[svn-r4842] Purpose:

Feature improvement
Description:
    Re-write how the free-list headers were used, to reduce the amount of space
    added to each malloc request.  Reduced header for array and block free
    list items from 24 bytes to 8 bytes and eliminated the header for fixed-size
    free list items entirely.  This should reduce the amount of memory that the
    library uses.
Platforms tested:
    FreeBSD 4.5 (sleipnir) & IRIX64 6.5 (modi4)
This commit is contained in:
Quincey Koziol 2002-01-17 13:08:00 -05:00
parent 704f31c151
commit 6f445c649d
2 changed files with 53 additions and 72 deletions

View File

@ -182,6 +182,10 @@ H5FL_reg_init(H5FL_reg_head_t *head)
/* Indicate that the free list is initialized */
head->init=1;
/* Make certain that the space allocated is large enough to store a free list pointer (eventually) */
if(head->size<sizeof(void *))
head->size=sizeof(void *);
FUNC_LEAVE (ret_value);
} /* end H5FL_reg_init() */
@ -222,13 +226,8 @@ H5FL_reg_free(H5FL_reg_head_t *head, void *obj)
/* Make certain that the free list is initialized */
assert(head->init);
/* Get the pointer to the info header in front of the block to free */
temp=(H5FL_reg_node_t *)((unsigned char *)obj-sizeof(H5FL_reg_node_t));
#ifdef H5FL_DEBUG
assert(temp->inuse);
temp->inuse=0;
#endif /* H5FL_DEBUG */
/* Alias the pointer to the block to free into a H5FL_reg_node_t node */
temp=(H5FL_reg_node_t *)obj;
/* Link into the free list */
temp->next=head->list;
@ -276,7 +275,6 @@ H5FL_reg_free(H5FL_reg_head_t *head, void *obj)
void *
H5FL_reg_alloc(H5FL_reg_head_t *head, unsigned clear)
{
H5FL_reg_node_t *new_obj; /* Pointer to the new free list node allocated */
void *ret_value; /* Pointer to object to return */
FUNC_ENTER (H5FL_reg_alloc, NULL);
@ -297,11 +295,7 @@ H5FL_reg_alloc(H5FL_reg_head_t *head, unsigned clear)
/* Check for nodes available on the free list first */
if(head->list!=NULL) {
/* Get a pointer to the block on the free list */
ret_value=((char *)(head->list))+sizeof(H5FL_reg_node_t);
#ifdef H5FL_DEBUG
head->list->inuse=1;
#endif /* H5FL_DEBUG */
ret_value=(void *)(head->list);
/* Remove node from free list */
head->list=head->list->next;
@ -316,18 +310,11 @@ H5FL_reg_alloc(H5FL_reg_head_t *head, unsigned clear)
} /* end if */
/* Otherwise allocate a node */
else {
if (NULL==(new_obj = H5FL_malloc(sizeof(H5FL_reg_node_t)+head->size)))
if (NULL==(ret_value = H5FL_malloc(head->size)))
HRETURN_ERROR (H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed");
#ifdef H5FL_DEBUG
new_obj->inuse=1;
#endif /* H5FL_DEBUG */
/* Increment the number of blocks allocated in list */
head->allocated++;
/* Get a pointer to the new block */
ret_value=((char *)new_obj)+sizeof(H5FL_reg_node_t);
} /* end else */
/* Clear to zeros, if asked */
@ -378,10 +365,6 @@ H5FL_reg_gc_list(H5FL_reg_head_t *head)
/* Decrement count of free memory on this list */
head->list_mem-=head->size;
#ifdef H5FL_DEBUG
assert(!free_list->inuse);
#endif /* H5FL_DEBUG */
H5MM_xfree(free_list);
free_list=tmp;
@ -705,10 +688,16 @@ H5FL_blk_alloc(H5FL_blk_head_t *head, size_t size, unsigned clear)
/* check if there is a free list for blocks of this size */
/* and if there are any blocks available on the list */
if((free_list=H5FL_blk_find_list(&(head->head),size))!=NULL && free_list->list!=NULL) {
/* Remove the first node from the list and return it */
ret_value=((char *)(free_list->list))+sizeof(H5FL_blk_list_t);
/* Remove the first node from the free list */
temp=free_list->list;
free_list->list=free_list->list->next;
/* Restore the size of the block */
temp->size=size; /* Overwrites the 'next' field */
/* Return the pointer to the data portion */
ret_value=((char *)temp)+sizeof(H5FL_blk_list_t);
/* Decrement the number of blocks & memory used on free list */
head->onlist--;
head->list_mem-=size;
@ -728,7 +717,6 @@ H5FL_blk_alloc(H5FL_blk_head_t *head, size_t size, unsigned clear)
/* Initialize the block allocated */
temp->size=size;
temp->next=NULL;
/* Set the return value to the block itself */
ret_value=((char *)temp)+sizeof(H5FL_blk_list_t);
@ -768,6 +756,7 @@ H5FL_blk_free(H5FL_blk_head_t *head, void *block)
{
H5FL_blk_node_t *free_list; /* The free list of nodes of correct size */
H5FL_blk_list_t *temp; /* Temp. ptr to the new free list node allocated */
size_t free_size; /* Size of the block freed */
FUNC_ENTER(H5FL_blk_free, NULL);
@ -781,6 +770,9 @@ H5FL_blk_free(H5FL_blk_head_t *head, void *block)
/* Get the pointer to the native block info header in front of the native block to free */
temp=(H5FL_blk_list_t *)((unsigned char *)block-sizeof(H5FL_blk_list_t));
/* Save the block's size for later */
free_size=temp->size;
/* check if there is a free list for native blocks of this size */
if((free_list=H5FL_blk_find_list(&(head->head),temp->size))==NULL) {
/* No free list available, create a new list node and insert it to the queue */
@ -789,33 +781,25 @@ H5FL_blk_free(H5FL_blk_head_t *head, void *block)
/* Prepend the free'd native block to the front of the free list */
if(free_list!=NULL) {
temp->next=free_list->list;
temp->next=free_list->list; /* Overwrites the size field in union */
free_list->list=temp;
} /* end if */
/* Increment the number of blocks on free list */
head->onlist++;
head->list_mem+=temp->size;
head->list_mem+=free_size;
/* Increment the amount of "block" freed memory globally */
H5FL_blk_gc_head.mem_freed+=temp->size;
H5FL_blk_gc_head.mem_freed+=free_size;
/* Check for exceeding free list memory use limits */
/* First check this particular list */
if(head->list_mem>H5FL_blk_lst_mem_lim) {
#ifdef QAK
printf("%s: temp->size=%u, head->name=%s, head->list_mem=%u, H5FL_blk_gc_head.mem_freed=%u, garbage collecting list\n",FUNC,(unsigned)temp->size,head->name,(unsigned)head->list_mem,(unsigned)H5FL_blk_gc_head.mem_freed);
#endif /* QAK */
if(head->list_mem>H5FL_blk_lst_mem_lim)
H5FL_blk_gc_list(head);
} /* end if */
/* Then check the global amount memory on block free lists */
if(H5FL_blk_gc_head.mem_freed>H5FL_blk_glb_mem_lim) {
#ifdef QAK
printf("%s: head->name=%s, garbage collecting all block lists\n",FUNC,head->name);
#endif /* QAK */
if(H5FL_blk_gc_head.mem_freed>H5FL_blk_glb_mem_lim)
H5FL_blk_gc();
} /* end if */
#endif /* NO_BLK_FREE_LISTS */
@ -916,10 +900,10 @@ H5FL_blk_gc_list(H5FL_blk_head_t *head)
/* Decrement the number of blocks & memory allocated from this PQ */
head->allocated--;
head->list_mem-=list->size;
head->list_mem-=head->head->size;
/* Decrement global count of free memory on "block" lists */
H5FL_blk_gc_head.mem_freed-=list->size;
H5FL_blk_gc_head.mem_freed-=head->head->size;
/* Free the block */
H5MM_xfree(list);
@ -1121,6 +1105,7 @@ H5FL_arr_free(H5FL_arr_head_t *head, void *obj)
{
H5FL_arr_node_t *temp; /* Temp. ptr to the new free list node allocated */
size_t mem_size; /* Size of memory being freed */
size_t free_nelem; /* Number of elements in node being free'd */
FUNC_ENTER (H5FL_arr_free, NULL);
@ -1142,20 +1127,23 @@ H5FL_arr_free(H5FL_arr_head_t *head, void *obj)
/* Get the pointer to the info header in front of the block to free */
temp=(H5FL_arr_node_t *)((unsigned char *)obj-sizeof(H5FL_arr_node_t));
/* Save the number of elements for later */
free_nelem=temp->nelem;
/* Double-check that there is enough room for arrays of this size */
assert((int)temp->nelem<=head->maxelem);
assert((int)free_nelem<=head->maxelem);
/* Link into the free list */
temp->next=head->u.list_arr[temp->nelem];
temp->next=head->u.list_arr[free_nelem];
/* Point free list at the node freed */
head->u.list_arr[temp->nelem]=temp;
head->u.list_arr[free_nelem]=temp;
/* Set the amount of memory being freed */
mem_size=temp->nelem*head->size;
mem_size=free_nelem*head->size;
/* Increment the number of blocks & memory used on free list */
head->onlist[temp->nelem]++;
head->onlist[free_nelem]++;
head->list_mem+=mem_size;
/* Increment the amount of "array" freed memory globally */
@ -1226,7 +1214,7 @@ H5FL_arr_alloc(H5FL_arr_head_t *head, size_t elem, unsigned clear)
/* Check for nodes available on the free list first */
if(head->u.list_arr[elem]!=NULL) {
/* Get a pointer to the block on the free list */
ret_value=((char *)(head->u.list_arr[elem]))+sizeof(H5FL_arr_node_t);
new_obj=head->u.list_arr[elem];
/* Remove node from free list */
head->u.list_arr[elem]=head->u.list_arr[elem]->next;
@ -1238,6 +1226,12 @@ H5FL_arr_alloc(H5FL_arr_head_t *head, size_t elem, unsigned clear)
/* Decrement the amount of global "array" free list memory in use */
H5FL_arr_gc_head.mem_freed-=mem_size;
/* Restore number of elements */
new_obj->nelem=elem;
/* Get the pointer to the data block */
ret_value=((char *)new_obj)+sizeof(H5FL_arr_node_t);
} /* end if */
/* Otherwise allocate a node */
else {
@ -1249,16 +1243,14 @@ H5FL_arr_alloc(H5FL_arr_head_t *head, size_t elem, unsigned clear)
/* Initialize the new object */
new_obj->nelem=elem;
new_obj->next=NULL;
/* Get a pointer to the new block */
ret_value=((char *)new_obj)+sizeof(H5FL_arr_node_t);
} /* end else */
/* Clear to zeros, if asked */
if(clear) {
if(clear)
HDmemset(ret_value,0,mem_size);
} /* end if */
} /* end if */
/* No fixed number of elements, use PQ routine */
else {

View File

@ -31,13 +31,6 @@
/* Data structure to store each block in free list */
typedef struct H5FL_reg_node_t {
struct H5FL_reg_node_t *next; /* Pointer to next block in free list */
#ifdef H5FL_DEBUG
unsigned inuse; /* Indicate when object is in use */
#endif /* H5FL_DEBUG */
union {
double unused1; /* Unused normally, just here for aligment */
haddr_t unused2; /* Unused normally, just here for aligment */
}align; /* Bogus union, just here to align following block */
} H5FL_reg_node_t;
/* Data structure for free list of blocks */
@ -73,14 +66,12 @@ typedef struct H5FL_reg_head_t {
* only support fixed sized types, like structs, etc..
*/
/* Data structure to store each block in free list */
typedef struct H5FL_blk_list_t {
/* Data structure to store information about each block allocated */
typedef union H5FL_blk_list_t {
size_t size; /* Size of the page */
struct H5FL_blk_list_t *next; /* Pointer to next block in free list */
union {
double unused1; /* Unused normally, just here for aligment */
haddr_t unused2; /* Unused normally, just here for aligment */
}align; /* Bogus union, just here to align following block */
union H5FL_blk_list_t *next; /* Pointer to next block in free list */
double unused1; /* Unused normally, just here for aligment */
haddr_t unused2; /* Unused normally, just here for aligment */
} H5FL_blk_list_t;
/* Data structure for priority queue node of block free lists */
@ -123,13 +114,11 @@ typedef struct H5FL_blk_head_t {
#define H5FL_BLK_REALLOC(t,blk,new_size) H5FL_blk_realloc(&(t##_pq),blk,new_size)
/* Data structure to store each array in free list */
typedef struct H5FL_arr_node_t {
struct H5FL_arr_node_t *next; /* Pointer to next block in free list */
typedef union H5FL_arr_node_t {
union H5FL_arr_node_t *next; /* Pointer to next block in free list */
size_t nelem; /* Number of elements in this array */
union {
double unused1; /* Unused normally, just here for aligment */
haddr_t unused2; /* Unused normally, just here for aligment */
}align; /* Bogus union, just here to align following block */
double unused1; /* Unused normally, just here for aligment */
haddr_t unused2; /* Unused normally, just here for aligment */
} H5FL_arr_node_t;
/* Data structure for free list of array blocks */