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diff --git a/innobase/include/buf0lru.h b/innobase/include/buf0lru.h
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+++ b/innobase/include/buf0lru.h
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+/******************************************************
+The database buffer pool LRU replacement algorithm
+
+(c) 1995 Innobase Oy
+
+Created 11/5/1995 Heikki Tuuri
+*******************************************************/
+
+#ifndef buf0lru_h
+#define buf0lru_h
+
+#include "univ.i"
+#include "ut0byte.h"
+#include "buf0types.h"
+
+/**********************************************************************
+Tries to remove LRU flushed blocks from the end of the LRU list and put them
+to the free list. This is beneficial for the efficiency of the insert buffer
+operation, as flushed pages from non-unique non-clustered indexes are here
+taken out of the buffer pool, and their inserts redirected to the insert
+buffer. Otherwise, the flushed blocks could get modified again before read
+operations need new buffer blocks, and the i/o work done in flushing would be
+wasted. */
+
+void
+buf_LRU_try_free_flushed_blocks(void);
+/*==================================*/
+
+/*#######################################################################
+These are low-level functions
+#########################################################################*/
+
+/* Minimum LRU list length for which the LRU_old pointer is defined */
+
+#define BUF_LRU_OLD_MIN_LEN	80
+
+#define BUF_LRU_FREE_SEARCH_LEN		(5 + 2 * BUF_READ_AHEAD_AREA)
+
+/**********************************************************************
+Gets the minimum LRU_position field for the blocks in an initial segment
+(determined by BUF_LRU_INITIAL_RATIO) of the LRU list. The limit is not
+guaranteed to be precise, because the ulint_clock may wrap around. */
+
+ulint
+buf_LRU_get_recent_limit(void);
+/*==========================*/
+			/* out: the limit; zero if could not determine it */
+/**********************************************************************
+Returns a free block from the buf_pool. The block is taken off the
+free list. If it is empty, blocks are moved from the end of the
+LRU list to the free list. */
+
+buf_block_t*
+buf_LRU_get_free_block(void);
+/*=========================*/
+				/* out: the free control block */
+/**********************************************************************
+Puts a block back to the free list. */
+
+void
+buf_LRU_block_free_non_file_page(
+/*=============================*/
+	buf_block_t*	block);	/* in: block, must not contain a file page */
+/**********************************************************************
+Adds a block to the LRU list. */
+
+void
+buf_LRU_add_block(
+/*==============*/
+	buf_block_t*	block,	/* in: control block */
+	ibool		old);	/* in: TRUE if should be put to the old
+				blocks in the LRU list, else put to the
+				start; if the LRU list is very short, added to
+				the start regardless of this parameter */
+/**********************************************************************
+Moves a block to the start of the LRU list. */
+
+void
+buf_LRU_make_block_young(
+/*=====================*/
+	buf_block_t*	block);	/* in: control block */
+/**********************************************************************
+Moves a block to the end of the LRU list. */
+
+void
+buf_LRU_make_block_old(
+/*===================*/
+	buf_block_t*	block);	/* in: control block */
+/**********************************************************************
+Look for a replaceable block from the end of the LRU list and put it to
+the free list if found. */
+
+ibool
+buf_LRU_search_and_free_block(
+/*==========================*/
+				/* out: TRUE if freed */
+	ulint	n_iterations);	/* in: how many times this has been called
+				repeatedly without result: a high value
+				means that we should search farther */
+/**************************************************************************
+Validates the LRU list. */
+
+ibool
+buf_LRU_validate(void);
+/*==================*/
+/**************************************************************************
+Prints the LRU list. */
+
+void
+buf_LRU_print(void);
+/*===============*/
+
+#ifndef UNIV_NONINL
+#include "buf0lru.ic"
+#endif
+
+#endif