#include "utils/memutils.h"
#include "utils/resowner.h"
-/*
- * The size of the initial DSM segment that backs a dsa_area created by
- * dsa_create. After creating some number of segments of this size we'll
- * double this size, and so on. Larger segments may be created if necessary
- * to satisfy large requests.
- */
-#define DSA_INITIAL_SEGMENT_SIZE ((size_t) (1 * 1024 * 1024))
-
/*
* How many segments to create before we double the segment size. If this is
* low, then there is likely to be a lot of wasted space in the largest
*/
#define DSA_NUM_SEGMENTS_AT_EACH_SIZE 2
-/*
- * The number of bits used to represent the offset part of a dsa_pointer.
- * This controls the maximum size of a segment, the maximum possible
- * allocation size and also the maximum number of segments per area.
- */
-#if SIZEOF_DSA_POINTER == 4
-#define DSA_OFFSET_WIDTH 27 /* 32 segments of size up to 128MB */
-#else
-#define DSA_OFFSET_WIDTH 40 /* 1024 segments of size up to 1TB */
-#endif
-
/*
* The maximum number of DSM segments that an area can own, determined by
* the number of bits remaining (but capped at 1024).
/* The bitmask for extracting the offset from a dsa_pointer. */
#define DSA_OFFSET_BITMASK (((dsa_pointer) 1 << DSA_OFFSET_WIDTH) - 1)
-/* The maximum size of a DSM segment. */
-#define DSA_MAX_SEGMENT_SIZE ((size_t) 1 << DSA_OFFSET_WIDTH)
-
/* Number of pages (see FPM_PAGE_SIZE) per regular superblock. */
#define DSA_PAGES_PER_SUPERBLOCK 16
dsa_segment_index segment_bins[DSA_NUM_SEGMENT_BINS];
/* The object pools for each size class. */
dsa_area_pool pools[DSA_NUM_SIZE_CLASSES];
+ /* initial allocation segment size */
+ size_t init_segment_size;
+ /* maximum allocation segment size */
+ size_t max_segment_size;
/* The total size of all active segments. */
size_t total_segment_size;
/* The maximum total size of backing storage we are allowed. */
static dsa_area *create_internal(void *place, size_t size,
int tranche_id,
dsm_handle control_handle,
- dsm_segment *control_segment);
+ dsm_segment *control_segment,
+ size_t init_segment_size,
+ size_t max_segment_size);
static dsa_area *attach_internal(void *place, dsm_segment *segment,
dsa_handle handle);
static void check_for_freed_segments(dsa_area *area);
* we require the caller to provide one.
*/
dsa_area *
-dsa_create(int tranche_id)
+dsa_create_ext(int tranche_id, size_t init_segment_size, size_t max_segment_size)
{
dsm_segment *segment;
dsa_area *area;
* Create the DSM segment that will hold the shared control object and the
* first segment of usable space.
*/
- segment = dsm_create(DSA_INITIAL_SEGMENT_SIZE, 0);
+ segment = dsm_create(init_segment_size, 0);
/*
* All segments backing this area are pinned, so that DSA can explicitly
/* Create a new DSA area with the control object in this segment. */
area = create_internal(dsm_segment_address(segment),
- DSA_INITIAL_SEGMENT_SIZE,
+ init_segment_size,
tranche_id,
- dsm_segment_handle(segment), segment);
+ dsm_segment_handle(segment), segment,
+ init_segment_size, max_segment_size);
/* Clean up when the control segment detaches. */
on_dsm_detach(segment, &dsa_on_dsm_detach_release_in_place,
* See dsa_create() for a note about the tranche arguments.
*/
dsa_area *
-dsa_create_in_place(void *place, size_t size,
- int tranche_id, dsm_segment *segment)
+dsa_create_in_place_ext(void *place, size_t size,
+ int tranche_id, dsm_segment *segment,
+ size_t init_segment_size, size_t max_segment_size)
{
dsa_area *area;
area = create_internal(place, size, tranche_id,
- DSM_HANDLE_INVALID, NULL);
+ DSM_HANDLE_INVALID, NULL,
+ init_segment_size, max_segment_size);
/*
* Clean up when the control segment detaches, if a containing DSM segment
create_internal(void *place, size_t size,
int tranche_id,
dsm_handle control_handle,
- dsm_segment *control_segment)
+ dsm_segment *control_segment,
+ size_t init_segment_size, size_t max_segment_size)
{
dsa_area_control *control;
dsa_area *area;
size_t metadata_bytes;
int i;
+ /* Check the initial and maximum block sizes */
+ Assert(init_segment_size >= DSA_MIN_SEGMENT_SIZE);
+ Assert(max_segment_size >= init_segment_size);
+ Assert(max_segment_size <= DSA_MAX_SEGMENT_SIZE);
+
/* Sanity check on the space we have to work in. */
if (size < dsa_minimum_size())
elog(ERROR, "dsa_area space must be at least %zu, but %zu provided",
control->segment_header.prev = DSA_SEGMENT_INDEX_NONE;
control->segment_header.usable_pages = usable_pages;
control->segment_header.freed = false;
- control->segment_header.size = DSA_INITIAL_SEGMENT_SIZE;
+ control->segment_header.size = size;
control->handle = control_handle;
+ control->init_segment_size = init_segment_size;
+ control->max_segment_size = max_segment_size;
control->max_total_segment_size = (size_t) -1;
control->total_segment_size = size;
control->segment_handles[0] = control_handle;
* move to huge pages in the future. Then we work back to the number of
* pages we can fit.
*/
- total_size = DSA_INITIAL_SEGMENT_SIZE *
+ total_size = area->control->init_segment_size *
((size_t) 1 << (new_index / DSA_NUM_SEGMENTS_AT_EACH_SIZE));
- total_size = Min(total_size, DSA_MAX_SEGMENT_SIZE);
+ total_size = Min(total_size, area->control->max_segment_size);
total_size = Min(total_size,
area->control->max_total_segment_size -
area->control->total_segment_size);
/* A sentinel value for dsa_pointer used to indicate failure to allocate. */
#define InvalidDsaPointer ((dsa_pointer) 0)
+/*
+ * The number of bits used to represent the offset part of a dsa_pointer.
+ * This controls the maximum size of a segment, the maximum possible
+ * allocation size and also the maximum number of segments per area.
+ */
+#if SIZEOF_DSA_POINTER == 4
+#define DSA_OFFSET_WIDTH 27 /* 32 segments of size up to 128MB */
+#else
+#define DSA_OFFSET_WIDTH 40 /* 1024 segments of size up to 1TB */
+#endif
+
+/*
+ * The default size of the initial DSM segment that backs a dsa_area created
+ * by dsa_create. After creating some number of segments of the initial size
+ * we'll double this size, and so on. Larger segments may be created if
+ * necessary to satisfy large requests.
+ */
+#define DSA_DEFAULT_INIT_SEGMENT_SIZE ((size_t) (1 * 1024 * 1024))
+
+/* The minimum size of a DSM segment. */
+#define DSA_MIN_SEGMENT_SIZE ((size_t) (256 * 1024L))
+
+/* The maximum size of a DSM segment. */
+#define DSA_MAX_SEGMENT_SIZE ((size_t) 1 << DSA_OFFSET_WIDTH)
+
/* Check if a dsa_pointer value is valid. */
#define DsaPointerIsValid(x) ((x) != InvalidDsaPointer)
#define dsa_allocate0(area, size) \
dsa_allocate_extended(area, size, DSA_ALLOC_ZERO)
+/* Create dsa_area with default segment sizes */
+#define dsa_create(tranch_id) \
+ dsa_create_ext(tranch_id, DSA_DEFAULT_INIT_SEGMENT_SIZE, \
+ DSA_MAX_SEGMENT_SIZE)
+
+/* Create dsa_area with default segment sizes in an existing share memory space */
+#define dsa_create_in_place(place, size, tranch_id, segment) \
+ dsa_create_in_place_ext(place, size, tranch_id, segment, \
+ DSA_DEFAULT_INIT_SEGMENT_SIZE, \
+ DSA_MAX_SEGMENT_SIZE)
+
/*
* The type used for dsa_area handles. dsa_handle values can be shared with
* other processes, so that they can attach to them. This provides a way to
/* Sentinel value to use for invalid dsa_handles. */
#define DSA_HANDLE_INVALID ((dsa_handle) DSM_HANDLE_INVALID)
-
-extern dsa_area *dsa_create(int tranche_id);
-extern dsa_area *dsa_create_in_place(void *place, size_t size,
- int tranche_id, dsm_segment *segment);
+extern dsa_area *dsa_create_ext(int tranche_id, size_t init_segment_size,
+ size_t max_segment_size);
+extern dsa_area *dsa_create_in_place_ext(void *place, size_t size,
+ int tranche_id, dsm_segment *segment,
+ size_t init_segment_size,
+ size_t max_segment_size);
extern dsa_area *dsa_attach(dsa_handle handle);
extern dsa_area *dsa_attach_in_place(void *place, dsm_segment *segment);
extern void dsa_release_in_place(void *place);
projects / users / c2main / postgres.git / commitdiff