btr_search_drop_page_hash_index(): Replace the Boolean parameter
with const dict_index_t *not_garbage. If buf_block_t::index points
to that, there is no need to acquire btr_sea::partition::latch.
The old parameter bool garbage_collect=false is equivalent to the
parameter not_garbage=nullptr. The parameter garbage_collect=true
will be replaced either with the actual index that is associated
with the buffer page, or with a bogus pointer not_garbage=-1 to
indicate that any lazily entries for a freed index need to be removed.
buf_page_get_low(), buf_page_get_gen(), mtr_t::page_lock(),
mtr_t::upgrade_buffer_fix(): Do not invoke
btr_search_drop_page_hash_index(). Our caller will have to do it
when appropriate.
buf_page_create_low(): Keep invoking btr_search_drop_page_hash_index().
This is the normal way of lazily dropping the adaptive hash index
after a DDL operation such as DROP INDEX operation.
btr_block_get(), btr_root_block_get(), btr_root_adjust_on_import(),
btr_read_autoinc_with_fallback(), btr_cur_instant_init_low(),
btr_cur_t::search_leaf(), btr_cur_t::pessimistic_search_leaf(),
btr_pcur_optimistic_latch_leaves(), dict_stats_analyze_index_below_cur():
Invoke btr_search_drop_page_hash_index(block, index) for pages that
may be leaf pages. No adaptive hash index may have been created on
anything else than a B-tree leaf page.
btr_cur_search_to_nth_level(): Do not invoke
btr_search_drop_page_hash_index(), because we are only accessing
non-leaf pages and the adaptive hash index may only have been created
on leaf pages.
btr_page_alloc_for_ibuf() and many other callers of buf_page_get_gen()
or similar functions do not invoke btr_search_drop_page_hash_index(),
because the adaptive hash index is never created on such pages.
If a page in the tablespace was freed as part of a DDL operation and
reused for something else, then buf_page_create_low() will take care
of dropping the adaptive hash index before the freed page will be
modified.
It is notable that while the flst_ functions may access pages that are
related to allocating B-tree index pages (the BTR_SEG_TOP and BTR_SEG_LEAF
linked from the index root page), those pages themselves can never be
stored in the adaptive hash index. Therefore, it is not necessary to
invoke btr_search_drop_page_hash_index() on them.
Reviewed by: Vladislav Lesin
Now that ut_fold_ulint_pair() and ut_fold_binary() are no longer needed
for anything else than compatibility with old InnoDB data files that may
use innodb_checksum_algorithm=innodb, let us move the code to a single
compilation unit.
Reviewed by: Vladislav Lesin
For the adaptive hash index, dtuple_fold() and rec_fold() were employing
a slow rolling hash algorithm, computing hash values ("fold") for one
field and one byte at a time, while depending on calls to
rec_get_offsets().
We already have optimized implementations of CRC-32C and have been
successfully using that function in some other InnoDB tables, but not
yet in the adaptive hash index.
Any linear function such as any CRC will fail the avalanche test that
any cryptographically secure hash function is expected to pass:
any single-bit change in the input key should affect on average half
the bits in the output.
But we always were happy with less than cryptographically secure:
in fact, ut_fold_ulint_pair() or ut_fold_binary() are just about as
linear as any CRC, using a combination of multiplication and addition,
partly carry-less. It is worth noting that exclusive-or corresponds to
carry-less subtraction or addition in a binary Galois field, or GF(2).
We only need some way of reducing key prefixes into hash values.
The CRC-32C should be better than a Rabin–Karp rolling hash algorithm.
Compared to the old hash algorithm, it has the drawback that there will
be only 32 bits of entropy before we choose the hash table cell by a
modulus operation. The size of each adaptive hash index array is
(innodb_buffer_pool_size / 512) / innodb_adaptive_hash_index_parts.
With the maximum number of partitions (512), we would not exceed 1<<32
elements per array until the buffer pool size exceeds 1<<50 bytes (1 PiB).
We would hit other limits before that: the virtual address space on many
contemporary 64-bit processor implementations is only 48 bits (256 TiB).
So, we can simply go for the SIMD accelerated CRC-32C.
rec_fold(): Take a combined parameter n_bytes_fields. Determine the
length of each field on the fly, and compute CRC-32C over a single
contiguous range of bytes, from the start of the record payload area
to the end of the last full or partial field. For secondary index records
in ROW_FORMAT=REDUNDANT, also the data area that is reserved for NULL
values (to facilitate in-place updates between NULL and NOT NULL values)
will be included in the count. Luckily, InnoDB always zero-initialized
such unused area; refer to data_write_sql_null() in
rec_convert_dtuple_to_rec_old(). For other than ROW_FORMAT=REDUNDANT,
no space is allocated for NULL values, and therefore the CRC-32C will
only cover the actual payload of the key prefix.
dtuple_fold(): For ROW_FORMAT=REDUNDANT, include the dummy NULL values
in the CRC-32C, so that the values will be comparable with rec_fold().
innodb_ahi-t: A unit test for rec_fold() and dtuple_fold().
btr_search_build_page_hash_index(), btr_search_drop_page_hash_index():
Use a fixed-size stack buffer for computing the fold values, to avoid
dynamic memory allocation.
btr_search_drop_page_hash_index(): Do not release part.latch if we
need to invoke multiple batches of rec_fold().
dtuple_t: Allocate fewer bits for the fields. The maximum number of
data fields is about 1023, so uint16_t will be fine for them. The
info_bits is stored in less than 1 byte.
ut_pair_min(), ut_pair_cmp(): Remove. We can actually combine and compare
int(n_fields << 16 | n_bytes).
PAGE_CUR_LE_OR_EXTENDS, PAGE_CUR_DBG: Remove. These were never defined,
because they would only work with latin1_swedish_ci if at all.
btr_cur_t::check_mismatch(): Replaces !btr_search_check_guess().
cmp_dtuple_rec_bytes(): Replaces cmp_dtuple_rec_with_match_bytes().
Determine the offsets of fields on the fly.
page_cur_try_search_shortcut_bytes(): This caller of
cmp_dtuple_rec_bytes() will not be invoked on the change buffer tree.
cmp_dtuple_rec_leaf(): Replaces cmp_dtuple_rec_with_match()
for comparing leaf-page records.
buf_block_t::ahi_left_bytes_fields: Consolidated Atomic_relaxed<uint32_t>
of curr_left_side << 31 | curr_n_bytes << 16 | curr_n_fields.
The other set of parameters (n_fields, n_bytes, left_side) was removed
as redundant.
btr_search_update_hash_node_on_insert(): Merged to
btr_search_update_hash_on_insert().
btr_search_build_page_hash_index(): Take combined left_bytes_fields
instead of n_fields, n_bytes, left_side.
btr_search_update_block_hash_info(), btr_search_update_hash_ref():
Merged to btr_search_info_update_hash().
btr_cur_t::n_bytes_fields: Replaces n_bytes << 16 | n_fields.
We also remove many redundant checks of btr_search.enabled.
If we are holding any btr_sea::partition::latch, then a nonnull pointer
in buf_block_t::index must imply that the adaptive hash index is enabled.
Reviewed by: Vladislav Lesin
Let us use implement a simple fixed-size allocator for the adaptive hash
index, insted of complicating mem_heap_t or mem_block_info_t.
MEM_HEAP_BTR_SEARCH: Remove.
mem_block_info_t::free_block(), mem_heap_free_block_free(): Remove.
mem_heap_free_top(), mem_heap_get_top(): Remove.
btr_sea::partition::spare: Replaces mem_block_info_t::free_block.
This keeps one spare block per adaptive hash index partition, to
process an insert.
We must not wait for buf_pool.mutex while holding
any btr_sea::partition::latch. That is why we cache one block for
future allocations. This is protected by a new
btr_sea::partition::blocks_mutex in order to relieve pressure on
btr_sea::partition::latch.
btr_sea::partition::prepare_insert(): Replaces
btr_search_check_free_space_in_heap().
btr_sea::partition::erase(): Replaces ha_search_and_delete_if_found().
btr_sea::partition::cleanup_after_erase(): Replaces the most part of
ha_delete_hash_node(). Unlike the previous implementation, we will
retain a spare block for prepare_insert().
This should reduce some contention on buf_pool.mutex.
btr_search.n_parts: Replaces btr_ahi_parts.
btr_search.enabled: Replaces btr_search_enabled. This must hold
whenever buf_block_t::index is set while a thread is holding a
btr_sea::partition::latch.
dict_index_t::search_info: Remove pointer indirection, and use
Atomic_relaxed or Atomic_counter for most fields.
btr_search_guess_on_hash(): Let the caller ensure that latch_mode is
BTR_MODIFY_LEAF or BTR_SEARCH_LEAF. Release btr_sea::partition::latch
before buffer-fixing the block. The page latch that we already acquired
is preventing buffer pool eviction. We must validate both
block->index and block->page.state while holding part.latch
in order to avoid race conditions with buffer page relocation
or buf_pool_t::resize().
btr_search_check_guess(): Remove the constant parameter
can_only_compare_to_cursor_rec=false.
ahi_node: Replaces ha_node_t.
This has been tested by running the regression test suite
with the adaptive hash index enabled:
./mtr --mysqld=--loose-innodb-adaptive-hash-index=ON
Reviewed by: Vladislav Lesin
- InnoDB fails to recover the full crc32 encrypted page from
doublewrite buffer. The reason is that buf_dblwr_t::recover()
fails to identify the space id from the page because the page has
been encrypted from FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION bytes.
Fix:
===
buf_dblwr_t::recover(): preserve any pages whose space_id
does not match a known tablespace. These could be encrypted pages
of tablespaces that had been created with
innodb_checksum_algorithm=full_crc32.
buf_page_t::read_complete(): If the page looks corrupted and the
tablespace is encrypted and in full_crc32 format, try to
restore the page from doublewrite buffer.
recv_dblwr_t::recover_encrypted_page(): Find the page which
has the same page number and try to decrypt the page using
space->crypt_data. After decryption, compare the space id.
Write the recovered page back to the file.
In function buf_page_create_low(), remove duplicate code that
over-write the ibuf_exist variable incorrectly when only compressed
page is loaded in buffer pool. This would help removing any old change
buffer record immediately before re-using the page.
If InnoDB is killed in such a way that there had been no writes
to a newly resized ib_logfile101 after it replaced ib_logfile0
in log_t::write_checkpoint(), it is possible that recovery will
accidentally interpret some garbage at the end of the log as valid.
log_t::write_buf(): To prevent the corruption, write an extra NUL byte
at the end of log_sys.resize_buf, like we always did for the main
log_sys.buf. To remove some conditional branches from a time critical
code path, we instantiate a separate template for the rare case that the
log is being resized. Define as __attribute__((always_inline)) so that
this will be inlined also in the rare case the log is being resized.
log_t::writer: Pointer to the current implementation of
log_t::write_buf(). For quick access, this is located in the
same cache line with log_sys.latch, which protects it.
log_t::writer_update(): Update log_sys.writer.
log_t::resize_write_buf(): Remove ATTRIBUTE_NOINLINE ATTRIBUTE_COLD.
Now that log_t::write_buf() will be instantiated separately for the
rare case of log resizing being in progress, there is no need to forbid
this code from being inlined.
Thanks to Thirunarayanan Balathandayuthapani for finding the
root cause of this bug and suggesting the fix of writing an extra
NUL byte.
Reviewed by: Debarun Banerjee
This regression is introduced in 10.6 by following commit.
commit 35d477dd1d
MDEV-34453 Trying to read 16384 bytes at 70368744161280
The page state could change after being buffer-fixed and needs to be
read again after locking the page.
Under unknown circumstances, the SQL layer may wrongly disregard an
invocation of thd_mark_transaction_to_rollback() when an InnoDB
transaction had been aborted (rolled back) due to one of the following errors:
* HA_ERR_LOCK_DEADLOCK
* HA_ERR_RECORD_CHANGED (if innodb_snapshot_isolation=ON)
* HA_ERR_LOCK_WAIT_TIMEOUT (if innodb_rollback_on_timeout=ON)
Such an error used to cause a crash of InnoDB during transaction commit.
These changes aim to catch and report the error earlier, so that not only
this crash can be avoided but also the original root cause be found and
fixed more easily later.
The idea of this fix is from Michael 'Monty' Widenius.
HA_ERR_ROLLBACK: A new error code that will be translated into
ER_ROLLBACK_ONLY, signalling that the current transaction
has been aborted and the only allowed action is ROLLBACK.
trx_t::state: Add TRX_STATE_ABORTED that is like
TRX_STATE_NOT_STARTED, but noting that the transaction had been
rolled back and aborted.
trx_t::is_started(): Replaces trx_is_started().
ha_innobase: Check the transaction state in various places.
Simplify the logic around SAVEPOINT.
ha_innobase::is_valid_trx(): Replaces ha_innobase::is_read_only().
The InnoDB logic around transaction savepoints, commit, and rollback
was unnecessarily complex and might have contributed to this
inconsistency. So, we are simplifying that logic as well.
trx_savept_t: Replace with const undo_no_t*. When we rollback to
a savepoint, all we need to know is the number of undo log records
that must survive.
trx_named_savept_t, DB_NO_SAVEPOINT: Remove. We can store undo_no_t
directly in the space allocated at innobase_hton->savepoint_offset.
fts_trx_create(): Do not copy previous savepoints.
fts_savepoint_rollback(): If a savepoint was not found, roll back
everything after the default savepoint of fts_trx_create().
The test innodb_fts.savepoint is extended to cover this code.
Reviewed by: Vladislav Lesin
Tested by: Matthias Leich
buf_dblwr_t::recover(): Correct a debug assertion failure that had
been added in commit bb47e575de (MDEV-34830).
The server may have been killed while a log write was in progress, and
therefore recv_sys.scanned_lsn may be up to RECV_PARSING_BUF_SIZE bytes
ahead of recv_sys.recovered_lsn.
Thanks to Matthias Leich for providing "rr replay" traces and
testing this.
fil_space_t::create(): Instead of invoking the default fil_space_t
constructor on a zero-filled buffer, allocate an uninitialized buffer
and invoke an explicitly defined constructor on it. Also, specify
initializer expressions for all constant data members, so that all of them
will be initialized in the constructor.
fil_space_t::being_imported: Replaces part of fil_space_t::purpose.
fil_space_t::is_being_imported(), fil_space_t::is_temporary():
Replaces fil_space_t::purpose.
fil_space_t:🆔 Changed the type from ulint to uint32_t to reduce
incompatibility with later branches that include
commit ca501ffb04 (MDEV-26195).
fil_space_t::try_to_close(): Do not attempt to close files that are
in an I/O bound phase of ALTER TABLE…IMPORT TABLESPACE.
log_file_op, first_page_init: recv_spaces_t:
Use uint32_t for the tablespace id.
Reviewed by: Debarun Banerjee
buf_block_alloc(): Define as an alias in buf0lru.h, which defines
the underlying buf_LRU_get_free_block().
buf_block_free(): Define as an alias of the non-inline function
buf_pool.free_block(block).
Reviewed by: Vladislav Lesin
A race condition was observed between two buf_page_get_zip() for a page.
One of them had proceeded to buf_read_page(), allocating and x-latching
a buf_block_t that initially comprises only an uncompressed page frame.
While that thread was waiting inside buf_block_alloc(), another thread
would try to access the same page. Without acquiring a page latch, it
would wrongly conclude that there is corruption because no compressed
page frame exists for the block.
buf_page_get_zip(): Simplify the logic and correct the documentation.
Always acquire a shared latch to prevent any race condition with a
concurrent read operation. No longer increment a buffer-fix; the latch
is sufficient for preventing page relocation or eviction.
buf_read_page(): Add the parameter bool unzip=true. In buf_page_get_zip()
there is no need to allocate an uncompressed page frame for reading a
compressed BLOB page. We only need that for other ROW_FORMAT=COMPRESSED
pages, or for writing compressed BLOB pages.
btr_copy_zblob_prefix(): Remove the message "Cannot load compressed BLOB"
because buf_page_get_zip() will already have reported a more specific
error whenever it returns nullptr.
row_merge_buf_add(): Do not crash on BLOB corruption, but return an
error instead. (In debug builds, an assertion will fail if this
corruption is noticed.)
Reviewed by: Debarun Banerjee
The HASH_ macros are unnecessarily obfuscating the logic,
so we had better replace them.
hash_cell_t::search(): Implement most of the HASH_DELETE logic,
for a subsequent insert or remove().
hash_cell_t::remove(): Remove an element.
hash_cell_t::find(): Implement the HASH_SEARCH logic.
xb_filter_hash_free(): Avoid any hash table lookup;
just traverse the hash bucket chains and free each element.
xb_register_filter_entry(): Search databases_hash only once.
rm_if_not_found(): Make use of find_filter_in_hashtable().
dict_sys_t::acquire_temporary_table(), dict_sys_t::find_table():
Define non-inline to avoid unnecessary code duplication.
dict_sys_t::add(dict_table_t *table), dict_table_rename_in_cache():
Look for duplicate while finding the insert position.
dict_table_change_id_in_cache(): Merged to the only caller
row_discard_tablespace().
hash_insert(): Helper function of dict_sys_t::resize().
fil_space_t::create(): Look for a duplicate (and crash if found)
when searching for the insert position.
lock_rec_discard(): Take the hash array cell as a parameter
to avoid a duplicated lookup.
lock_rec_free_all_from_discard_page(): Remove a parameter.
Reviewed by: Debarun Banerjee
buf_pool_t::LRU_warn(): Also clear the try_LRU_scan flag, to ensure
that need_LRU_eviction() will hold. This should ensure progress when
buf_LRU_get_free_block() is expecting buf_flush_page_cleaner() to
make some room, even when buf_pool.LRU.count is small.
This hang was observed in trx_lists_init_at_db_start() while the last
batch of crash recovery was in progress, but it could theoretically
be possible also when a large part of the buffer pool is occupied by
record locks or the adaptive hash index.
Reviewed by: Debarun Banerjee
A debug assertion in buf_LRU_get_free_block() could fail if
SET GLOBAL innodb_lru_scan_depth is being executed during a workload
that involves allocating buffer pool pages.
buf_pool_t::LRU_scan_depth: Replaces srv_LRU_scan_depth.
buf_pool_t::flush_neighbors: Replaces srv_flush_neighbors.
innodb_buf_pool_update<T>(): Update a parameter of buf_pool
while holding buf_pool.mutex.
The 'if (!m_abort) break' condition was inverted by accident.
Constrain the test case to environments where there is cgroupv2
runtime environment which is the same case that will pass a memory
pressure initialization.
Remove the explicit garbage_collection trigger as it hides the abnormal
termination error on the event loop for memory pressure. This
also means there is no support in non-cgroupv2 environments
(possibly some container environments).
As the trigger to memory pressure is via a different thread we
need to wait until a "[mM]emory pressure" log message is there to
know it has succeeded or failed.
Thanks Kristian Nielsen for noticing and review.
The invariant of write-ahead logging is that before any change to a
page is written to the data file, the corresponding log record must
must first have been durably written.
In crash recovery, there were some sloppy checks for this. Let us
implement accurate checks and flag an inconsistency as a hard error,
so that we can avoid further corruption of a corrupted database.
For data extraction from the corrupted database, innodb_force_recovery
can be used.
Before recovery is reading any data pages or invoking
buf_dblwr_t::recover() to recover torn pages from the
doublewrite buffer, InnoDB will have parsed the log until the
final LSN and updated log_sys.lsn to that. So, we can rely on
log_sys.lsn at all times. The doublewrite buffer recovery has been
refactored in such a way that the recv_sys.dblwr.pages may be consulted
while discovering files and their page sizes, but nothing will be
written back to data files before buf_dblwr_t::recover() is invoked.
recv_max_page_lsn, recv_lsn_checks_on: Remove.
recv_sys_t::validate_checkpoint(): Validate the write-ahead-logging
condition at the end of the recovery.
recv_dblwr_t::validate_page(): Keep track of the maximum LSN
(if we are checking a non-doublewrite copy of a page) but
do not complain LSN being in the future. The doublewrite buffer
is a special case, because it will be read early during recovery.
Besides, starting with commit 762bcb81b5
the dblwr=true copies of pages may legitimately be "too new".
recv_dblwr_t::find_page(): Find a valid page with the smallest
FIL_PAGE_LSN that is in the valid range for recovery.
recv_dblwr_t::restore_first_page(): Replaced by find_page().
Only buf_dblwr_t::recover() will write to data files.
buf_dblwr_t::recover(): Simplify the message output. Do attempt
doublewrite recovery on user page read error. Ignore doublewrite
pages whose FIL_PAGE_LSN is outside the usable bounds. Previously,
we could wrongly recover a too new page from the doublewrite buffer.
It is unlikely that this could have lead to an actual error.
Write back all recovered pages from the doublewrite buffer here,
including for the first page of any tablespace.
buf_page_is_corrupted(): Distinguish the return values
CORRUPTED_FUTURE_LSN and CORRUPTED_OTHER.
buf_page_check_corrupt(): Return the error code DB_CORRUPTION
in case the LSN is in the future.
Datafile::read_first_page_flags(): Split from read_first_page().
Take a copy of the first page as a parameter.
recv_sys_t::free_corrupted_page(): Take the file as a parameter
and return whether a message was displayed. This avoids some duplicated
and incomplete error messages.
buf_page_t::read_complete(): Remove some redundant output and always
display the name of the corrupted file. Never return DB_FAIL;
use it only in internal error handling.
IORequest::read_complete(): Assume that buf_page_t::read_complete()
will have reported any error.
fil_space_t::set_corrupted(): Return whether this is the first time
the tablespace had been flagged as corrupted.
Datafile::validate_first_page(), fil_node_open_file_low(),
fil_node_open_file(), fil_space_t::read_page0(),
fil_node_t::read_page0(): Add a parameter for a copy of the
first page, and a parameter to indicate whether the FIL_PAGE_LSN
check should be suppressed. Before buf_dblwr_t::recover() is
invoked, we cannot validate the FIL_PAGE_LSN, but we can trust the
FSP_SPACE_FLAGS and the tablespace ID that may be present in a
potentially too new copy of a page.
Reviewed by: Debarun Banerjee
The invariant of write-ahead logging is that before any change to a
page is written to the data file, the corresponding log record must
must first have been durably written.
On crash recovery, there were some sloppy checks for this. Let us
implement accurate checks and flag an inconsistency as a hard error,
so that we can avoid further corruption of a corrupted database.
For data extraction from the corrupted database, innodb_force_recovery
can be used.
Before recovery is reading any data pages or invoking
buf_dblwr_t::recover() to recover torn pages from the
doublewrite buffer, InnoDB will have parsed the log until the
final LSN and updated log_sys.lsn to that. So, we can rely on
log_sys.lsn at all times. The doublewrite buffer recovery has been
refactored in such a way that the recv_sys.dblwr.pages may be consulted
while discovering files and their page sizes, but nothing will be
written back to data files before buf_dblwr_t::recover() is invoked.
A section of the test mariabackup.innodb_redo_overwrite
that is parsing some mariadb-backup --backup output has
been removed, because that output "redo log block is overwritten"
would often be missing in a Microsoft Windows environment
as a result of these changes.
recv_max_page_lsn, recv_lsn_checks_on: Remove.
recv_sys_t::validate_checkpoint(): Validate the write-ahead-logging
condition at the end of the recovery.
recv_dblwr_t::validate_page(): Keep track of the maximum LSN
(if we are checking a non-doublewrite copy of a page) but
do not complain LSN being in the future. The doublewrite buffer
is a special case, because it will be read early during recovery.
Besides, starting with commit 762bcb81b5
the dblwr=true copies of pages may legitimately be "too new".
recv_dblwr_t::find_page(): Find a valid page with the smallest
FIL_PAGE_LSN that is in the valid range for recovery.
recv_dblwr_t::restore_first_page(): Replaced by find_page().
Only buf_dblwr_t::recover() will write to data files.
buf_dblwr_t::recover(): Simplify the message output. Do attempt
doublewrite recovery on user page read error. Ignore doublewrite
pages whose FIL_PAGE_LSN is outside the usable bounds. Previously,
we could wrongly recover a too new page from the doublewrite buffer.
It is unlikely that this could have lead to an actual error.
Write back all recovered pages from the doublewrite buffer here,
including for the first page of any tablespace.
buf_page_is_corrupted(): Distinguish the return values
CORRUPTED_FUTURE_LSN and CORRUPTED_OTHER.
buf_page_check_corrupt(): Return the error code DB_CORRUPTION
in case the LSN is in the future.
Datafile::read_first_page(): Handle FSP_SPACE_FLAGS=0xffffffff
in the same way on both 32-bit and 64-bit architectures.
Datafile::read_first_page_flags(): Split from read_first_page().
Take a copy of the first page as a parameter.
recv_sys_t::free_corrupted_page(): Take the file as a parameter
and return whether a message was displayed. This avoids some duplicated
and incomplete error messages.
buf_page_t::read_complete(): Remove some redundant output and always
display the name of the corrupted file. Never return DB_FAIL;
use it only in internal error handling.
IORequest::read_complete(): Assume that buf_page_t::read_complete()
will have reported any error.
fil_space_t::set_corrupted(): Return whether this is the first time
the tablespace had been flagged as corrupted.
Datafile::validate_first_page(), fil_node_open_file_low(),
fil_node_open_file(), fil_space_t::read_page0(),
fil_node_t::read_page0(): Add a parameter for a copy of the
first page, and a parameter to indicate whether the FIL_PAGE_LSN
check should be suppressed. Before buf_dblwr_t::recover() is
invoked, we cannot validate the FIL_PAGE_LSN, but we can trust the
FSP_SPACE_FLAGS and the tablespace ID that may be present in a
potentially too new copy of a page.
Reviewed by: Debarun Banerjee
In some places, there were redundant comparisons against TRX_SYS_SPACE
or SRV_TMP_SPACE_ID. The temporary tablespace is never the subject of
log-based recovery.
Also, consistently check for SRV_SPACE_ID_UPPER_BOUND.
Reviewed by: Debarun Barerjee
When using the default innodb_log_buffer_size=2m, mariadb-backup --backup
would spend a lot of time re-reading and re-parsing the log. For reads,
it would be beneficial to memory-map the entire ib_logfile0 to the
address space (typically 48 bits or 256 TiB) and read it from there,
both during --backup and --prepare.
We will introduce the Boolean read-only parameter innodb_log_file_mmap
that will be OFF by default on most platforms, to avoid aggressive
read-ahead of the entire ib_logfile0 in when only a tiny portion would be
accessed. On Linux and FreeBSD the default is innodb_log_file_mmap=ON,
because those platforms define a specific mmap(2) option for enabling
such read-ahead and therefore it can be assumed that the default would
be on-demand paging. This parameter will only have impact on the initial
InnoDB startup and recovery. Any writes to the log will use regular I/O,
except when the ib_logfile0 is stored in a specially configured file system
that is backed by persistent memory (Linux "mount -o dax").
We also experimented with allowing writes of the ib_logfile0 via a
memory mapping and decided against it. A fundamental problem would be
unnecessary read-before-write in case of a major page fault, that is,
when a new, not yet cached, virtual memory page in the circular
ib_logfile0 is being written to. There appears to be no way to tell
the operating system that we do not care about the previous contents of
the page, or that the page fault handler should just zero it out.
Many references to HAVE_PMEM have been replaced with references to
HAVE_INNODB_MMAP.
The predicate log_sys.is_pmem() has been replaced with
log_sys.is_mmap() && !log_sys.is_opened().
Memory-mapped regular files differ from MAP_SYNC (PMEM) mappings in the
way that an open file handle to ib_logfile0 will be retained. In both
code paths, log_sys.is_mmap() will hold. Holding a file handle open will
allow log_t::clear_mmap() to disable the interface with fewer operations.
It should be noted that ever since
commit 685d958e38 (MDEV-14425)
most 64-bit Linux platforms on our CI platforms
(s390x a.k.a. IBM System Z being a notable exception) read and write
/dev/shm/*/ib_logfile0 via a memory mapping, pretending that it is
persistent memory (mount -o dax). So, the memory mapping based log
parsing that this change is enabling by default on Linux and FreeBSD
has already been extensively tested on Linux.
::log_mmap(): If a log cannot be opened as PMEM and the desired access
is read-only, try to open a read-only memory mapping.
xtrabackup_copy_mmap_snippet(), xtrabackup_copy_mmap_logfile():
Copy the InnoDB log in mariadb-backup --backup from a memory
mapped file.
The issue is caused by a race between buf_page_create_low getting the
page from buffer pool hash and buf_LRU_free_page evicting it from LRU.
The issue is introduced in 10.6 by MDEV-27058
commit aaef2e1d8c
MDEV-27058: Reduce the size of buf_block_t and buf_page_t
The solution is buffer fix the page before releasing buffer pool mutex
in buf_page_create_low when x_lock_try fails to acquire the page latch.
buf_page_t::read_complete(): Fix an incorrect condition that had been
added in commit aaef2e1d8c (MDEV-27058).
Also for compressed-only pages we must remember that buffered changes
may exist.
buf_read_page(): Correct the function comment; this is for a synchronous
and not asynchronous read. Pass the parameter unzip=true to
buf_read_page_low(), because each of our callers will be interested in
the uncompressed page frame. This will cause the test
encryption.innodb-compressed-blob to emit more errors when the
correct keys for decrypting the clustered index root page are unavailable.
Reviewed by: Debarun Banerjee
buf_pool_t::page_fix(): If a change buffer merge may be needed on a
ROW_FORMAT=COMPRESSED page that exists in compressed-only format in
the buffer pool, go ahead to decompress the block. This fixes an
infinite loop.
Reviewed by: Debarun Banerjee
