_time(double val);
#else
		//! \brief Resets I/O wait time counter
		void _reset_io_wait_time();
		//! \brief Returns I/O wait time counter
		//! \return number of seconds spent in I/O waiting functions 
		//!  \link request::wait request::wait \endlink,
		//!  \c wait_any and
		//!  \c wait_all 
		//! \return number of seconds
		double get_io_wait_time() const;
		//! \brief Increments I/O wait time counter
		//! \param val increment value in seconds
		//! \return new value of I/O wait time counter in seconds
		double increment_io_wait_time(double val);
#endif
		
		// for library use
		void write_started (unsigned size_);
		void write_finished ();
		void read_started (unsigned size_);
		void read_finished ();
	};
	
	#ifndef DISKQUEUE_HEADER
	
	std::ostream & operator << (std::ostream & o, const stats & s);
	
	#endif
	
//! \}

__STXXL_END_NAMESPACE

#endif