/*
- * Copyright (c) 1996, Index Data.
+ * Copyright (c) 1996-1998, Index Data.
* See the file LICENSE for details.
* Sebastian Hammer, Adam Dickmeiss
*
* $Log: merge.c,v $
- * Revision 1.4 1996-11-08 11:15:31 adam
+ * Revision 1.11 1999-05-26 07:49:14 adam
+ * C++ compilation.
+ *
+ * Revision 1.10 1998/03/19 12:22:09 adam
+ * Minor change.
+ *
+ * Revision 1.9 1998/03/19 10:04:38 adam
+ * Minor changes.
+ *
+ * Revision 1.8 1998/03/18 09:23:55 adam
+ * Blocks are stored in chunks on free list - up to factor 2 in speed.
+ * Fixed bug that could occur in block category rearrangemen.
+ *
+ * Revision 1.7 1998/03/11 11:18:18 adam
+ * Changed the isc_merge to take into account the mfill (minimum-fill).
+ *
+ * Revision 1.6 1998/03/06 13:54:03 adam
+ * Fixed two nasty bugs in isc_merge.
+ *
+ * Revision 1.5 1997/02/12 20:42:43 adam
+ * Bug fix: during isc_merge operations, some pages weren't marked dirty
+ * even though they should be. At this point the merge operation marks
+ * a page dirty if the previous page changed at all. A better approach is
+ * to mark it dirty if the last key written changed in previous page.
+ *
+ * Revision 1.4 1996/11/08 11:15:31 adam
* Number of keys in chain are stored in first block and the function
* to retrieve this information, isc_pp_num is implemented.
*
int dirty; /* block is different from that on file */
};
+static void opt_blocks (ISAMC is, struct isc_merge_block *mb, int ptr,
+ int last)
+{
+ int i, no_dirty = 0;
+ for (i = 0; i<ptr; i++)
+ if (mb[i].dirty)
+ no_dirty++;
+ if (no_dirty*4 < ptr*3)
+ return;
+ /* bubble-sort it */
+ for (i = 0; i<ptr; i++)
+ {
+ int tmp, j, j_min = -1;
+ for (j = i; j<ptr; j++)
+ {
+ if (j_min < 0 || mb[j_min].block > mb[j].block)
+ j_min = j;
+ }
+ assert (j_min >= 0);
+ tmp = mb[j_min].block;
+ mb[j_min].block = mb[i].block;
+ mb[i].block = tmp;
+ mb[i].dirty = 1;
+ }
+ if (!last)
+ mb[i].dirty = 1;
+}
+
static void flush_blocks (ISAMC is, struct isc_merge_block *mb, int ptr,
char *r_buf, int *firstpos, int cat, int last,
int *numkeys)
for (i = 0; i<ptr; i++)
{
- unsigned short ssize;
+ /* consider this block number */
+ if (!mb[i].block)
+ {
+ mb[i].block = isc_alloc_block (is, cat);
+ mb[i].dirty = 1;
+ }
+
+ /* consider next block pointer */
+ if (last && i == ptr-1)
+ mb[i+1].block = 0;
+ else if (!mb[i+1].block)
+ {
+ mb[i+1].block = isc_alloc_block (is, cat);
+ mb[i+1].dirty = 1;
+ mb[i].dirty = 1;
+ }
+ }
+
+ for (i = 0; i<ptr; i++)
+ {
char *src;
+ ISAMC_BLOCK_SIZE ssize = mb[i+1].offset - mb[i].offset;
+
+ assert (ssize);
/* skip rest if not dirty */
if (!mb[i].dirty)
if (!*firstpos)
*firstpos = mb[i].block;
if (is->method->debug > 2)
- logf (LOG_LOG, "isc: skip block %d %d", cat, mb[i].block);
+ logf (LOG_LOG, "isc: skip ptr=%d size=%d %d %d",
+ i, ssize, cat, mb[i].block);
++(is->files[cat].no_skip_writes);
continue;
}
- /* consider this block number */
-
- if (!mb[i].block)
- mb[i].block = isc_alloc_block (is, cat);
-
- /* consider next block pointer */
- if (last && i == ptr-1)
- mb[i+1].block = 0;
- else if (!mb[i+1].block)
- mb[i+1].block = isc_alloc_block (is, cat);
-
/* write block */
- ssize = mb[i+1].offset - mb[i].offset;
- assert (ssize);
if (!*firstpos)
{
memcpy (src+sizeof(int)+sizeof(ssize), numkeys,
sizeof(*numkeys));
if (is->method->debug > 2)
- logf (LOG_LOG, "isc: flush numk=%d size=%d nextpos=%d",
- *numkeys, (int) ssize, mb[i+1].block);
+ logf (LOG_LOG, "isc: flush ptr=%d numk=%d size=%d nextpos=%d",
+ i, *numkeys, (int) ssize, mb[i+1].block);
}
else
{
src = r_buf + mb[i].offset - ISAMC_BLOCK_OFFSET_N;
ssize += ISAMC_BLOCK_OFFSET_N;
if (is->method->debug > 2)
- logf (LOG_LOG, "isc: flush size=%d nextpos=%d",
- (int) ssize, mb[i+1].block);
+ logf (LOG_LOG, "isc: flush ptr=%d size=%d nextpos=%d",
+ i, (int) ssize, mb[i+1].block);
}
memcpy (src, &mb[i+1].block, sizeof(int));
memcpy (src+sizeof(int), &ssize, sizeof(ssize));
ISAMC_PP pp;
char f_item[128], *f_item_ptr;
int f_more;
+ int last_dirty = 0;
+ int debug = is->method->debug;
struct isc_merge_block mb[200];
f_more = 1;
cat = pp->cat;
- if (is->method->debug > 1)
+ if (debug > 1)
logf (LOG_LOG, "isc: isc_merge begin %d %d", cat, pp->pos);
/* read first item from i */
{
/* the resulting output is of the same category as the
the original
- */
- if (mb[ptr].offset == r_offset)
+ */
+ if (r_offset <= mb[ptr].offset +is->method->filecat[cat].mfill)
{
- /* the resulting output block is empty. Delete
+ /* the resulting output block is too small/empty. Delete
the original (if any)
- */
- if (is->method->debug > 3)
+ */
+ if (debug > 3)
logf (LOG_LOG, "isc: release A");
if (mb[ptr].block)
isc_release_block (is, pp->cat, mb[ptr].block);
mb[ptr].block = pp->pos;
- mb[ptr].dirty = 0;
+ if (!mb[ptr].dirty)
+ mb[ptr].dirty = 1;
+ if (ptr > 0)
+ mb[ptr-1].dirty = 1;
}
else
{
/* indicate new boundary based on the original file */
mb[++ptr].block = pp->pos;
- mb[ptr].dirty = 0;
+ mb[ptr].dirty = last_dirty;
mb[ptr].offset = r_offset;
+ if (debug > 3)
+ logf (LOG_LOG, "isc: bound ptr=%d,offset=%d",
+ ptr, r_offset);
if (cat==is->max_cat && ptr >= is->method->max_blocks_mem)
{
/* We are dealing with block(s) of max size. Block(s)
except 1 will be flushed.
*/
- if (is->method->debug > 2)
+ if (debug > 2)
logf (LOG_LOG, "isc: flush A %d sections", ptr);
flush_blocks (is, mb, ptr-1, r_buf, &firstpos, cat,
- 0, &numKeys);
-
+ 0, &pp->numKeys);
mb[0].block = mb[ptr-1].block;
mb[0].dirty = mb[ptr-1].dirty;
memcpy (r_buf, r_buf + mb[ptr-1].offset,
}
border = get_border (is, mb, ptr, cat, firstpos);
}
+ last_dirty = 0;
if (!f_more)
cmp = -1;
else if (!i_more)
/* is next input item the same as current except
for the delete flag? */
cmp = (*is->method->compare_item)(i_item, f_item);
- if (!cmp && i_mode)
+ if (!cmp && i_mode) /* delete/insert nop? */
{
/* yes! insert as if it was an insert only */
memcpy (r_item, i_item, i_item_ptr - i_item);
{
/* no! delete the item */
r_item = NULL;
- mb[ptr].dirty = 1;
+ last_dirty = 1;
+ mb[ptr].dirty = 2;
}
}
else
abort ();
}
memcpy (r_item, i_item, i_item_ptr - i_item);
- mb[ptr].dirty = 1;
+ mb[ptr].dirty = 2;
+ last_dirty = 1;
/* move i */
i_item_ptr = i_item;
i_more = (*data->read_item)(data->clientData, &i_item_ptr,
if (border < new_offset && border >= r_offset)
{
- if (is->method->debug > 2)
+ if (debug > 2)
logf (LOG_LOG, "isc: border %d %d", ptr, border);
/* Max size of current block category reached ...
make new virtual block entry */
except one will be flushed. Note: the block(s) are
surely not the last one(s).
*/
- if (is->method->debug > 2)
+ if (debug > 2)
logf (LOG_LOG, "isc: flush B %d sections", ptr-1);
flush_blocks (is, mb, ptr-1, r_buf, &firstpos, cat,
- 0, &numKeys);
-
+ 0, &pp->numKeys);
mb[0].block = mb[ptr-1].block;
mb[0].dirty = mb[ptr-1].dirty;
memcpy (r_buf, r_buf + mb[ptr-1].offset,
cat++;
mb[j].dirty = 1;
mb[j].block = 0;
+ mb[ptr].offset = r_offset;
for (i = 1; i < ptr; i++)
{
int border = is->method->filecat[cat].ifill -
ISAMC_BLOCK_OFFSET_1 + mb[j].offset;
- if (is->method->debug > 3)
+ if (debug > 3)
logf (LOG_LOG, "isc: remap %d border=%d", i, border);
if (mb[i+1].offset > border && mb[i].offset <= border)
{
- if (is->method->debug > 3)
+ if (debug > 3)
logf (LOG_LOG, "isc: to %d %d", j, mb[i].offset);
mb[++j].dirty = 1;
mb[j].block = 0;
mb[j].offset = mb[i].offset;
}
}
- if (is->method->debug > 2)
+ if (debug > 2)
logf (LOG_LOG, "isc: remap from %d to %d sections to cat %d",
ptr, j, cat);
ptr = j;
border = get_border (is, mb, ptr, cat, firstpos);
+ if (debug > 3)
+ logf (LOG_LOG, "isc: border=%d r_offset=%d", border, r_offset);
}
}
if (mb[ptr].offset < r_offset)
{ /* empty output. Release last block if any */
if (cat == pp->cat && mb[ptr].block)
{
- if (is->method->debug > 3)
+ if (debug > 3)
logf (LOG_LOG, "isc: release C");
isc_release_block (is, pp->cat, mb[ptr].block);
mb[ptr].block = 0;
- mb[ptr].dirty = 1;
+ if (ptr > 0)
+ mb[ptr-1].dirty = 1;
}
}
- if (is->method->debug > 2)
+ if (debug > 2)
logf (LOG_LOG, "isc: flush C, %d sections", ptr);
if (firstpos)
has changed */
if (numKeys != isc_pp_num (pp))
{
- if (is->method->debug > 2)
+ if (debug > 2)
logf (LOG_LOG, "isc: patch num keys firstpos=%d num=%d",
firstpos, numKeys);
bf_write (is->files[cat].bf, firstpos, ISAMC_BLOCK_OFFSET_N,
(*is->method->code_stop)(ISAMC_ENCODE, r_clientData);
if (!firstpos)
cat = 0;
- if (is->method->debug > 1)
+ if (debug > 1)
logf (LOG_LOG, "isc: isc_merge return %d %d", cat, firstpos);
isc_pp_close (pp);
return cat + firstpos * 8;
projects / idzebra-moved-to-github.git / blobdiff