Adding upstream version 1:10.5.12.upstream/1%10.5.12upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 119 insertions, 0 deletions

diff --git a/storage/innobase/include/buf0rea.h b/storage/innobase/include/buf0rea.h
new file mode 100644
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+++ b/storage/innobase/include/buf0rea.h
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+/*****************************************************************************
+
+Copyright (c) 1995, 2015, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 2015, 2020, MariaDB Corporation.
+
+This program is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free Software
+Foundation; version 2 of the License.
+
+This program is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with
+this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA
+
+*****************************************************************************/
+
+/**************************************************//**
+@file include/buf0rea.h
+The database buffer read
+
+Created 11/5/1995 Heikki Tuuri
+*******************************************************/
+
+#ifndef buf0rea_h
+#define buf0rea_h
+
+#include "buf0buf.h"
+
+/** High-level function which reads a page asynchronously from a file to the
+buffer buf_pool if it is not already there. Sets the io_fix flag and sets
+an exclusive lock on the buffer frame. The flag is cleared and the x-lock
+released by the i/o-handler thread.
+@param[in]	page_id		page id
+@param[in]	zip_size	ROW_FORMAT=COMPRESSED page size, or 0
+@retval DB_SUCCESS if the page was read and is not corrupted,
+@retval DB_PAGE_CORRUPTED if page based on checksum check is corrupted,
+@retval DB_DECRYPTION_FAILED if page post encryption checksum matches but
+after decryption normal page checksum does not match.
+@retval DB_TABLESPACE_DELETED if tablespace .ibd file is missing */
+dberr_t buf_read_page(const page_id_t page_id, ulint zip_size);
+
+/** High-level function which reads a page asynchronously from a file to the
+buffer buf_pool if it is not already there. Sets the io_fix flag and sets
+an exclusive lock on the buffer frame. The flag is cleared and the x-lock
+released by the i/o-handler thread.
+@param[in,out]	space		tablespace
+@param[in]	page_id		page id
+@param[in]	zip_size	ROW_FORMAT=COMPRESSED page size, or 0
+@param[in]	sync		true if synchronous aio is desired */
+void buf_read_page_background(fil_space_t *space, const page_id_t page_id,
+			      ulint zip_size, bool sync)
+  MY_ATTRIBUTE((nonnull));
+
+/** Applies a random read-ahead in buf_pool if there are at least a threshold
+value of accessed pages from the random read-ahead area. Does not read any
+page, not even the one at the position (space, offset), if the read-ahead
+mechanism is not activated. NOTE 1: the calling thread may own latches on
+pages: to avoid deadlocks this function must be written such that it cannot
+end up waiting for these latches! NOTE 2: the calling thread must want
+access to the page given: this rule is set to prevent unintended read-aheads
+performed by ibuf routines, a situation which could result in a deadlock if
+the OS does not support asynchronous i/o.
+@param[in]	page_id		page id of a page which the current thread
+wants to access
+@param[in]	zip_size	ROW_FORMAT=COMPRESSED page size, or 0
+@param[in]	ibuf		whether we are inside ibuf routine
+@return number of page read requests issued; NOTE that if we read ibuf
+pages, it may happen that the page at the given page number does not
+get read even if we return a positive value! */
+ulint
+buf_read_ahead_random(const page_id_t page_id, ulint zip_size, bool ibuf);
+
+/** Applies linear read-ahead if in the buf_pool the page is a border page of
+a linear read-ahead area and all the pages in the area have been accessed.
+Does not read any page if the read-ahead mechanism is not activated. Note
+that the algorithm looks at the 'natural' adjacent successor and
+predecessor of the page, which on the leaf level of a B-tree are the next
+and previous page in the chain of leaves. To know these, the page specified
+in (space, offset) must already be present in the buf_pool. Thus, the
+natural way to use this function is to call it when a page in the buf_pool
+is accessed the first time, calling this function just after it has been
+bufferfixed.
+NOTE 1: as this function looks at the natural predecessor and successor
+fields on the page, what happens, if these are not initialized to any
+sensible value? No problem, before applying read-ahead we check that the
+area to read is within the span of the space, if not, read-ahead is not
+applied. An uninitialized value may result in a useless read operation, but
+only very improbably.
+NOTE 2: the calling thread may own latches on pages: to avoid deadlocks this
+function must be written such that it cannot end up waiting for these
+latches!
+NOTE 3: the calling thread must want access to the page given: this rule is
+set to prevent unintended read-aheads performed by ibuf routines, a situation
+which could result in a deadlock if the OS does not support asynchronous io.
+@param[in]	page_id		page id; see NOTE 3 above
+@param[in]	zip_size	ROW_FORMAT=COMPRESSED page size, or 0
+@param[in]	ibuf		whether if we are inside ibuf routine
+@return number of page read requests issued */
+ulint
+buf_read_ahead_linear(const page_id_t page_id, ulint zip_size, bool ibuf);
+
+/** Issues read requests for pages which recovery wants to read in.
+@param[in]	space_id	tablespace id
+@param[in]	page_nos	array of page numbers to read, with the
+highest page number the last in the array
+@param[in]	n		number of page numbers in the array */
+void buf_read_recv_pages(ulint space_id, const uint32_t* page_nos, ulint n);
+
+/** @name Modes used in read-ahead @{ */
+/** read only pages belonging to the insert buffer tree */
+#define BUF_READ_IBUF_PAGES_ONLY	131
+/** read any page */
+#define BUF_READ_ANY_PAGE		132
+/* @} */
+
+#endif