mariadb/storage/innobase/include/mtr0mtr.h
Marko Mäkelä 86767bcc0f MDEV-29593 Purge misses a chance to free not-yet-reused undo pages
trx_purge_truncate_rseg_history(): If all other conditions for
invoking trx_purge_remove_log_hdr() hold, but the state is
TRX_UNDO_CACHED instead of TRX_UNDO_TO_PURGE, detach and free it.

Tested by: Matthias Leich
2023-04-21 17:58:09 +03:00

767 lines
28 KiB
C++

/*****************************************************************************
Copyright (c) 1995, 2017, Oracle and/or its affiliates. All Rights Reserved.
Copyright (c) 2013, 2023, 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/mtr0mtr.h
Mini-transaction buffer
Created 11/26/1995 Heikki Tuuri
*******************************************************/
#pragma once
#include "fil0fil.h"
#include "dyn0buf.h"
#include "buf0buf.h"
#include "small_vector.h"
/** Start a mini-transaction. */
#define mtr_start(m) (m)->start()
/** Commit a mini-transaction. */
#define mtr_commit(m) (m)->commit()
/** Change the logging mode of a mini-transaction.
@return old mode */
#define mtr_set_log_mode(m, d) (m)->set_log_mode((d))
#ifdef UNIV_PFS_RWLOCK
# define mtr_s_lock_index(i,m) (m)->s_lock(__FILE__, __LINE__, &(i)->lock)
# define mtr_x_lock_index(i,m) (m)->x_lock(__FILE__, __LINE__, &(i)->lock)
# define mtr_sx_lock_index(i,m) (m)->u_lock(__FILE__, __LINE__, &(i)->lock)
#else
# define mtr_s_lock_index(i,m) (m)->s_lock(&(i)->lock)
# define mtr_x_lock_index(i,m) (m)->x_lock(&(i)->lock)
# define mtr_sx_lock_index(i,m) (m)->u_lock(&(i)->lock)
#endif
/** Mini-transaction memo stack slot. */
struct mtr_memo_slot_t
{
/** pointer to the object */
void *object;
/** type of the stored object */
mtr_memo_type_t type;
/** Release the object */
void release() const;
};
/** Mini-transaction handle and buffer */
struct mtr_t {
mtr_t();
~mtr_t();
/** Start a mini-transaction. */
void start();
/** Commit the mini-transaction. */
void commit();
/** Release latches of unmodified buffer pages.
@param begin first slot to release
@param end last slot to release, or get_savepoint() */
void rollback_to_savepoint(ulint begin, ulint end);
/** Release latches of unmodified buffer pages.
@param begin first slot to release */
void rollback_to_savepoint(ulint begin)
{ rollback_to_savepoint(begin, m_memo.size()); }
/** Release the last acquired buffer page latch. */
void release_last_page()
{ auto s= m_memo.size(); rollback_to_savepoint(s - 1, s); }
/** Commit a mini-transaction that is shrinking a tablespace.
@param space tablespace that is being shrunk */
ATTRIBUTE_COLD void commit_shrink(fil_space_t &space);
/** Commit a mini-transaction that is deleting or renaming a file.
@param space tablespace that is being renamed or deleted
@param name new file name (nullptr=the file will be deleted)
@param detached_handle if detached_handle != nullptr and if space is detached
during the function execution the file handle if its
node will be set to OS_FILE_CLOSED, and the previous
value of the file handle will be assigned to the
address, pointed by detached_handle.
@return whether the operation succeeded */
ATTRIBUTE_COLD bool commit_file(fil_space_t &space, const char *name,
pfs_os_file_t *detached_handle= nullptr);
/** Commit a mini-transaction that did not modify any pages,
but generated some redo log on a higher level, such as
FILE_MODIFY records and an optional FILE_CHECKPOINT marker.
The caller must hold log_sys.mutex.
This is to be used at log_checkpoint().
@param checkpoint_lsn the log sequence number of a checkpoint, or 0 */
void commit_files(lsn_t checkpoint_lsn= 0);
/** @return mini-transaction savepoint (current size of m_memo) */
ulint get_savepoint() const
{
ut_ad(is_active());
return m_memo.size();
}
/** Get the block at a savepoint */
buf_block_t *at_savepoint(ulint savepoint) const
{
ut_ad(is_active());
const mtr_memo_slot_t &slot= m_memo[savepoint];
ut_ad(slot.type < MTR_MEMO_S_LOCK);
ut_ad(slot.object);
return static_cast<buf_block_t*>(slot.object);
}
/** Try to get a block at a savepoint.
@param savepoint the savepoint right before the block was acquired
@return the block at the savepoint
@retval nullptr if no buffer block was registered at that savepoint */
buf_block_t *block_at_savepoint(ulint savepoint) const
{
ut_ad(is_active());
const mtr_memo_slot_t &slot= m_memo[savepoint];
return slot.type < MTR_MEMO_S_LOCK
? static_cast<buf_block_t*>(slot.object)
: nullptr;
}
/** Retrieve a page that has already been latched.
@param id page identifier
@param type page latch type
@return block
@retval nullptr if the block had not been latched yet */
buf_block_t *get_already_latched(const page_id_t id, mtr_memo_type_t type)
const;
/** @return the logging mode */
mtr_log_t get_log_mode() const
{
static_assert(MTR_LOG_ALL == 0, "efficiency");
return static_cast<mtr_log_t>(m_log_mode);
}
/** @return whether log is to be written for changes */
bool is_logged() const
{
static_assert(MTR_LOG_ALL == 0, "efficiency");
static_assert(MTR_LOG_NONE & MTR_LOG_NO_REDO, "efficiency");
static_assert(!(MTR_LOG_NONE & MTR_LOG_SUB), "efficiency");
return !(m_log_mode & MTR_LOG_NONE);
}
/** Change the logging mode.
@param mode logging mode
@return old mode */
mtr_log_t set_log_mode(mtr_log_t mode)
{
const mtr_log_t old_mode= get_log_mode();
m_log_mode= mode & 3;
return old_mode;
}
/** Set the log mode of a sub-minitransaction
@param mtr parent mini-transaction */
void set_log_mode_sub(const mtr_t &mtr)
{
ut_ad(mtr.m_log_mode == MTR_LOG_ALL || mtr.m_log_mode == MTR_LOG_NO_REDO);
m_log_mode= mtr.m_log_mode | MTR_LOG_SUB;
static_assert((MTR_LOG_SUB | MTR_LOG_NO_REDO) == MTR_LOG_NO_REDO, "");
}
/** Check if we are holding a block latch in exclusive mode
@param block buffer pool block to search for */
bool have_x_latch(const buf_block_t &block) const;
/** Check if we are holding a block latch in S or U mode
@param block buffer pool block to search for */
bool have_u_or_x_latch(const buf_block_t &block) const;
/** Copy the tablespaces associated with the mini-transaction
(needed for generating FILE_MODIFY records)
@param[in] mtr mini-transaction that may modify
the same set of tablespaces as this one */
void set_spaces(const mtr_t& mtr)
{
ut_ad(!m_user_space_id);
ut_ad(!m_user_space);
ut_d(m_user_space_id = mtr.m_user_space_id);
m_user_space = mtr.m_user_space;
}
/** Set the tablespace associated with the mini-transaction
(needed for generating a FILE_MODIFY record)
@param[in] space_id user or system tablespace ID
@return the tablespace */
fil_space_t* set_named_space_id(ulint space_id)
{
ut_ad(!m_user_space_id);
ut_d(m_user_space_id = static_cast<uint32_t>(space_id));
if (!space_id) {
return fil_system.sys_space;
} else {
ut_ad(m_user_space_id == space_id);
ut_ad(!m_user_space);
m_user_space = fil_space_get(space_id);
ut_ad(m_user_space);
return m_user_space;
}
}
/** Set the tablespace associated with the mini-transaction
(needed for generating a FILE_MODIFY record)
@param[in] space user or system tablespace */
void set_named_space(fil_space_t* space)
{
ut_ad(!m_user_space_id);
ut_d(m_user_space_id = static_cast<uint32_t>(space->id));
if (space->id) {
m_user_space = space;
}
}
#ifdef UNIV_DEBUG
/** Check the tablespace associated with the mini-transaction
(needed for generating a FILE_MODIFY record)
@param[in] space tablespace
@return whether the mini-transaction is associated with the space */
bool is_named_space(ulint space) const;
/** Check the tablespace associated with the mini-transaction
(needed for generating a FILE_MODIFY record)
@param[in] space tablespace
@return whether the mini-transaction is associated with the space */
bool is_named_space(const fil_space_t* space) const;
#endif /* UNIV_DEBUG */
/** Acquire a tablespace X-latch.
@param[in] space_id tablespace ID
@return the tablespace object (never NULL) */
fil_space_t* x_lock_space(ulint space_id);
/** Acquire a shared rw-latch. */
void s_lock(
#ifdef UNIV_PFS_RWLOCK
const char *file, unsigned line,
#endif
index_lock *lock)
{
lock->s_lock(SRW_LOCK_ARGS(file, line));
memo_push(lock, MTR_MEMO_S_LOCK);
}
/** Acquire an exclusive rw-latch. */
void x_lock(
#ifdef UNIV_PFS_RWLOCK
const char *file, unsigned line,
#endif
index_lock *lock)
{
lock->x_lock(SRW_LOCK_ARGS(file, line));
memo_push(lock, MTR_MEMO_X_LOCK);
}
/** Acquire an update latch. */
void u_lock(
#ifdef UNIV_PFS_RWLOCK
const char *file, unsigned line,
#endif
index_lock *lock)
{
lock->u_lock(SRW_LOCK_ARGS(file, line));
memo_push(lock, MTR_MEMO_SX_LOCK);
}
/** Acquire an exclusive tablespace latch.
@param space tablespace */
void x_lock_space(fil_space_t *space);
/** Release an index latch. */
void release(const index_lock &lock) { release(&lock); }
/** Release a latch to an unmodified page. */
void release(const buf_block_t &block) { release(&block); }
private:
/** Release an unmodified object. */
void release(const void *object);
public:
/** Mark the given latched page as modified.
@param block page that will be modified */
void set_modified(const buf_block_t &block);
/** Set the state to not-modified. This will not log the changes.
This is only used during redo log apply, to avoid logging the changes. */
void discard_modifications() { m_modifications= false; }
/** Get the LSN of commit().
@return the commit LSN
@retval 0 if the transaction only modified temporary tablespaces */
lsn_t commit_lsn() const { ut_ad(has_committed()); return m_commit_lsn; }
/** Note that we are inside the change buffer code. */
void enter_ibuf() { m_inside_ibuf= true; }
/** Note that we have exited from the change buffer code. */
void exit_ibuf() { m_inside_ibuf= false; }
/** @return true if we are inside the change buffer code */
bool is_inside_ibuf() const { return m_inside_ibuf; }
/** Note that pages has been trimed */
void set_trim_pages() { m_trim_pages= true; }
/** @return true if pages has been trimed */
bool is_trim_pages() { return m_trim_pages; }
/** Latch a buffer pool block.
@param block block to be latched
@param rw_latch RW_S_LATCH, RW_SX_LATCH, RW_X_LATCH, RW_NO_LATCH */
void page_lock(buf_block_t *block, ulint rw_latch);
/** Acquire a latch on a buffer-fixed buffer pool block.
@param savepoint savepoint location of the buffer-fixed block
@param rw_latch latch to acquire */
void upgrade_buffer_fix(ulint savepoint, rw_lock_type_t rw_latch);
/** Register a change to the page latch state. */
void lock_register(ulint savepoint, mtr_memo_type_t type)
{
mtr_memo_slot_t &slot= m_memo[savepoint];
ut_ad(slot.type <= MTR_MEMO_BUF_FIX);
ut_ad(type < MTR_MEMO_S_LOCK);
slot.type= type;
}
/** Upgrade U locks on a block to X */
void page_lock_upgrade(const buf_block_t &block);
/** Upgrade index U lock to X */
ATTRIBUTE_COLD void index_lock_upgrade();
/** Check if we are holding tablespace latch
@param space tablespace to search for
@return whether space.latch is being held */
bool memo_contains(const fil_space_t& space) const
MY_ATTRIBUTE((warn_unused_result));
#ifdef UNIV_DEBUG
/** Check if we are holding an rw-latch in this mini-transaction
@param lock latch to search for
@param type held latch type
@return whether (lock,type) is contained */
bool memo_contains(const index_lock &lock, mtr_memo_type_t type) const
MY_ATTRIBUTE((warn_unused_result));
/** Check if memo contains an index or buffer block latch.
@param object object to search
@param flags specify types of object latches
@return true if contains */
bool memo_contains_flagged(const void *object, ulint flags) const
MY_ATTRIBUTE((warn_unused_result, nonnull));
/** Check if memo contains the given page.
@param ptr pointer to within page frame
@param flags types latch to look for
@return the block
@retval nullptr if not found */
buf_block_t *memo_contains_page_flagged(const byte *ptr, ulint flags) const;
/** @return whether this mini-transaction modifies persistent data */
bool has_modifications() const { return m_modifications; }
#endif /* UNIV_DEBUG */
/** Push a buffer page to an the memo.
@param block buffer block
@param type object type: MTR_MEMO_S_LOCK, ... */
void memo_push(buf_block_t *block, mtr_memo_type_t type)
__attribute__((nonnull))
{
ut_ad(is_active());
ut_ad(type <= MTR_MEMO_PAGE_SX_MODIFY);
ut_ad(block->page.buf_fix_count());
ut_ad(block->page.in_file());
#ifdef UNIV_DEBUG
switch (type) {
case MTR_MEMO_PAGE_S_FIX:
ut_ad(block->page.lock.have_s());
break;
case MTR_MEMO_PAGE_X_FIX: case MTR_MEMO_PAGE_X_MODIFY:
ut_ad(block->page.lock.have_x());
break;
case MTR_MEMO_PAGE_SX_FIX: case MTR_MEMO_PAGE_SX_MODIFY:
ut_ad(block->page.lock.have_u_or_x());
break;
case MTR_MEMO_BUF_FIX:
break;
case MTR_MEMO_MODIFY:
case MTR_MEMO_S_LOCK: case MTR_MEMO_X_LOCK: case MTR_MEMO_SX_LOCK:
case MTR_MEMO_SPACE_X_LOCK:
ut_ad("invalid type" == 0);
}
#endif
if (!(type & MTR_MEMO_MODIFY));
else if (block->page.id().space() >= SRV_TMP_SPACE_ID)
{
block->page.set_temp_modified();
type= mtr_memo_type_t(type & ~MTR_MEMO_MODIFY);
}
else
{
m_modifications= true;
if (!m_made_dirty)
/* If we are going to modify a previously clean persistent page,
we must set m_made_dirty, so that commit() will acquire
log_sys.flush_order_mutex and insert the block into
buf_pool.flush_list. */
m_made_dirty= block->page.oldest_modification() <= 1;
}
m_memo.emplace_back(mtr_memo_slot_t{block, type});
}
/** Push an index lock or tablespace latch to the memo.
@param object index lock or tablespace latch
@param type object type: MTR_MEMO_S_LOCK, ... */
void memo_push(void *object, mtr_memo_type_t type) __attribute__((nonnull))
{
ut_ad(is_active());
ut_ad(type >= MTR_MEMO_S_LOCK);
m_memo.emplace_back(mtr_memo_slot_t{object, type});
}
/** @return the size of the log is empty */
size_t get_log_size() const { return m_log.size(); }
/** @return whether the log and memo are empty */
bool is_empty() const { return !get_savepoint() && !get_log_size(); }
/** Write an OPT_PAGE_CHECKSUM record. */
inline void page_checksum(const buf_page_t &bpage);
/** Write request types */
enum write_type
{
/** the page is guaranteed to always change */
NORMAL= 0,
/** optional: the page contents might not change */
MAYBE_NOP,
/** force a write, even if the page contents is not changing */
FORCED
};
/** Write 1, 2, 4, or 8 bytes to a file page.
@param[in] block file page
@param[in,out] ptr pointer in file page
@param[in] val value to write
@tparam l number of bytes to write
@tparam w write request type
@tparam V type of val
@return whether any log was written */
template<unsigned l,write_type w= NORMAL,typename V>
inline bool write(const buf_block_t &block, void *ptr, V val)
MY_ATTRIBUTE((nonnull));
/** Log a write of a byte string to a page.
@param[in] b buffer page
@param[in] ofs byte offset from b->frame
@param[in] len length of the data to write */
inline void memcpy(const buf_block_t &b, ulint ofs, ulint len);
/** Write a byte string to a page.
@param[in,out] b buffer page
@param[in] dest destination within b.frame
@param[in] str the data to write
@param[in] len length of the data to write
@tparam w write request type */
template<write_type w= NORMAL>
inline void memcpy(const buf_block_t &b, void *dest, const void *str,
ulint len);
/** Log a write of a byte string to a ROW_FORMAT=COMPRESSED page.
@param[in] b ROW_FORMAT=COMPRESSED index page
@param[in] offset byte offset from b.zip.data
@param[in] len length of the data to write */
inline void zmemcpy(const buf_block_t &b, ulint offset, ulint len);
/** Write a byte string to a ROW_FORMAT=COMPRESSED page.
@param[in] b ROW_FORMAT=COMPRESSED index page
@param[in] dest destination within b.zip.data
@param[in] str the data to write
@param[in] len length of the data to write
@tparam w write request type */
template<write_type w= NORMAL>
inline void zmemcpy(const buf_block_t &b, void *dest, const void *str,
ulint len);
/** Log an initialization of a string of bytes.
@param[in] b buffer page
@param[in] ofs byte offset from b->frame
@param[in] len length of the data to write
@param[in] val the data byte to write */
inline void memset(const buf_block_t &b, ulint ofs, ulint len, byte val);
/** Initialize a string of bytes.
@param[in,out] b buffer page
@param[in] ofs byte offset from b->frame
@param[in] len length of the data to write
@param[in] val the data byte to write */
inline void memset(const buf_block_t *b, ulint ofs, ulint len, byte val);
/** Log an initialization of a repeating string of bytes.
@param[in] b buffer page
@param[in] ofs byte offset from b->frame
@param[in] len length of the data to write, in bytes
@param[in] str the string to write
@param[in] size size of str, in bytes */
inline void memset(const buf_block_t &b, ulint ofs, size_t len,
const void *str, size_t size);
/** Initialize a repeating string of bytes.
@param[in,out] b buffer page
@param[in] ofs byte offset from b->frame
@param[in] len length of the data to write, in bytes
@param[in] str the string to write
@param[in] size size of str, in bytes */
inline void memset(const buf_block_t *b, ulint ofs, size_t len,
const void *str, size_t size);
/** Log that a string of bytes was copied from the same page.
@param[in] b buffer page
@param[in] d destination offset within the page
@param[in] s source offset within the page
@param[in] len length of the data to copy */
inline void memmove(const buf_block_t &b, ulint d, ulint s, ulint len);
/** Initialize an entire page.
@param[in,out] b buffer page */
void init(buf_block_t *b);
/** Free a page.
@param space tablespace
@param offset offset of the page to be freed */
void free(const fil_space_t &space, uint32_t offset);
/** Write log for partly initializing a B-tree or R-tree page.
@param block B-tree or R-tree page
@param comp false=ROW_FORMAT=REDUNDANT, true=COMPACT or DYNAMIC */
inline void page_create(const buf_block_t &block, bool comp);
/** Write log for inserting a B-tree or R-tree record in
ROW_FORMAT=REDUNDANT.
@param block B-tree or R-tree page
@param reuse false=allocate from PAGE_HEAP_TOP; true=reuse PAGE_FREE
@param prev_rec byte offset of the predecessor of the record to insert,
starting from PAGE_OLD_INFIMUM
@param info_bits info_bits of the record
@param n_fields_s number of fields << 1 | rec_get_1byte_offs_flag()
@param hdr_c number of common record header bytes with prev_rec
@param data_c number of common data bytes with prev_rec
@param hdr record header bytes to copy to the log
@param hdr_l number of copied record header bytes
@param data record payload bytes to copy to the log
@param data_l number of copied record data bytes */
inline void page_insert(const buf_block_t &block, bool reuse,
ulint prev_rec, byte info_bits,
ulint n_fields_s, size_t hdr_c, size_t data_c,
const byte *hdr, size_t hdr_l,
const byte *data, size_t data_l);
/** Write log for inserting a B-tree or R-tree record in
ROW_FORMAT=COMPACT or ROW_FORMAT=DYNAMIC.
@param block B-tree or R-tree page
@param reuse false=allocate from PAGE_HEAP_TOP; true=reuse PAGE_FREE
@param prev_rec byte offset of the predecessor of the record to insert,
starting from PAGE_NEW_INFIMUM
@param info_status rec_get_info_and_status_bits()
@param shift unless !reuse: number of bytes the PAGE_FREE is moving
@param hdr_c number of common record header bytes with prev_rec
@param data_c number of common data bytes with prev_rec
@param hdr record header bytes to copy to the log
@param hdr_l number of copied record header bytes
@param data record payload bytes to copy to the log
@param data_l number of copied record data bytes */
inline void page_insert(const buf_block_t &block, bool reuse,
ulint prev_rec, byte info_status,
ssize_t shift, size_t hdr_c, size_t data_c,
const byte *hdr, size_t hdr_l,
const byte *data, size_t data_l);
/** Write log for deleting a B-tree or R-tree record in ROW_FORMAT=REDUNDANT.
@param block B-tree or R-tree page
@param prev_rec byte offset of the predecessor of the record to delete,
starting from PAGE_OLD_INFIMUM */
inline void page_delete(const buf_block_t &block, ulint prev_rec);
/** Write log for deleting a COMPACT or DYNAMIC B-tree or R-tree record.
@param block B-tree or R-tree page
@param prev_rec byte offset of the predecessor of the record to delete,
starting from PAGE_NEW_INFIMUM
@param hdr_size record header size, excluding REC_N_NEW_EXTRA_BYTES
@param data_size data payload size, in bytes */
inline void page_delete(const buf_block_t &block, ulint prev_rec,
size_t hdr_size, size_t data_size);
/** Write log for initializing an undo log page.
@param block undo page */
inline void undo_create(const buf_block_t &block);
/** Write log for appending an undo log record.
@param block undo page
@param data record within the undo page
@param len length of the undo record, in bytes */
inline void undo_append(const buf_block_t &block,
const void *data, size_t len);
/** Trim the end of a tablespace.
@param id first page identifier that will not be in the file */
inline void trim_pages(const page_id_t id);
/** Write a log record about a file operation.
@param type file operation
@param space_id tablespace identifier
@param path file path
@param new_path new file path for type=FILE_RENAME */
inline void log_file_op(mfile_type_t type, ulint space_id,
const char *path,
const char *new_path= nullptr);
/** Add freed page numbers to freed_pages */
void add_freed_offset(fil_space_t *space, uint32_t page)
{
ut_ad(is_named_space(space));
if (!m_freed_pages)
{
m_freed_pages= new range_set();
ut_ad(!m_freed_space);
m_freed_space= space;
}
else
ut_ad(m_freed_space == space);
m_freed_pages->add_value(page);
}
/** Determine the added buffer fix count of a block.
@param block block to be checked
@return number of buffer count added by this mtr */
uint32_t get_fix_count(const buf_block_t *block) const;
/** type of page flushing is needed during commit() */
enum page_flush_ahead
{
/** no need to trigger page cleaner */
PAGE_FLUSH_NO= 0,
/** asynchronous flushing is needed */
PAGE_FLUSH_ASYNC,
/** furious flushing is needed */
PAGE_FLUSH_SYNC
};
private:
/** Log a write of a byte string to a page.
@param block buffer page
@param offset byte offset within page
@param data data to be written
@param len length of the data, in bytes */
inline void memcpy_low(const buf_block_t &block, uint16_t offset,
const void *data, size_t len);
/**
Write a log record.
@tparam type redo log record type
@param id persistent page identifier
@param bpage buffer pool page, or nullptr
@param len number of additional bytes to write
@param alloc whether to allocate the additional bytes
@param offset byte offset, or 0 if the record type does not allow one
@return end of mini-transaction log, minus len */
template<byte type>
inline byte *log_write(const page_id_t id, const buf_page_t *bpage,
size_t len= 0, bool alloc= false, size_t offset= 0);
/** Write an EXTENDED log record.
@param block buffer pool page
@param type extended record subtype; @see mrec_ext_t */
inline void log_write_extended(const buf_block_t &block, byte type);
/** Append the redo log records to the redo log buffer.
@return {start_lsn,flush_ahead} */
std::pair<lsn_t,page_flush_ahead> do_write();
/** Append the redo log records to the redo log buffer.
@param len number of bytes to write
@return {start_lsn,flush_ahead} */
inline std::pair<lsn_t,page_flush_ahead> finish_write(ulint len);
/** Release all latches. */
void release();
/** Release the resources */
inline void release_resources();
#ifdef UNIV_DEBUG
public:
/** @return whether the mini-transaction is active */
bool is_active() const
{ ut_ad(!m_commit || m_start); return m_start && !m_commit; }
/** @return whether the mini-transaction has been committed */
bool has_committed() const { ut_ad(!m_commit || m_start); return m_commit; }
/** @return whether the mini-transaction is freeing an index tree */
bool is_freeing_tree() const { return m_freeing_tree; }
/** Notify that the mini-transaction is freeing an index tree */
void freeing_tree() { m_freeing_tree= true; }
private:
/** whether start() has been called */
bool m_start= false;
/** whether commit() has been called */
bool m_commit= false;
/** whether freeing_tree() has been called */
bool m_freeing_tree= false;
#endif
/** The page of the most recent m_log record written, or NULL */
const buf_page_t* m_last;
/** The current byte offset in m_last, or 0 */
uint16_t m_last_offset;
/** specifies which operations should be logged; default MTR_LOG_ALL */
uint16_t m_log_mode:2;
/** whether at least one persistent page was written to */
uint16_t m_modifications:1;
/** whether at least one previously clean buffer pool page was written to */
uint16_t m_made_dirty:1;
/** whether change buffer is latched; only needed in non-debug builds
to suppress some read-ahead operations, @see ibuf_inside() */
uint16_t m_inside_ibuf:1;
/** whether the pages has been trimmed */
uint16_t m_trim_pages:1;
#ifdef UNIV_DEBUG
/** Persistent user tablespace associated with the
mini-transaction, or 0 (TRX_SYS_SPACE) if none yet */
uint32_t m_user_space_id;
#endif /* UNIV_DEBUG */
/** acquired dict_index_t::lock, fil_space_t::latch, buf_block_t */
small_vector<mtr_memo_slot_t, 16> m_memo;
/** mini-transaction log */
mtr_buf_t m_log;
/** user tablespace that is being modified by the mini-transaction */
fil_space_t* m_user_space;
/** LSN at commit time */
lsn_t m_commit_lsn;
/** tablespace where pages have been freed */
fil_space_t *m_freed_space= nullptr;
/** set of freed page ids */
range_set *m_freed_pages= nullptr;
};