branches/zip: On compressed pages, always update the insert buffer bitmap.

Do not assume anything about the contents of the bitmap.

ibuf_update_free_bits_low(): Use this function only for uncompressed pages.
Remove the parameter zip_size.  This function avoids latching the bitmap page
and updating the bitmap when the bits do not change.

ibuf_update_free_bits_zip(): New function based on ibuf_update_free_bits_low(),
for use on compressed pages.  Remove the parameter max_insert_size that
was used for computing the before image of the free bits.  Always update the
bitmap.

ibuf_index_page_calc_free_zip(): New function, factored out from
ibuf_index_page_calc_free().

ibuf_update_free_bits_if_full(): Document that this function must only be
invoked on uncompressed pages.  Add a debug assertion about this.

btr/btr0cur.c

@@ -1014,7 +1014,6 @@ btr_cur_optimistic_insert(
 	buf_block_t*	block;
 	page_t*		page;
 	ulint		max_size;
-	ulint		max_size_zip	= 0;
 	rec_t*		dummy_rec;
 	ibool		leaf;
 	ibool		reorg;
@@ -1046,19 +1045,6 @@ btr_cur_optimistic_insert(
 	max_size = page_get_max_insert_size_after_reorganize(page, 1);
 	leaf = page_is_leaf(page);
 
-	/* If necessary for updating the insert buffer bitmap,
-	calculate the current maximum insert size on a compressed page. */
-	if (zip_size && UNIV_LIKELY(leaf) && !dict_index_is_clust(index)) {
-		const page_zip_des_t*	page_zip
-			= buf_block_get_page_zip(block);
-		lint			zip_max
-			= page_zip_max_ins_size(page_zip, FALSE);
-
-		if (zip_max >= 0 && max_size > (ulint) zip_max) {
-			max_size_zip = (ulint) zip_max;
-		}
-	}
-
 	/* Calculate the record size when entry is converted to a record */
 	rec_size = rec_get_converted_size(index, entry, n_ext);
 
@@ -1206,8 +1192,7 @@ fail_err:
 
 		if (zip_size) {
 			/* Update the bits in the same mini-transaction. */
-			ibuf_update_free_bits_low(zip_size, block,
-						  max_size_zip, mtr);
+			ibuf_update_free_bits_zip(block, mtr);
 		} else {
 			/* Decrement the bits in a separate
 			mini-transaction. */
@@ -1752,8 +1737,7 @@ btr_cur_update_in_place(
 	if (page_zip && !dict_index_is_clust(index)
 	    && page_is_leaf(buf_block_get_frame(block))) {
 		/* Update the free bits in the insert buffer. */
-		ibuf_update_free_bits_low(buf_block_get_zip_size(block),
-					  block, UNIV_PAGE_SIZE, mtr);
+		ibuf_update_free_bits_zip(block, mtr);
 	}
 
 	btr_cur_update_in_place_log(flags, rec, index, update,
@@ -1956,8 +1940,7 @@ err_exit:
 	if (page_zip && !dict_index_is_clust(index)
 	    && page_is_leaf(page)) {
 		/* Update the free bits in the insert buffer. */
-		ibuf_update_free_bits_low(buf_block_get_zip_size(block), block,
-					  UNIV_PAGE_SIZE, mtr);
+		ibuf_update_free_bits_zip(block, mtr);
 	}
 
 	if (!rec_get_deleted_flag(rec, page_is_comp(page))) {
@@ -2224,9 +2207,7 @@ btr_cur_pessimistic_update(
 		if (page_zip && !dict_index_is_clust(index)
 		    && page_is_leaf(page)) {
 			/* Update the free bits in the insert buffer. */
-			ibuf_update_free_bits_low(
-				buf_block_get_zip_size(block), block,
-				UNIV_PAGE_SIZE, mtr);
+			ibuf_update_free_bits_zip(block, mtr);
 		}
 
 		err = DB_SUCCESS;
@@ -2708,7 +2689,6 @@ btr_cur_optimistic_delete(
 	mtr_t*		mtr)	/* in: mtr */
 {
 	buf_block_t*	block;
-	ulint		max_ins_size;
 	rec_t*		rec;
 	mem_heap_t*	heap		= NULL;
 	ulint		offsets_[REC_OFFS_NORMAL_SIZE];
@@ -2736,24 +2716,15 @@ btr_cur_optimistic_delete(
 
 		page_t*		page	= buf_block_get_frame(block);
 		page_zip_des_t*	page_zip= buf_block_get_page_zip(block);
-		ulint		zip_size= buf_block_get_zip_size(block);
+		ulint		max_ins	= 0;
 
 		lock_update_delete(block, rec);
 
 		btr_search_update_hash_on_delete(cursor);
 
-		max_ins_size = page_get_max_insert_size_after_reorganize(
-			page, 1);
-		if (zip_size) {
-			lint	zip_max_ins = page_zip_max_ins_size(
-				page_zip, FALSE/* not clustered */);
-
-			if (UNIV_UNLIKELY(zip_max_ins < 0)) {
-				max_ins_size = 0;
-			} else if (UNIV_LIKELY
-				   (max_ins_size > (ulint) zip_max_ins)) {
-				max_ins_size = (ulint) zip_max_ins;
-			}
+		if (!page_zip) {
+			max_ins = page_get_max_insert_size_after_reorganize(
+				page, 1);
 		}
 #ifdef UNIV_ZIP_DEBUG
 		ut_a(!page_zip || page_zip_validate(page_zip, page));
@@ -2764,10 +2735,15 @@ btr_cur_optimistic_delete(
 		ut_a(!page_zip || page_zip_validate(page_zip, page));
 #endif /* UNIV_ZIP_DEBUG */
 
-		if (!dict_index_is_clust(cursor->index)
-		    && page_is_leaf(page)) {
-			ibuf_update_free_bits_low(zip_size, block,
-						  max_ins_size, mtr);
+		if (dict_index_is_clust(cursor->index)
+		    || !page_is_leaf(page)) {
+			/* The insert buffer does not handle
+			inserts to clustered indexes or to non-leaf
+			pages of secondary index B-trees. */
+		} else if (page_zip) {
+			ibuf_update_free_bits_zip(block, mtr);
+		} else {
+			ibuf_update_free_bits_low(block, max_ins, mtr);
 		}
 	}
 

ibuf/ibuf0ibuf.c

@@ -790,13 +790,13 @@ UNIV_INLINE
 void
 ibuf_set_free_bits_low(
 /*===================*/
-	ulint		zip_size,/* in: compressed page size in bytes;
-				0 for uncompressed pages */
-	buf_block_t*	block,	/* in: index page; free bits are set if
-				the index is non-clustered and page
-				level is 0 */
-	ulint		val,	/* in: value to set: < 4 */
-	mtr_t*		mtr)	/* in: mtr */
+	ulint			zip_size,/* in: compressed page size in bytes;
+					0 for uncompressed pages */
+	const buf_block_t*	block,	/* in: index page; free bits are set if
+					the index is non-clustered and page
+					level is 0 */
+	ulint			val,	/* in: value to set: < 4 */
+	mtr_t*			mtr)	/* in/out: mtr */
 {
 	page_t*	bitmap_page;
 	ulint	space;
@@ -911,33 +911,70 @@ ibuf_reset_free_bits(
 }
 
 /**************************************************************************
-Updates the free bits for a page to reflect the present state. Does this
-in the mtr given, which means that the latching order rules virtually prevent
-any further operations for this OS thread until mtr is committed. */
+Updates the free bits for an uncompressed page to reflect the present state.
+Does this in the mtr given, which means that the latching order rules virtually
+prevent any further operations for this OS thread until mtr is committed. */
 
 void
 ibuf_update_free_bits_low(
 /*======================*/
-	ulint		zip_size,	/* in: compressed page size in bytes;
-					0 for uncompressed pages */
-	buf_block_t*	block,		/* in: index page */
-	ulint		max_ins_size,	/* in: value of maximum insert size
-					with reorganize before the latest
-					operation performed to the page */
-	mtr_t*		mtr)		/* in: mtr */
+	const buf_block_t*	block,		/* in: index page */
+	ulint			max_ins_size,	/* in: value of
+						maximum insert size
+						with reorganize before
+						the latest operation
+						performed to the page */
+	mtr_t*			mtr)		/* in/out: mtr */
 {
 	ulint	before;
 	ulint	after;
 
-	before = ibuf_index_page_calc_free_bits(zip_size, max_ins_size);
+	ut_a(!buf_block_get_page_zip(block));
+
+	before = ibuf_index_page_calc_free_bits(0, max_ins_size);
 
-	after = ibuf_index_page_calc_free(zip_size, block);
+	after = ibuf_index_page_calc_free(0, block);
 
+	/* This approach cannot be used on compressed pages, since the
+	computed value of "before" often does not match the current
+	state of the bitmap.  This is because the free space may
+	increase or decrease when a compressed page is reorganized. */
 	if (before != after) {
-		ibuf_set_free_bits_low(zip_size, block, after, mtr);
+		ibuf_set_free_bits_low(0, block, after, mtr);
 	}
 }
 
+/**************************************************************************
+Updates the free bits for a compressed page to reflect the present state.
+Does this in the mtr given, which means that the latching order rules virtually
+prevent any further operations for this OS thread until mtr is committed. */
+
+void
+ibuf_update_free_bits_zip(
+/*======================*/
+	const buf_block_t*	block,	/* in: index page */
+	mtr_t*			mtr)	/* in/out: mtr */
+{
+	page_t*	bitmap_page;
+	ulint	space;
+	ulint	page_no;
+	ulint	zip_size;
+	ulint	after;
+
+	space = buf_block_get_space(block);
+	page_no = buf_block_get_page_no(block);
+	zip_size = buf_block_get_zip_size(block);
+
+	ut_a(page_is_leaf(buf_block_get_frame(block)));
+	ut_a(zip_size);
+
+	bitmap_page = ibuf_bitmap_get_map_page(space, page_no, zip_size, mtr);
+
+	after = ibuf_index_page_calc_free_zip(zip_size, block);
+	ibuf_bitmap_page_set_bits(bitmap_page, page_no, zip_size,
+				  IBUF_BITMAP_FREE, after, mtr);
+}
+
 /**************************************************************************
 Updates the free bits for the two pages to reflect the present state. Does
 this in the mtr given, which means that the latching order rules virtually

include/ibuf0ibuf.h

@@ -67,10 +67,11 @@ ibuf_reset_free_bits(
 				if the index is a non-clustered
 				non-unique, and page level is 0 */
 /****************************************************************************
-Updates the free bits of the page in the ibuf bitmap if there is not enough
-free on the page any more. This is done in a separate mini-transaction, hence
-this operation does not restrict further work to only ibuf bitmap operations,
-which would result if the latch to the bitmap page were kept. */
+Updates the free bits of an uncompressed page in the ibuf bitmap if
+there is not enough free on the page any more. This is done in a
+separate mini-transaction, hence this operation does not restrict
+further work to only ibuf bitmap operations, which would result if the
+latch to the bitmap page were kept. */
 UNIV_INLINE
 void
 ibuf_update_free_bits_if_full(
@@ -87,20 +88,30 @@ ibuf_update_free_bits_if_full(
 				used in the latest operation, if known, or
 				ULINT_UNDEFINED */
 /**************************************************************************
-Updates the free bits for the page to reflect the present state. Does this
-in the mtr given, which means that the latching order rules virtually
+Updates the free bits for an uncompressed page to reflect the present state.
+Does this in the mtr given, which means that the latching order rules virtually
 prevent any further operations for this OS thread until mtr is committed. */
 
 void
 ibuf_update_free_bits_low(
 /*======================*/
-	ulint		zip_size,	/* in: compressed page size in bytes;
-					0 for uncompressed pages */
-	buf_block_t*	block,		/* in: index page */
-	ulint		max_ins_size,	/* in: value of maximum insert size
-					with reorganize before the latest
-					operation performed to the page */
-	mtr_t*		mtr);		/* in: mtr */
+	const buf_block_t*	block,		/* in: index page */
+	ulint			max_ins_size,	/* in: value of
+						maximum insert size
+						with reorganize before
+						the latest operation
+						performed to the page */
+	mtr_t*			mtr);		/* in/out: mtr */
+/**************************************************************************
+Updates the free bits for a compressed page to reflect the present state.
+Does this in the mtr given, which means that the latching order rules virtually
+prevent any further operations for this OS thread until mtr is committed. */
+
+void
+ibuf_update_free_bits_zip(
+/*======================*/
+	const buf_block_t*	block,	/* in: index page */
+	mtr_t*			mtr);	/* in/out: mtr */
 /**************************************************************************
 Updates the free bits for the two pages to reflect the present state. Does
 this in the mtr given, which means that the latching order rules virtually

include/ibuf0ibuf.ic

@@ -192,6 +192,40 @@ ibuf_index_page_calc_free_from_bits(
 	return(bits * (UNIV_PAGE_SIZE / IBUF_PAGE_SIZE_PER_FREE_SPACE));
 }
 
+/*************************************************************************
+Translates the free space on a compressed page to a value in the ibuf bitmap.*/
+UNIV_INLINE
+ulint
+ibuf_index_page_calc_free_zip(
+/*==========================*/
+					/* out: value for ibuf bitmap bits */
+	ulint			zip_size,
+					/* in: compressed page size in bytes */
+	const buf_block_t*	block)	/* in: buffer block */
+{
+	ulint			max_ins_size;
+	const page_zip_des_t*	page_zip;
+	lint			zip_max_ins;
+
+	ut_ad(zip_size == buf_block_get_zip_size(block));
+	ut_ad(zip_size);
+
+	max_ins_size = page_get_max_insert_size_after_reorganize(
+		buf_block_get_frame(block), 1);
+
+	page_zip = buf_block_get_page_zip(block);
+	zip_max_ins = page_zip_max_ins_size(page_zip,
+					    FALSE/* not clustered */);
+
+	if (UNIV_UNLIKELY(zip_max_ins < 0)) {
+		return(0);
+	} else if (UNIV_LIKELY(max_ins_size > (ulint) zip_max_ins)) {
+		max_ins_size = (ulint) zip_max_ins;
+	}
+
+	return(ibuf_index_page_calc_free_bits(zip_size, max_ins_size));
+}
+
 /*************************************************************************
 Translates the free space on a page to a value in the ibuf bitmap.*/
 UNIV_INLINE
@@ -203,38 +237,26 @@ ibuf_index_page_calc_free(
 					0 for uncompressed pages */
 	const buf_block_t*	block)	/* in: buffer block */
 {
-	ulint	max_ins_size;
-
 	ut_ad(zip_size == buf_block_get_zip_size(block));
 
-	max_ins_size = page_get_max_insert_size_after_reorganize(
-		buf_block_get_frame(block), 1);
-
 	if (!zip_size) {
-		return(ibuf_index_page_calc_free_bits(0, max_ins_size));
-	} else {
-		const page_zip_des_t*	page_zip;
-		lint			zip_max_ins;
+		ulint	max_ins_size;
 
-		page_zip = buf_block_get_page_zip(block);
-		zip_max_ins = page_zip_max_ins_size(page_zip,
-						    FALSE/* not clustered */);
-
-		if (UNIV_UNLIKELY(zip_max_ins < 0)) {
-			max_ins_size = 0;
-		} else if (UNIV_LIKELY(max_ins_size > (ulint) zip_max_ins)) {
-			max_ins_size = (ulint) zip_max_ins;
-		}
+		max_ins_size = page_get_max_insert_size_after_reorganize(
+			buf_block_get_frame(block), 1);
 
-		return(ibuf_index_page_calc_free_bits(zip_size, max_ins_size));
+		return(ibuf_index_page_calc_free_bits(0, max_ins_size));
+	} else {
+		return(ibuf_index_page_calc_free_zip(zip_size, block));
 	}
 }
 
 /****************************************************************************
-Updates the free bits of the page in the ibuf bitmap if there is not enough
-free on the page any more. This is done in a separate mini-transaction, hence
-this operation does not restrict further work to only ibuf bitmap operations,
-which would result if the latch to the bitmap page were kept. */
+Updates the free bits of an uncompressed page in the ibuf bitmap if
+there is not enough free on the page any more. This is done in a
+separate mini-transaction, hence this operation does not restrict
+further work to only ibuf bitmap operations, which would result if the
+latch to the bitmap page were kept. */
 UNIV_INLINE
 void
 ibuf_update_free_bits_if_full(
@@ -254,6 +276,8 @@ ibuf_update_free_bits_if_full(
 	ulint	before;
 	ulint	after;
 
+	ut_ad(!buf_block_get_page_zip(block));
+
 	before = ibuf_index_page_calc_free_bits(0, max_ins_size);
 
 	if (max_ins_size >= increase) {