mariadb/mysys/array.c
Monty 66dde8a54e Added rowid_filter support to Aria
This includes:
- cleanup and optimization of filtering and pushdown engine code.
- Adjusted costs for rowid filters (based on extensive testing
  and profiling).

This made a small two changes to the handler_rowid_filter_is_active()
API:
- One should not call it with a zero pointer!
- One does not need to call handler_rowid_filter_is_active() for every
  row anymore. It is enough to check if filter is active by calling it
  call it during index_init() or when handler::rowid_filter_changed()
  is called

The changes was to avoid unnecessary function calls and checks if
pushdown conditions and rowid_filter is not used.

Updated costs for rowid_filter_lookup() to be closer to reality.
The old cost was based only on rowid_compare_cost. This is now
changed to take into account the overhead in checking the rowid.

Changed the Range_rowid_filter class to use DYNAMIC_ARRAY directly
instead of Dynamic_array<>. This was done to be able to use the new
append_dynamic() functions which gives a notable speed improvment
compared to the old code.  Removing the abstraction also makes
the code easier to understand.

The cost of filtering is now slightly lower than before, which
is reflected in some test cases that is now using rowid filters.
2023-02-03 10:42:28 +03:00

413 lines
11 KiB
C

/* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program 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 for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
/* Handling of arrays that can grow dynamicly. */
#include "mysys_priv.h"
#include "m_string.h"
/*
Initiate dynamic array
SYNOPSIS
init_dynamic_array2()
ps_key Key to register instrumented memory
array Pointer to an array
element_size Size of element
init_buffer Initial buffer pointer
init_alloc Number of initial elements
alloc_increment Increment for adding new elements
my_flags Flags to my_malloc
DESCRIPTION
init_dynamic_array() initiates array and allocate space for
init_alloc eilements.
Array is usable even if space allocation failed, hence, the
function never returns TRUE.
RETURN VALUE
FALSE Ok
*/
my_bool init_dynamic_array2(PSI_memory_key psi_key, DYNAMIC_ARRAY *array,
size_t element_size, void *init_buffer,
size_t init_alloc, size_t alloc_increment,
myf my_flags)
{
DBUG_ENTER("init_dynamic_array2");
if (!alloc_increment)
{
alloc_increment=MY_MAX((8192-MALLOC_OVERHEAD)/element_size,16);
if (init_alloc > 8 && alloc_increment > init_alloc * 2)
alloc_increment=init_alloc*2;
}
array->elements=0;
array->max_element=init_alloc;
array->alloc_increment=alloc_increment;
array->size_of_element=element_size;
array->m_psi_key= psi_key;
array->malloc_flags= my_flags;
DBUG_ASSERT((my_flags & MY_INIT_BUFFER_USED) == 0);
if ((array->buffer= init_buffer))
{
array->malloc_flags|= MY_INIT_BUFFER_USED;
DBUG_RETURN(FALSE);
}
/*
Since the dynamic array is usable even if allocation fails here malloc
should not throw an error
*/
if (init_alloc &&
!(array->buffer= (uchar*) my_malloc(psi_key, element_size*init_alloc,
MYF(my_flags))))
array->max_element=0;
DBUG_RETURN(FALSE);
}
/*
Insert element at the end of array. Allocate memory if needed.
SYNOPSIS
insert_dynamic()
array
element
RETURN VALUE
TRUE Insert failed
FALSE Ok
*/
my_bool insert_dynamic(DYNAMIC_ARRAY *array, const void * element)
{
void *buffer;
if (unlikely(array->elements == array->max_element))
{ /* Call only when necessary */
if (!(buffer=alloc_dynamic(array)))
return TRUE;
}
else
{
buffer=array->buffer+(array->elements * array->size_of_element);
array->elements++;
}
memcpy(buffer, element, array->size_of_element);
return FALSE;
}
/* Fast version of appending to dynamic array */
void init_append_dynamic(DYNAMIC_ARRAY_APPEND *append,
DYNAMIC_ARRAY *array)
{
append->array= array;
append->pos= array->buffer + array->elements * array->size_of_element;
append->end= array->buffer + array->max_element * array->size_of_element;
}
my_bool append_dynamic(DYNAMIC_ARRAY_APPEND *append,
const void *element)
{
DYNAMIC_ARRAY *array= append->array;
size_t size_of_element= array->size_of_element;
if (unlikely(append->pos == append->end))
{
void *buffer;
if (!(buffer=alloc_dynamic(array)))
return TRUE;
append->pos= (uchar*)buffer + size_of_element;
append->end= array->buffer + array->max_element * size_of_element;
memcpy(buffer, element, size_of_element);
}
else
{
array->elements++;
memcpy(append->pos, element, size_of_element);
append->pos+= size_of_element;
}
return FALSE;
}
/*
Alloc space for next element(s)
SYNOPSIS
alloc_dynamic()
array
DESCRIPTION
alloc_dynamic() checks if there is empty space for at least
one element if not tries to allocate space for alloc_increment
elements at the end of array.
RETURN VALUE
pointer Pointer to empty space for element
0 Error
*/
void *alloc_dynamic(DYNAMIC_ARRAY *array)
{
DBUG_ENTER("alloc_dynamic");
DBUG_ASSERT(array->size_of_element); /* Ensure init() is called */
if (array->elements == array->max_element)
{
char *new_ptr;
if (array->malloc_flags & MY_INIT_BUFFER_USED)
{
/*
In this scenario, the buffer is statically preallocated,
so we have to create an all-new malloc since we overflowed
*/
if (!(new_ptr= (char *) my_malloc(array->m_psi_key,
(array->max_element+
array->alloc_increment) *
array->size_of_element,
MYF(array->malloc_flags | MY_WME))))
DBUG_RETURN(0);
if (array->elements)
memcpy(new_ptr, array->buffer,
array->elements * array->size_of_element);
array->malloc_flags&= ~MY_INIT_BUFFER_USED;
}
else if (!(new_ptr=(char*)
my_realloc(array->m_psi_key, array->buffer,
(array->max_element+ array->alloc_increment) *
array->size_of_element,
MYF(MY_WME | MY_ALLOW_ZERO_PTR |
array->malloc_flags))))
DBUG_RETURN(0);
array->buffer= (uchar*) new_ptr;
array->max_element+=array->alloc_increment;
}
DBUG_RETURN(array->buffer+(array->elements++ * array->size_of_element));
}
/*
Pop last element from array.
SYNOPSIS
pop_dynamic()
array
RETURN VALUE
pointer Ok
0 Array is empty
*/
void *pop_dynamic(DYNAMIC_ARRAY *array)
{
if (array->elements)
return array->buffer+(--array->elements * array->size_of_element);
return 0;
}
/*
Replace element in array with given element and index
SYNOPSIS
set_dynamic()
array
element Element to be inserted
idx Index where element is to be inserted
DESCRIPTION
set_dynamic() replaces element in array.
If idx > max_element insert new element. Allocate memory if needed.
RETURN VALUE
TRUE Idx was out of range and allocation of new memory failed
FALSE Ok
*/
my_bool set_dynamic(DYNAMIC_ARRAY *array, const void *element, size_t idx)
{
if (idx >= array->elements)
{
if (idx >= array->max_element && allocate_dynamic(array, idx))
return TRUE;
bzero((uchar*) (array->buffer+array->elements*array->size_of_element),
(idx - array->elements)*array->size_of_element);
array->elements=idx+1;
}
memcpy(array->buffer+(idx * array->size_of_element),element,
array->size_of_element);
return FALSE;
}
/*
Ensure that dynamic array has enough elements
SYNOPSIS
allocate_dynamic()
array
max_elements Numbers of elements that is needed
NOTES
Any new allocated element are NOT initialized
RETURN VALUE
FALSE Ok
TRUE Allocation of new memory failed
*/
my_bool allocate_dynamic(DYNAMIC_ARRAY *array, size_t max_elements)
{
DBUG_ENTER("allocate_dynamic");
if (max_elements >= array->max_element)
{
size_t size;
uchar *new_ptr;
size= (max_elements + array->alloc_increment)/array->alloc_increment;
size*= array->alloc_increment;
if (array->malloc_flags & MY_INIT_BUFFER_USED)
{
/*
In this senerio, the buffer is statically preallocated,
so we have to create an all-new malloc since we overflowed
*/
if (!(new_ptr= (uchar *) my_malloc(array->m_psi_key, size *
array->size_of_element,
MYF(array->malloc_flags | MY_WME))))
DBUG_RETURN(0);
memcpy(new_ptr, array->buffer,
array->elements * array->size_of_element);
array->malloc_flags&= ~MY_INIT_BUFFER_USED;
}
else if (!(new_ptr= (uchar*) my_realloc(array->m_psi_key,
array->buffer,size *
array->size_of_element,
MYF(MY_WME | MY_ALLOW_ZERO_PTR |
array->malloc_flags))))
DBUG_RETURN(TRUE);
array->buffer= new_ptr;
array->max_element= size;
}
DBUG_RETURN(FALSE);
}
/*
Get an element from array by given index
SYNOPSIS
get_dynamic()
array
uchar* Element to be returned. If idx > elements contain zeroes.
idx Index of element wanted.
*/
void get_dynamic(DYNAMIC_ARRAY *array, void *element, size_t idx)
{
if (unlikely(idx >= array->elements))
{
DBUG_PRINT("warning",("To big array idx: %d, array size is %d",
idx,array->elements));
bzero(element,array->size_of_element);
return;
}
memcpy(element,array->buffer+idx*array->size_of_element,
(size_t) array->size_of_element);
}
/*
Empty array by freeing all memory
SYNOPSIS
delete_dynamic()
array Array to be deleted
*/
void delete_dynamic(DYNAMIC_ARRAY *array)
{
/*
Just mark as empty if we are using a static buffer
*/
if (array->buffer && !(array->malloc_flags & MY_INIT_BUFFER_USED))
my_free(array->buffer);
array->buffer= 0;
array->elements= array->max_element= 0;
}
/*
Delete element by given index
SYNOPSIS
delete_dynamic_element()
array
idx Index of element to be deleted
*/
void delete_dynamic_element(DYNAMIC_ARRAY *array, size_t idx)
{
char *ptr= (char*) array->buffer+array->size_of_element*idx;
array->elements--;
memmove(ptr,ptr+array->size_of_element,
(array->elements-idx)*array->size_of_element);
}
/*
Wrapper around delete_dynamic, calling a FREE function on every
element, before releasing the memory
SYNOPSIS
delete_dynamic_with_callback()
array
f The function to be called on every element before
deleting the array;
*/
void delete_dynamic_with_callback(DYNAMIC_ARRAY *array, FREE_FUNC f) {
size_t i;
char *ptr= (char*) array->buffer;
for (i= 0; i < array->elements; i++, ptr+= array->size_of_element) {
f(ptr);
}
delete_dynamic(array);
}
/*
Free unused memory
SYNOPSIS
freeze_size()
array Array to be freed
*/
void freeze_size(DYNAMIC_ARRAY *array)
{
size_t elements;
/*
Do nothing if we are using a static buffer
*/
if (array->malloc_flags & MY_INIT_BUFFER_USED)
return;
elements= MY_MAX(array->elements, 1);
if (array->buffer && array->max_element > elements)
{
array->buffer=(uchar*) my_realloc(array->m_psi_key, array->buffer,
elements * array->size_of_element,
MYF(MY_WME | array->malloc_flags));
array->max_element= elements;
}
}