stats Class Reference
[I/O primitives layer]

Collects various I/O statistics. More...

#include <iostats.h>

Inherits noncopyable.

Collaboration diagram for stats:

[legend]

List of all members.

Public Member Functions
unsigned	get_reads () const
	Returns total number of reads.
unsigned	get_writes () const
	Returns total number of writes.
int64	get_read_volume () const
	Returns number of bytes read from disks.
int64	get_written_volume () const
	Returns number of bytes written to the disks.
double	get_read_time () const
	Time that would be spent in read syscalls if all parallel reads were serialized.
double	get_write_time () const
	Time that would be spent in write syscalls if all parallel writes were serialized.
double	get_pread_time () const
	Period of time when at least one I/O thread was executing a read.
double	get_pwrite_time () const
	Period of time when at least one I/O thread was executing a write.
double	get_pio_time () const
	Period of time when at least one I/O thread was executing a read or a write.
double	get_last_reset_time () const
	Return time of the last reset.
void	reset ()
	Resets I/O time counters (including I/O wait counter).
void	_reset_io_wait_time ()
	Resets I/O wait time counter.
double	get_io_wait_time () const
	I/O wait time counter.
double	increment_io_wait_time (double val)
	Increments I/O wait time counter.
Static Public Member Functions
static stats *	get_instance ()
	Call this function in order to access an instance of stats.

---

Detailed Description

Collects various I/O statistics.

Remarks:

is a singleton

---

Member Function Documentation

static stats* stats::get_instance

(

)

[inline, static]

Call this function in order to access an instance of stats.

Returns:

pointer to an instance of stats

Referenced by stream::runs_creator< use_push< ValueType_ >, Cmp_, BlockSize_, AllocStr_ >::result(), and stream::runs_creator< Input_, Cmp_, BlockSize_, AllocStr_ >::result().

unsigned stats::get_reads

(

)

const [inline]

Returns total number of reads.

Returns:

total number of reads

unsigned stats::get_writes

(

)

const [inline]

Returns total number of writes.

Returns:

total number of writes

int64 stats::get_read_volume

(

)

const [inline]

Returns number of bytes read from disks.

Returns:

number of bytes read

int64 stats::get_written_volume

(

)

const [inline]

Returns number of bytes written to the disks.

Returns:

number of bytes written

double stats::get_read_time

(

)

const [inline]

Time that would be spent in read syscalls if all parallel reads were serialized.

Returns:

seconds spent in reading

double stats::get_write_time

(

)

const [inline]

Time that would be spent in write syscalls if all parallel writes were serialized.

Returns:

seconds spent in writing

double stats::get_pread_time

(

)

const [inline]

Period of time when at least one I/O thread was executing a read.

Returns:

seconds spent in reading

double stats::get_pwrite_time

(

)

const [inline]

Period of time when at least one I/O thread was executing a write.

Returns:

seconds spent in writing

double stats::get_pio_time

(

)

const [inline]

Period of time when at least one I/O thread was executing a read or a write.

Returns:

seconds spent in I/O

double stats::get_last_reset_time

(

)

const [inline]

Return time of the last reset.

Returns:

seconds passed from the last reset()

void stats::reset

(

)

Resets I/O time counters (including I/O wait counter).

void stats::_reset_io_wait_time

(

)

Resets I/O wait time counter.

double stats::get_io_wait_time

(

)

const

I/O wait time counter.

Returns:

number of seconds spent in I/O waiting functions request::wait , wait_any and wait_all

number of seconds

double stats::increment_io_wait_time

(

double

val

)

Increments I/O wait time counter.

Parameters:

val

increment value in seconds

Returns:

new value of I/O wait time counter in seconds

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The documentation for this class was generated from the following files:

• iostats.h
• iostats.cpp