From 7107ed62f445c83a9c79b375158442f6b03f3ce6 Mon Sep 17 00:00:00 2001 From: Adam Dickmeiss Date: Fri, 1 Nov 1996 13:36:46 +0000 Subject: [PATCH] New element, max_blocks_mem, that control how many blocks of max size to store in memory during isc_merge. Function isc_merge now ignoreds delete/update of identical keys and the proper blocks are then non-dirty and not written in flush_blocks. --- isamc/isamc.c | 20 ++++-- isamc/merge.c | 216 +++++++++++++++++++++++++++++++-------------------------- 2 files changed, 133 insertions(+), 103 deletions(-) diff --git a/isamc/isamc.c b/isamc/isamc.c index 34595c3..6401c63 100644 --- a/isamc/isamc.c +++ b/isamc/isamc.c @@ -4,7 +4,13 @@ * Sebastian Hammer, Adam Dickmeiss * * $Log: isamc.c,v $ - * Revision 1.3 1996-11-01 08:59:14 adam + * Revision 1.4 1996-11-01 13:36:46 adam + * New element, max_blocks_mem, that control how many blocks of max size + * to store in memory during isc_merge. + * Function isc_merge now ignoreds delete/update of identical keys and + * the proper blocks are then non-dirty and not written in flush_blocks. + * + * Revision 1.3 1996/11/01 08:59:14 adam * First version of isc_merge that supports update/delete. * * Revision 1.2 1996/10/29 16:44:56 adam @@ -17,9 +23,8 @@ /* * TODO: - * small/empty blocks aren't handled in isc_merge. - * delete/update optimization of same key. - * implementation of isc_numkeys + * Reduction to lower categories in isc_merge + * Implementation of isc_numkeys */ #include #include @@ -49,6 +54,8 @@ ISAMC_M isc_getmethod (void) m->debug = 0; + m->max_blocks_mem = 10; + return m; } @@ -83,13 +90,18 @@ ISAMC isc_open (const char *name, int writeflag, ISAMC_M method) is->max_cat = --i; /* max_buf_size is the larget buffer to be used during merge */ max_buf_size = (1 + max_buf_size / filecat[i].bsize) * filecat[i].bsize; + if (max_buf_size < (1+is->method->max_blocks_mem) * filecat[i].bsize) + max_buf_size = (1+is->method->max_blocks_mem) * filecat[i].bsize; if (is->method->debug) logf (LOG_LOG, "isc: max_buf_size %d", max_buf_size); assert (is->no_files > 0); is->files = xmalloc (sizeof(*is->files)*is->no_files); if (writeflag) + { is->merge_buf = xmalloc (max_buf_size+128); + memset (is->merge_buf, 0, max_buf_size+128); + } else is->merge_buf = NULL; for (i = 0; ino_files; i++) diff --git a/isamc/merge.c b/isamc/merge.c index 77242ff..12334c6 100644 --- a/isamc/merge.c +++ b/isamc/merge.c @@ -4,7 +4,13 @@ * Sebastian Hammer, Adam Dickmeiss * * $Log: merge.c,v $ - * Revision 1.1 1996-11-01 08:59:15 adam + * Revision 1.2 1996-11-01 13:36:46 adam + * New element, max_blocks_mem, that control how many blocks of max size + * to store in memory during isc_merge. + * Function isc_merge now ignoreds delete/update of identical keys and + * the proper blocks are then non-dirty and not written in flush_blocks. + * + * Revision 1.1 1996/11/01 08:59:15 adam * First version of isc_merge that supports update/delete. * */ @@ -28,35 +34,36 @@ static void flush_blocks (ISAMC is, struct isc_merge_block *mb, int ptr, { int i; - for (i = 1; imethod->debug > 2) - logf (LOG_LOG, "isc: skip block %d %d", cat, mb[i-1].block); + logf (LOG_LOG, "isc: skip block %d %d", cat, mb[i].block); ++(is->files[cat].no_skip_writes); continue; } /* consider this block number */ - if (!mb[i-1].block) - mb[i-1].block = isc_alloc_block (is, cat); + + if (!mb[i].block) + mb[i].block = isc_alloc_block (is, cat); if (!*firstpos) - *firstpos = mb[i-1].block; + *firstpos = mb[i].block; /* consider next block pointer */ if (last && i == ptr-1) - mb[i].block = 0; - else if (!mb[i].block) - mb[i].block = isc_alloc_block (is, cat); + mb[i+1].block = 0; + else if (!mb[i+1].block) + mb[i+1].block = isc_alloc_block (is, cat); /* write block */ - assert (mb[i].offset > mb[i-1].offset); - isc_write_dblock (is, cat, mb[i-1].block, r_buf + mb[i-1].offset, - mb[i].block, mb[i].offset - mb[i-1].offset); + assert (mb[i+1].offset > mb[i].offset); + isc_write_dblock (is, cat, mb[i].block, r_buf + mb[i].offset, + mb[i+1].block, mb[i+1].offset - mb[i].offset); } } @@ -99,13 +106,59 @@ ISAMC_P isc_merge (ISAMC is, ISAMC_P ipos, ISAMC_I data) mb[ptr].block = pp->pos; /* is zero if no block on disk */ mb[ptr].dirty = 0; - mb[ptr++].offset = 0; + mb[ptr].offset = 0; while (i_more || f_more) { char *r_item = r_item_buf; int cmp; + if (f_more > 1) + { + /* block to block boundary in the original file. */ + f_more = 1; + if (cat == pp->cat) + { + /* the resulting output is of the same category as the + the original + */ + if (mb[ptr].offset == r_offset) + { + /* the resulting output block is empty. Delete + the original (if any) + */ + if (is->method->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; + } + else + { + /* indicate new boundary based on the original file */ + mb[++ptr].block = pp->pos; + mb[ptr].dirty = 0; + mb[ptr].offset = r_offset; +#if 0 + if (r_item && cat == is->max_cat) + { + /* We are dealing with block(s) of max size. Block(s) + will be flushed. Note: the block(s) are surely not + the last one(s). + */ + if (is->method->debug > 2) + logf (LOG_LOG, "isc: flush A %d sections", ptr); + flush_blocks (is, mb, ptr-1, r_buf, &firstpos, cat, 0); + ptr = 0; + mb[ptr].block = pp->pos; + mb[ptr].dirty = 0; + mb[ptr].offset = 0; + } +#endif + } + } + } if (!f_more) cmp = -1; else if (!i_more) @@ -123,7 +176,7 @@ ISAMC_P isc_merge (ISAMC is, ISAMC_P ipos, ISAMC_I data) /* it next input item the same as current except for the delete flag? */ cmp = (*is->method->compare_item)(i_item, f_item); - if (0 && !cmp && i_mode) + if (!cmp && i_mode) { /* yes! insert as if it was an insert only */ memcpy (r_item, i_item, i_item_ptr - i_item); @@ -135,7 +188,7 @@ ISAMC_P isc_merge (ISAMC is, ISAMC_P ipos, ISAMC_I data) { /* no! delete the item */ r_item = NULL; - mb[ptr-1].dirty = 1; + mb[ptr].dirty = 1; } } else @@ -167,56 +220,12 @@ ISAMC_P isc_merge (ISAMC is, ISAMC_P ipos, ISAMC_I data) abort (); } memcpy (r_item, i_item, i_item_ptr - i_item); - mb[ptr-1].dirty = 1; + mb[ptr].dirty = 1; /* move i */ i_item_ptr = i_item; i_more = (*data->read_item)(data->clientData, &i_item_ptr, &i_mode); } - if (f_more > 1) - { - /* block to block boundary in the original file. */ - f_more = 1; - if (cat == pp->cat) - { - /* the resulting output is of the same category as the - the original - */ - if (mb[ptr-1].offset == r_offset) - { - /* the resulting output block is empty. Delete - the original (if any) - */ - if (mb[ptr-1].block) - isc_release_block (is, pp->cat, mb[ptr-1].block); - mb[ptr-1].block = pp->pos; - 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++].offset = r_offset; -#if 0 - if (r_item && cat == is->max_cat) - { - /* We are dealing with block(s) of max size. Block(s) - will be flushed. Note: the block(s) are surely not - the last one(s). - */ - if (is->method->debug > 2) - logf (LOG_LOG, "isc: flush A %d sections", ptr-1); - flush_blocks (is, mb, ptr-1, r_buf, &firstpos, cat, 0); - ptr = 0; - mb[ptr].block = pp->pos; - mb[ptr].dirty = 0; - mb[ptr++].offset = 0; - } -#endif - } - } - } if (r_item) /* insert resulting item? */ { char *r_out_ptr = r_buf + r_offset; @@ -226,11 +235,11 @@ ISAMC_P isc_merge (ISAMC is, ISAMC_P ipos, ISAMC_I data) /* border set to initial fill or block size depending on whether we are creating a new one or updating and old one */ - if (mb[ptr-1].block) - border = mb[ptr-1].offset + is->method->filecat[cat].bsize + if (mb[ptr].block) + border = mb[ptr].offset + is->method->filecat[cat].bsize -ISAMC_BLOCK_OFFSET; else - border = mb[ptr-1].offset + is->method->filecat[cat].ifill + border = mb[ptr].offset + is->method->filecat[cat].ifill -ISAMC_BLOCK_OFFSET; (*is->method->code_item)(ISAMC_ENCODE, r_clientData, @@ -243,29 +252,37 @@ ISAMC_P isc_merge (ISAMC is, ISAMC_P ipos, ISAMC_I data) logf (LOG_LOG, "isc: border %d %d", ptr, border); /* Max size of current block category reached ... make new virtual block entry */ - mb[ptr].block = 0; + mb[++ptr].block = 0; mb[ptr].dirty = 1; - mb[ptr++].offset = r_offset; - if (cat == is->max_cat) + mb[ptr].offset = r_offset; + if (cat == is->max_cat && ptr >= is->method->max_blocks_mem) { /* We are dealing with block(s) of max size. Block(s) - will be flushed. Note: the block(s) are surely not - the last one(s). + except one will be flushed. Note: the block(s) are + surely not the last one(s). */ if (is->method->debug > 2) logf (LOG_LOG, "isc: flush B %d sections", ptr-1); - flush_blocks (is, mb, ptr, r_buf, &firstpos, cat, 0); + flush_blocks (is, mb, ptr-1, r_buf, &firstpos, cat, 0); + mb[0].block = mb[ptr-1].block; - ptr = 0; - mb[ptr].dirty = 1; - mb[ptr++].offset = 0; - memcpy (r_buf, r_buf + r_offset, new_offset - r_offset); - new_offset = (new_offset - r_offset); - } + mb[0].dirty = mb[ptr-1].dirty; + memcpy (r_buf, r_buf + mb[ptr-1].offset, + mb[ptr].offset - mb[ptr-1].offset); + mb[0].offset = 0; + + mb[1].block = mb[ptr].block; + mb[1].dirty = mb[0].dirty; + mb[1].offset = mb[ptr].offset - mb[ptr-1].offset; + memcpy (r_buf + mb[1].offset, r_buf + r_offset, + new_offset - r_offset); + new_offset = (new_offset - r_offset) + mb[1].offset; + ptr = 1; + } } r_offset = new_offset; } - if (cat < is->max_cat && ptr > is->method->filecat[cat].mblocks) + if (cat < is->max_cat && ptr >= is->method->filecat[cat].mblocks) { /* Max number blocks in current category reached -> must switch to next category (with larger block size) @@ -274,9 +291,9 @@ ISAMC_P isc_merge (ISAMC is, ISAMC_P ipos, ISAMC_I data) (is->files[cat].no_remap)++; /* delete all original block(s) read so far */ - for (i = 1; i < ptr; i++) - if (mb[i-1].block) - isc_release_block (is, pp->cat, mb[i-1].block); + for (i = 0; i < ptr; i++) + if (mb[i].block) + isc_release_block (is, pp->cat, mb[i].block); /* also delete all block to be read in the future */ pp->deleteFlag = 1; @@ -284,21 +301,20 @@ ISAMC_P isc_merge (ISAMC is, ISAMC_P ipos, ISAMC_I data) assert (mb[j].offset == 0); cat++; mb[j].dirty = 1; - mb[j++].block = 0; - for (i = 2; i < ptr; i++) + mb[j].block = 0; + for (i = 1; i < ptr; i++) { int border = is->method->filecat[cat].ifill - - ISAMC_BLOCK_OFFSET + mb[j-1].offset; + ISAMC_BLOCK_OFFSET + mb[j].offset; if (is->method->debug > 3) - logf (LOG_LOG, "isc: remap %d border=%d", i-1, border); - if (mb[i].offset > border && mb[i-1].offset <= border) + 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) - logf (LOG_LOG, "isc: to %d %d", j, mb[i-1].offset); - mb[j].dirty = 1; + logf (LOG_LOG, "isc: to %d %d", j, mb[i].offset); + mb[++j].dirty = 1; mb[j].block = 0; - mb[j++].offset = mb[i-1].offset; - assert (j <= i); + mb[j].offset = mb[i].offset; } } if (is->method->debug > 2) @@ -307,24 +323,26 @@ ISAMC_P isc_merge (ISAMC is, ISAMC_P ipos, ISAMC_I data) ptr = j; } } - if (mb[ptr-1].offset < r_offset) + if (mb[ptr].offset < r_offset) { /* make the final boundary offset */ - mb[ptr].dirty = 1; /* ignored by flush_blocks */ + mb[++ptr].dirty = 1; /* ignored by flush_blocks */ mb[ptr].block = 0; /* ignored by flush_blocks */ - mb[ptr++].offset = r_offset; + mb[ptr].offset = r_offset; } else { /* empty output. Release last block if any */ - if (cat == pp->cat && mb[ptr-1].block) + if (cat == pp->cat && mb[ptr].block) { - isc_release_block (is, pp->cat, mb[ptr-1].block); - mb[ptr-1].block = 0; - mb[ptr-1].dirty = 1; + if (is->method->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 (is->method->debug > 2) - logf (LOG_LOG, "isc: flush C, %d sections", ptr-1); + logf (LOG_LOG, "isc: flush C, %d sections", ptr); /* flush rest of block(s) in r_buf */ flush_blocks (is, mb, ptr, r_buf, &firstpos, cat, 1); -- 1.7.10.4