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authorAlbert Cheng <acheng@hdfgroup.org>2001-05-01 19:07:47 (GMT)
committerAlbert Cheng <acheng@hdfgroup.org>2001-05-01 19:07:47 (GMT)
commit570a182e6d03e12f5a02ccd5a6f10c555cbe2276 (patch)
tree02649abf6ae64ab3497cd2ca1a3b63884b403467 /src/H5FD.c
parent881a560e0338fd8e7700cfaa57bdcf8718b35c14 (diff)
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[svn-r3881] Purpose:
Feature Description: The allocation by alignment (H5Pset_alignment) feature code somehow got dropped in some 1.3.x version. Solution: Re-implemented it with "new and improved" algorithm. It keeps track of "wasted" file-fragment in the free-list too. Platforms tested: modi4(parallel).
Diffstat (limited to 'src/H5FD.c')
-rw-r--r--src/H5FD.c199
1 files changed, 171 insertions, 28 deletions
diff --git a/src/H5FD.c b/src/H5FD.c
index d182cc4..ac48d33 100644
--- a/src/H5FD.c
+++ b/src/H5FD.c
@@ -789,8 +789,10 @@ H5FD_open(const char *name, unsigned flags, hid_t fapl_id, haddr_t maxaddr)
file->cls = driver;
file->maxaddr = maxaddr;
HDmemset(file->fl, 0, sizeof(file->fl));
- file->def_meta_block_size = fapl->meta_block_size;
+ file->def_meta_block_size = fapl->meta_block_size;
file->accum_loc = HADDR_UNDEF;
+ file->threshold = fapl->threshold;
+ file->alignment = fapl->alignment;
/* Retrieve the VFL driver feature flags */
if (H5FD_query(file, &(file->feature_flags))<0)
@@ -1155,6 +1157,8 @@ H5FDalloc(H5FD_t *file, H5FD_mem_t type, hsize_t size)
* Wednesday, August 4, 1999
*
* Modifications:
+ * Albert Cheng, 2001/05/01
+ * Implement the allocation by alignment/threshold.
*
*-------------------------------------------------------------------------
*/
@@ -1171,6 +1175,12 @@ H5FD_alloc(H5FD_t *file, H5FD_mem_t type, hsize_t size)
assert(type>=0 && type<H5FD_MEM_NTYPES);
assert(size>0);
+#ifdef H5F_DEBUG
+ if (H5DEBUG(F)) {
+ fprintf(H5DEBUG(F), "%s: alignment=%ld, threshold=%ld, size=%ld\n",
+ FUNC, file->alignment, file->threshold, size);
+ }
+#endif
/* Map the allocation request to a free list */
if (H5FD_MEM_DEFAULT==file->cls->fl_map[type]) {
mapped_type = type;
@@ -1179,41 +1189,134 @@ H5FD_alloc(H5FD_t *file, H5FD_mem_t type, hsize_t size)
}
/*
- * Try to satisfy the request from the free list. First try to find an
- * exact match, otherwise use the best match. Only perform the search if
- * the free list has the potential of satisfying the request.
+ * Try to satisfy the request from the free list. Only perform the search
+ * if the free list has the potential of satisfying the request.
+ * Here, aligned requests are requests that are >= threshold and
+ * alignment > 1.
+ * For non-aligned request, first try to find an exact match, otherwise
+ * use the best match which is the smallest size that meets the requested
+ * size.
+ * For aligned address request, find a block in the following order
+ * of preferences:
+ * 1. block address is aligned and exact match in size;
+ * 2. block address is aligned with smallest size > requested size;
+ * 3. block address is not aligned with smallest size >= requested size.
*/
if (mapped_type>=0 && (0==file->maxsize || size<=file->maxsize)) {
H5FD_free_t *prev=NULL, *best=NULL;
H5FD_free_t *cur = file->fl[mapped_type];
+ int found_aligned = 0;
+ int need_aligned;
+ hsize_t head;
+ need_aligned = file->alignment > 1 && size >= file->threshold;
while (cur) {
file->maxsize = MAX(file->maxsize, cur->size);
- if (cur->size==size) {
- ret_value = cur->addr;
- if (prev)
- prev->next = cur->next;
- else
- file->fl[mapped_type] = cur->next;
- H5MM_xfree(cur);
- if (size==file->maxsize)
- file->maxsize=0; /*unknown*/
- HRETURN(ret_value);
- } else if (cur->size>size && (!best || cur->size<best->size)) {
- best = cur;
- }
+ if (need_aligned){
+ if ((head = cur->addr % file->alignment) == 0){
+ /* got aligned address*/
+ if (cur->size==size){
+ /* exact match */
+ ret_value = cur->addr;
+ if (prev)
+ prev->next = cur->next;
+ else
+ file->fl[mapped_type] = cur->next;
+ H5MM_xfree(cur);
+ if (size==file->maxsize)
+ file->maxsize=0; /*unknown*/
+ HRETURN(ret_value);
+ }
+ if (cur->size>size){
+ if (!best || !found_aligned || cur->size<best->size) {
+ best = cur;
+ found_aligned = 1;
+ }
+ }
+ }else{
+ /* non-aligned address.
+ * check to see if this block is big enough to skip
+ * to the next aligned address and is still big enough
+ * for the requested size.
+ * the extra cur->size>head is for preventing unsigned
+ * underflow.
+ * (this can be improved by checking for an exact match
+ * after excluding the head. Such match is as good as
+ * the found_aligned case above.)
+ */
+ head = file->alignment - head; /* actual head size */
+ if (!found_aligned &&
+ cur->size > head && cur->size-head >= size &&
+ (!best || cur->size < best->size)){
+ best =cur;
+ }
+ }
+ }else{
+ /* !need_aligned */
+ if (cur->size==size) {
+ ret_value = cur->addr;
+ if (prev)
+ prev->next = cur->next;
+ else
+ file->fl[mapped_type] = cur->next;
+ H5MM_xfree(cur);
+ if (size==file->maxsize)
+ file->maxsize=0; /*unknown*/
+ HRETURN(ret_value);
+ } else if (cur->size>size && (!best || cur->size<best->size)) {
+ best = cur;
+ }
+ }
prev = cur;
cur = cur->next;
}
if (best) {
- if (best->size==file->maxsize)
- file->maxsize=0; /*unknown*/
- ret_value = best->addr;
- best->addr += size;
- best->size -= size;
- HRETURN(ret_value);
+ if (best->size==file->maxsize)
+ file->maxsize=0; /*unknown*/
+ if (!need_aligned || found_aligned){
+ /* free only tail */
+ ret_value = best->addr;
+ best->addr += size;
+ best->size -= size;
+ HRETURN(ret_value);
+ }else{
+ /* split into 3 pieces. Keep the the head and tail in */
+ /* the freelist. */
+ H5FD_free_t *tmp = H5MM_malloc(sizeof(H5FD_free_t));
+
+ head = file->alignment - (best->addr % file->alignment);
+ ret_value = best->addr + head;
+#ifdef H5F_DEBUG
+ if (H5DEBUG(F)) {
+ fprintf(H5DEBUG(F),
+ "%s: 3 pieces, begin best->addr=%ld, best->size=%ld, "
+ "head=%ld, size=%ld\n",
+ FUNC, best->addr, best->size, head, size);
+ }
+#endif
+ assert(tmp); /* bark in debug mode */
+ if (tmp){
+ if (tmp->size = best->size - head - size){
+ tmp->addr = best->addr + head + size;
+ tmp->next = best->next;
+ best->next = tmp;
+ }else{
+ /* no tail piece */
+ H5MM_xfree(tmp);
+ }
+ }else{
+ /* cannot keep the tail piece. leak file memory. */
+ }
+ best->size = head;
+ HRETURN(ret_value);
+ }
}
}
+#ifdef H5F_DEBUG
+ if (H5DEBUG(F)) {
+ fprintf(H5DEBUG(F), "%s: Could not allocate from freelists\n", FUNC);
+ }
+#endif
/*
* If the metadata aggregation feature is enabled for this VFL driver,
@@ -1275,6 +1378,8 @@ H5FD_alloc(H5FD_t *file, H5FD_mem_t type, hsize_t size)
* Friday, August 25, 2000
*
* Modifications:
+ * Albert Cheng, 2001/05/01
+ * Implement the allocation by alignment/threshold.
*
*-------------------------------------------------------------------------
*/
@@ -1301,7 +1406,35 @@ H5FD_real_alloc(H5FD_t *file, H5FD_mem_t type, hsize_t size)
"driver allocation request failed");
}
} else {
- haddr_t eoa = (file->cls->get_eoa)(file);
+ hsize_t wasted, tmpsize;
+ haddr_t oldeoa;
+ haddr_t eoa = (file->cls->get_eoa)(file);
+
+#ifdef H5F_DEBUG
+ if (file->alignment * file->threshold != 1 && H5DEBUG(F)) {
+ fprintf(H5DEBUG(F),
+ "%s: alignment=%ld, threshold=%ld, size=%ld, Begin eoa=%ld\n",
+ FUNC, file->alignment, file->threshold, size, eoa);
+ }
+#endif
+ /* wasted is 0 if not exceeding threshold or eoa happens to be aligned*/
+ wasted = (size>=file->threshold) ? (eoa % file->alignment) : 0;
+ if (wasted){
+ wasted = file->alignment - wasted; /* actual waste */
+ oldeoa = eoa; /* save it for later freeing */
+ /* advance eoa to the next alignment by allocating the wasted */
+ if (H5F_addr_overflow(eoa, wasted) || eoa+wasted>file->maxaddr) {
+ HRETURN_ERROR(H5E_VFL, H5E_NOSPACE, HADDR_UNDEF,
+ "file allocation request failed");
+ }
+ eoa += wasted;
+ if ((file->cls->set_eoa)(file, eoa)<0) {
+ HRETURN_ERROR(H5E_VFL, H5E_NOSPACE, HADDR_UNDEF,
+ "file allocation request failed");
+ }
+ }
+
+ /* allocate the aligned memory */
if (H5F_addr_overflow(eoa, size) || eoa+size>file->maxaddr) {
HRETURN_ERROR(H5E_VFL, H5E_NOSPACE, HADDR_UNDEF,
"file allocation request failed");
@@ -1312,6 +1445,18 @@ H5FD_real_alloc(H5FD_t *file, H5FD_mem_t type, hsize_t size)
HRETURN_ERROR(H5E_VFL, H5E_NOSPACE, HADDR_UNDEF,
"file allocation request failed");
}
+
+ /* Free the wasted memory */
+ if (wasted)
+ H5FDfree(file, type, oldeoa, wasted);
+
+#ifdef H5F_DEBUG
+ if (file->alignment * file->threshold != 1 && H5DEBUG(F)) {
+ fprintf(H5DEBUG(F),
+ "%s: ret_value=%ld, wasted=%ld, Ended eoa=%ld\n",
+ FUNC, ret_value, wasted, eoa);
+ }
+#endif
}
FUNC_LEAVE(ret_value);
@@ -1414,9 +1559,7 @@ H5FD_free(H5FD_t *file, H5FD_mem_t type, haddr_t addr, hsize_t size)
cur->size = size;
cur->next = file->fl[mapped_type];
file->fl[mapped_type] = cur;
- if (file->maxsize && size>file->maxsize) {
- file->maxsize = size;
- }
+ file->maxsize = MAX(file->maxsize, size);
} else if (file->cls->free) {
if ((file->cls->free)(file, type, addr, size)<0) {
HRETURN_ERROR(H5E_VFL, H5E_CANTINIT, FAIL,
@@ -1526,7 +1669,7 @@ H5FD_realloc(H5FD_t *file, H5FD_mem_t type, haddr_t old_addr, hsize_t old_size,
"memory allocation failed");
}
if (H5FDread(file, type, H5P_DEFAULT, old_addr, old_size, buf)<0 ||
- H5FDwrite(file, type, H5P_DEFAULT, new_addr, old_size, buf)) {
+ H5FDwrite(file, type, H5P_DEFAULT, new_addr, old_size, buf)<0) {
H5FDfree(file, type, new_addr, new_size);
H5MM_xfree(buf);
HRETURN_ERROR(H5E_FILE, H5E_READERROR, HADDR_UNDEF,