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32 commits

Author SHA1 Message Date
Marko Mäkelä
ba573c4736 MDEV-21133 follow-up: More my_assume_aligned hints
fsp0pagecompress.h: Remove.
Invoke fil_page_get_type() and FSP_FLAGS_GET_PAGE_COMPRESSION_LEVEL
directly.

log_block_get_flush_bit(), log_block_set_flush_bit():
Access the byte directly.

dict_sys_read_row_id(): Remove (unused function).
2020-05-07 12:25:00 +03:00
Oleksandr Byelkin
c07325f932 Merge branch '10.3' into 10.4 2019-05-19 20:55:37 +02:00
Marko Mäkelä
26a14ee130 Merge 10.1 into 10.2 2019-05-13 17:54:04 +03:00
Vicențiu Ciorbaru
cb248f8806 Merge branch '5.5' into 10.1 2019-05-11 22:19:05 +03:00
Marko Mäkelä
6b6fa3cdb1 MDEV-18644: Support full_crc32 for page_compressed
This is a follow-up task to MDEV-12026, which introduced
innodb_checksum_algorithm=full_crc32 and a simpler page format.
MDEV-12026 did not enable full_crc32 for page_compressed tables,
which we will be doing now.

This is joint work with Thirunarayanan Balathandayuthapani.

For innodb_checksum_algorithm=full_crc32 we change the
page_compressed format as follows:

FIL_PAGE_TYPE: The most significant bit will be set to indicate
page_compressed format. The least significant bits will contain
the compressed page size, rounded up to a multiple of 256 bytes.

The checksum will be stored in the last 4 bytes of the page
(whether it is the full page or a page_compressed page whose
size is determined by FIL_PAGE_TYPE), covering all preceding
bytes of the page. If encryption is used, then the page will
be encrypted between compression and computing the checksum.
For page_compressed, FIL_PAGE_LSN will not be repeated at
the end of the page.

FSP_SPACE_FLAGS (already implemented as part of MDEV-12026):
We will store the innodb_compression_algorithm that may be used
to compress pages. Previously, the choice of algorithm was written
to each compressed data page separately, and one would be unable
to know in advance which compression algorithm(s) are used.

fil_space_t::full_crc32_page_compressed_len(): Determine if the
page_compressed algorithm of the tablespace needs to know the
exact length of the compressed data. If yes, we will reserve and
write an extra byte for this right before the checksum.

buf_page_is_compressed(): Determine if a page uses page_compressed
(in any innodb_checksum_algorithm).

fil_page_decompress(): Pass also fil_space_t::flags so that the
format can be determined.

buf_page_is_zeroes(): Check if a page is full of zero bytes.

buf_page_full_crc32_is_corrupted(): Renamed from
buf_encrypted_full_crc32_page_is_corrupted(). For full_crc32,
we always simply validate the checksum to the page contents,
while the physical page size is explicitly specified by an
unencrypted part of the page header.

buf_page_full_crc32_size(): Determine the size of a full_crc32 page.

buf_dblwr_check_page_lsn(): Make this a debug-only function, because
it involves potentially costly lookups of fil_space_t.

create_table_info_t::check_table_options(),
ha_innobase::check_if_supported_inplace_alter(): Do allow the creation
of SPATIAL INDEX with full_crc32 also when page_compressed is used.

commit_cache_norebuild(): Preserve the compression algorithm when
updating the page_compression_level.

dict_tf_to_fsp_flags(): Set the flags for page compression algorithm.
FIXME: Maybe there should be a table option page_compression_algorithm
and a session variable to back it?
2019-03-18 14:08:43 +02:00
Thirunarayanan Balathandayuthapani
c0f47a4a58 MDEV-12026: Implement innodb_checksum_algorithm=full_crc32
MariaDB data-at-rest encryption (innodb_encrypt_tables)
had repurposed the same unused data field that was repurposed
in MySQL 5.7 (and MariaDB 10.2) for the Split Sequence Number (SSN)
field of SPATIAL INDEX. Because of this, MariaDB was unable to
support encryption on SPATIAL INDEX pages.

Furthermore, InnoDB page checksums skipped some bytes, and there
are multiple variations and checksum algorithms. By default,
InnoDB accepts all variations of all algorithms that ever existed.
This unnecessarily weakens the page checksums.

We hereby introduce two more innodb_checksum_algorithm variants
(full_crc32, strict_full_crc32) that are special in a way:
When either setting is active, newly created data files will
carry a flag (fil_space_t::full_crc32()) that indicates that
all pages of the file will use a full CRC-32C checksum over the
entire page contents (excluding the bytes where the checksum
is stored, at the very end of the page). Such files will always
use that checksum, no matter what the parameter
innodb_checksum_algorithm is assigned to.

For old files, the old checksum algorithms will continue to be
used. The value strict_full_crc32 will be equivalent to strict_crc32
and the value full_crc32 will be equivalent to crc32.

ROW_FORMAT=COMPRESSED tables will only use the old format.
These tables do not support new features, such as larger
innodb_page_size or instant ADD/DROP COLUMN. They may be
deprecated in the future. We do not want an unnecessary
file format change for them.

The new full_crc32() format also cleans up the MariaDB tablespace
flags. We will reserve flags to store the page_compressed
compression algorithm, and to store the compressed payload length,
so that checksum can be computed over the compressed (and
possibly encrypted) stream and can be validated without
decrypting or decompressing the page.

In the full_crc32 format, there no longer are separate before-encryption
and after-encryption checksums for pages. The single checksum is
computed on the page contents that is written to the file.

We do not make the new algorithm the default for two reasons.
First, MariaDB 10.4.2 was a beta release, and the default values
of parameters should not change after beta. Second, we did not
yet implement the full_crc32 format for page_compressed pages.
This will be fixed in MDEV-18644.

This is joint work with Marko Mäkelä.
2019-02-19 18:50:19 +02:00
Marko Mäkelä
2ca904f0ca MDEV-13103 Deal with page_compressed page corruption
fil_page_decompress(): Replaces fil_decompress_page().
Allow the caller detect errors. Remove
duplicated code. Use the "safe" instead of "fast" variants of
decompression routines.

fil_page_compress(): Replaces fil_compress_page().
The length of the input buffer always was srv_page_size (innodb_page_size).
Remove printouts, and remove the fil_space_t* parameter.

buf_tmp_buffer_t::reserved: Make private; the accessors acquire()
and release() will use atomic memory access.

buf_pool_reserve_tmp_slot(): Make static. Remove the second parameter.
Do not acquire any mutex. Remove the allocation of the buffers.

buf_tmp_reserve_crypt_buf(), buf_tmp_reserve_compression_buf():
Refactored away from buf_pool_reserve_tmp_slot().

buf_page_decrypt_after_read(): Make static, and simplify the logic.
Use the encryption buffer also for decompressing.

buf_page_io_complete(), buf_dblwr_process(): Check more failures.

fil_space_encrypt(): Simplify the debug checks.

fil_space_t::printed_compression_failure: Remove.

fil_get_compression_alg_name(): Remove.

fil_iterate(): Allocate a buffer for compression and decompression
only once, instead of allocating and freeing it for every page
that uses compression, during IMPORT TABLESPACE. Also, validate the
page checksum before decryption, and reduce the scope of some variables.

fil_page_is_index_page(), fil_page_is_lzo_compressed(): Remove (unused).

AbstractCallback::operator()(): Remove the parameter 'offset'.
The check for it in FetchIndexRootPages::operator() was basically
redundant and dead code since the previous refactoring.
2018-06-14 14:23:01 +03:00
Marko Mäkelä
f5eb37129f MDEV-13103 Deal with page_compressed page corruption
fil_page_decompress(): Replaces fil_decompress_page().
Allow the caller detect errors. Remove
duplicated code. Use the "safe" instead of "fast" variants of
decompression routines.

fil_page_compress(): Replaces fil_compress_page().
The length of the input buffer always was srv_page_size (innodb_page_size).
Remove printouts, and remove the fil_space_t* parameter.

buf_tmp_buffer_t::reserved: Make private; the accessors acquire()
and release() will use atomic memory access.

buf_pool_reserve_tmp_slot(): Make static. Remove the second parameter.
Do not acquire any mutex. Remove the allocation of the buffers.

buf_tmp_reserve_crypt_buf(), buf_tmp_reserve_compression_buf():
Refactored away from buf_pool_reserve_tmp_slot().

buf_page_decrypt_after_read(): Make static, and simplify the logic.
Use the encryption buffer also for decompressing.

buf_page_io_complete(), buf_dblwr_process(): Check more failures.

fil_space_encrypt(): Simplify the debug checks.

fil_space_t::printed_compression_failure: Remove.

fil_get_compression_alg_name(): Remove.

fil_iterate(): Allocate a buffer for compression and decompression
only once, instead of allocating and freeing it for every page
that uses compression, during IMPORT TABLESPACE.

fil_node_get_space_id(), fil_page_is_index_page(),
fil_page_is_lzo_compressed(): Remove (unused code).
2018-06-14 13:46:07 +03:00
Marko Mäkelä
8f643e2063 Merge 10.1 into 10.2 2017-05-23 11:09:47 +03:00
Jan Lindström
90c52e5291 MDEV-12615: InnoDB page compression method snappy mostly does not compress pages
Snappy compression method require that output buffer
used for compression is bigger than input buffer.
Similarly lzo require additional work memory buffer.
Increase the allocated buffer accordingly.

buf_tmp_buffer_t: removed unnecessary lzo_mem, crypt_buf_free and
comp_buf_free.

buf_pool_reserve_tmp_slot: use alligned_alloc and if snappy
available allocate size based on snappy_max_compressed_length and
if lzo is available increase buffer by LZO1X_1_15_MEM_COMPRESS.

fil_compress_page: Remove unneeded lzo mem (we use same buffer)
and if output buffer is not yet allocated allocate based similarly
as above.

Decompression does not require additional work area.

    Modify test to use same test as other compression method tests.
2017-05-20 21:51:34 +03:00
Marko Mäkelä
f9cc391863 Merge 10.1 into 10.2
This only merges MDEV-12253, adapting it to MDEV-12602 which is already
present in 10.2 but not yet in the 10.1 revision that is being merged.

TODO: Error handling in crash recovery needs to be improved.
If a page cannot be decrypted (or read), we should cleanly abort
the startup. If innodb_force_recovery is specified, we should
ignore the problematic page and apply redo log to other pages.
Currently, the test encryption.innodb-redo-badkey randomly fails
like this (the last messages are from cmake -DWITH_ASAN):

2017-05-05 10:19:40 140037071685504 [Note] InnoDB: Starting crash recovery from checkpoint LSN=1635994
2017-05-05 10:19:40 140037071685504 [ERROR] InnoDB: Missing MLOG_FILE_NAME or MLOG_FILE_DELETE before MLOG_CHECKPOINT for tablespace 1
2017-05-05 10:19:40 140037071685504 [ERROR] InnoDB: Plugin initialization aborted at srv0start.cc[2201] with error Data structure corruption
2017-05-05 10:19:41 140037071685504 [Note] InnoDB: Starting shutdown...
i=================================================================
==5226==ERROR: AddressSanitizer: attempting free on address which was not malloc()-ed: 0x612000018588 in thread T0
    #0 0x736750 in operator delete(void*) (/mariadb/server/build/sql/mysqld+0x736750)
    #1 0x1e4833f in LatchCounter::~LatchCounter() /mariadb/server/storage/innobase/include/sync0types.h:599:4
    #2 0x1e480b8 in LatchMeta<LatchCounter>::~LatchMeta() /mariadb/server/storage/innobase/include/sync0types.h:786:17
    #3 0x1e35509 in sync_latch_meta_destroy() /mariadb/server/storage/innobase/sync/sync0debug.cc:1622:3
    #4 0x1e35314 in sync_check_close() /mariadb/server/storage/innobase/sync/sync0debug.cc:1839:2
    #5 0x1dfdc18 in innodb_shutdown() /mariadb/server/storage/innobase/srv/srv0start.cc:2888:2
    #6 0x197e5e6 in innobase_init(void*) /mariadb/server/storage/innobase/handler/ha_innodb.cc:4475:3
2017-05-05 10:38:53 +03:00
Marko Mäkelä
0871a00a62 MDEV-12545 Reduce the amount of fil_space_t lookups
buf_flush_write_block_low(): Acquire the tablespace reference once,
and pass it to lower-level functions. This is only a start; further
calls may be removed.

fil_decompress_page(): Remove unsafe use of fil_space_get_by_id().
2017-04-21 18:12:10 +03:00
Marko Mäkelä
996c7d5cb5 MDEV-12545 Reduce the amount of fil_space_t lookups
buf_flush_write_block_low(): Acquire the tablespace reference once,
and pass it to lower-level functions. This is only a start; further
calls may be removed later.
2017-04-21 17:47:23 +03:00
Marko Mäkelä
b05bf8ff0f Merge 10.1 to 10.2.
Most notably, this includes MDEV-11623, which includes a fix and
an upgrade procedure for the InnoDB file format incompatibility
that is present in MariaDB Server 10.1.0 through 10.1.20.

In other words, this merge should address
MDEV-11202 InnoDB 10.1 -> 10.2 migration does not work
2017-01-19 12:06:13 +02:00
Marko Mäkelä
ab1e6fefd8 MDEV-11623 MariaDB 10.1 fails to start datadir created with
MariaDB 10.0/MySQL 5.6 using innodb-page-size!=16K

The storage format of FSP_SPACE_FLAGS was accidentally broken
already in MariaDB 10.1.0. This fix is bringing the format in
line with other MySQL and MariaDB release series.

Please refer to the comments that were added to fsp0fsp.h
for details.

This is an INCOMPATIBLE CHANGE that affects users of
page_compression and non-default innodb_page_size. Upgrading
to this release will correct the flags in the data files.
If you want to downgrade to earlier MariaDB 10.1.x, please refer
to the test innodb.101_compatibility how to reset the
FSP_SPACE_FLAGS in the files.

NOTE: MariaDB 10.1.0 to 10.1.20 can misinterpret
uncompressed data files with innodb_page_size=4k or 64k as
compressed innodb_page_size=16k files, and then probably fail
when trying to access the pages. See the comments in the
function fsp_flags_convert_from_101() for detailed analysis.

Move PAGE_COMPRESSION to FSP_SPACE_FLAGS bit position 16.
In this way, compressed innodb_page_size=16k tablespaces will not
be mistaken for uncompressed ones by MariaDB 10.1.0 to 10.1.20.

Derive PAGE_COMPRESSION_LEVEL, ATOMIC_WRITES and DATA_DIR from the
dict_table_t::flags when the table is available, in
fil_space_for_table_exists_in_mem() or fil_open_single_table_tablespace().
During crash recovery, fil_load_single_table_tablespace() will use
innodb_compression_level for the PAGE_COMPRESSION_LEVEL.

FSP_FLAGS_MEM_MASK: A bitmap of the memory-only fil_space_t::flags
that are not to be written to FSP_SPACE_FLAGS. Currently, these will
include PAGE_COMPRESSION_LEVEL, ATOMIC_WRITES and DATA_DIR.

Introduce the macro FSP_FLAGS_PAGE_SSIZE(). We only support
one innodb_page_size for the whole instance.

When creating a dummy tablespace for the redo log, use
fil_space_t::flags=0. The flags are never written to the redo log files.

Remove many FSP_FLAGS_SET_ macros.

dict_tf_verify_flags(): Remove. This is basically only duplicating
the logic of dict_tf_to_fsp_flags(), used in a debug assertion.

fil_space_t::mark: Remove. This flag was not used for anything.

fil_space_for_table_exists_in_mem(): Remove the unnecessary parameter
mark_space, and add a parameter for table flags. Check that
fil_space_t::flags match the table flags, and adjust the (memory-only)
flags based on the table flags.

fil_node_open_file(): Remove some redundant or unreachable conditions,
do not use stderr for output, and avoid unnecessary server aborts.

fil_user_tablespace_restore_page(): Convert the flags, so that the
correct page_size will be used when restoring a page from the
doublewrite buffer.

fil_space_get_page_compressed(), fsp_flags_is_page_compressed(): Remove.
It suffices to have fil_space_is_page_compressed().

FSP_FLAGS_WIDTH_DATA_DIR, FSP_FLAGS_WIDTH_PAGE_COMPRESSION_LEVEL,
FSP_FLAGS_WIDTH_ATOMIC_WRITES: Remove, because these flags do not
exist in the FSP_SPACE_FLAGS but only in memory.

fsp_flags_try_adjust(): New function, to adjust the FSP_SPACE_FLAGS
in page 0. Called by fil_open_single_table_tablespace(),
fil_space_for_table_exists_in_mem(), innobase_start_or_create_for_mysql()
except if --innodb-read-only is active.

fsp_flags_is_valid(ulint): Reimplement from the scratch, with
accurate comments. Do not display any details of detected
inconsistencies, because the output could be confusing when
dealing with MariaDB 10.1.x data files.

fsp_flags_convert_from_101(ulint): Convert flags from buggy
MariaDB 10.1.x format, or return ULINT_UNDEFINED if the flags
cannot be in MariaDB 10.1.x format.

fsp_flags_match(): Check the flags when probing files.
Implemented based on fsp_flags_is_valid()
and fsp_flags_convert_from_101().

dict_check_tablespaces_and_store_max_id(): Do not access the
page after committing the mini-transaction.

IMPORT TABLESPACE fixes:

AbstractCallback::init(): Convert the flags.

FetchIndexRootPages::operator(): Check that the tablespace flags match the
table flags. Do not attempt to convert tablespace flags to table flags,
because the conversion would necessarily be lossy.

PageConverter::update_header(): Write back the correct flags.
This takes care of the flags in IMPORT TABLESPACE.
2017-01-15 19:05:50 +02:00
Sergei Golubchik
ed008a74cf Make atomic writes general
- Atomic writes are enabled by default
- Automatically detect if device supports atomic write and use it if
  atomic writes are enabled
- Remove ATOMIC WRITE options from CREATE TABLE
  - Atomic write is a device option, not a table options as the table may
    crash if the media changes
- Add support for SHANNON SSD cards
2017-01-11 09:18:35 +02:00
Sergei Golubchik
4a5d25c338 Merge branch '10.1' into 10.2 2016-12-29 13:23:18 +01:00
Marko Mäkelä
cdaa1d768e MDEV-11349 (1/2) Fix some clang 4.0 warnings
In functions that declare pointer parameters as nonnull,
remove nullness checks, because GCC would optimize them away anyway.

Use #ifdef instead of #if when checking for a configuration flag.

Clang says that left shifts of negative values are undefined.
So, use ~0U instead of ~0 in a number of macros.

Some functions that were defined as UNIV_INLINE were declared as
UNIV_INTERN. Consistently use the same type of linkage.

ibuf_merge_or_delete_for_page() could pass bitmap_page=NULL to
buf_page_print(), conflicting with the __attribute__((nonnull)).
2016-11-25 12:43:34 +02:00
Marko Mäkelä
8da33e3a86 MDEV-11349 (1/2) Fix some clang 4.0 warnings
In InnoDB and XtraDB functions that declare pointer parameters as nonnull,
remove nullness checks, because GCC would optimize them away anyway.

Use #ifdef instead of #if when checking for a configuration flag.

Clang says that left shifts of negative values are undefined.
So, use ~0U instead of ~0 in a number of macros.

Some functions that were defined as UNIV_INLINE were declared as
UNIV_INTERN. Consistently use the same type of linkage.

ibuf_merge_or_delete_for_page() could pass bitmap_page=NULL to
buf_page_print(), conflicting with the __attribute__((nonnull)).
2016-11-25 09:09:51 +02:00
Jan Lindström
2e814d4702 Merge InnoDB 5.7 from mysql-5.7.9.
Contains also

MDEV-10547: Test multi_update_innodb fails with InnoDB 5.7

	The failure happened because 5.7 has changed the signature of
	the bool handler::primary_key_is_clustered() const
	virtual function ("const" was added). InnoDB was using the old
	signature which caused the function not to be used.

MDEV-10550: Parallel replication lock waits/deadlock handling does not work with InnoDB 5.7

	Fixed mutexing problem on lock_trx_handle_wait. Note that
	rpl_parallel and rpl_optimistic_parallel tests still
	fail.

MDEV-10156 : Group commit tests fail on 10.2 InnoDB (branch bb-10.2-jan)
  Reason: incorrect merge

MDEV-10550: Parallel replication can't sync with master in InnoDB 5.7 (branch bb-10.2-jan)
  Reason: incorrect merge
2016-09-02 13:22:28 +03:00
Jan Lindström
037b78e5ec MDEV-9242: Innodb reports Assertion failure in file buf0dblwr.cc line 579
Analysis: When pages in doublewrite buffer are analyzed compressed
pages do not have correct checksum.

Fix: Decompress page before checksum is compared. If decompression
fails we still check checksum and corrupted pages are found.
If decompression succeeds, page now contains the original
checksum.
2016-04-29 13:47:49 +03:00
Jan Lindström
f7002c05ae MDEV-8250: InnoDB: Page compressed tables are not compressed and compressed+encrypted tables cause crash
Analysis: Problem is that both encrypted tables and compressed tables use
FIL header offset FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION to store
required metadata. Furhermore, for only compressed tables currently
code skips compression.

Fixes:
- Only encrypted pages store key_version to FIL header offset FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION,
  no need to fix
- Only compressed pages store compression algorithm to FIL header offset FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION,
  no need to fix as they have different page type FIL_PAGE_PAGE_COMPRESSED
- Compressed and encrypted pages now use a new page type FIL_PAGE_PAGE_COMPRESSED_ENCRYPTED and
  key_version is stored on FIL header offset FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION and compression
  method is stored after FIL header similar way as compressed size, so that first
  FIL_PAGE_COMPRESSED_SIZE is stored followed by FIL_PAGE_COMPRESSION_METHOD
- Fix buf_page_encrypt_before_write function to really compress pages if compression is enabled
- Fix buf_page_decrypt_after_read function to really decompress pages if compression is used
- Small style fixes
2015-06-04 09:47:06 +03:00
Jan Lindström
d4aef382fd Fix compiler failure on fallocate function and used flags. 2014-12-03 10:41:52 +02:00
Jan Lindström
b96697d286 MDEV-6648: InnoDB: Add support for 4K sector size if supported
New generation hard drives, SSDs and NVM devices support 4K
sector size. Supported sector size can be found using fstatvfs()
or GetDiskFreeSpace() functions.
2014-10-29 11:07:11 +02:00
Jan Lindström
56c4b016ad Fiix random test failures on fil_decompress_page_2 function.
Analysis: InnoDB writes also files that do not contain FIL-header.
This could lead incorrect analysis on os_fil_read_func function
when it tries to see is page page compressed based on FIL_PAGE_TYPE
field on FIL-header. With bad luck uncompressed page that does
not contain FIL-headed, the byte on FIL_PAGE_TYPE position could
indicate that page is page comrpessed.

Fix: Upper layer must indicate is file space page compressed
or not. If this is not yet known, we need to read the FIL-header
and find it out. Files that we know that are not page compressed
we can always just provide FALSE.
2014-07-25 14:37:10 +03:00
Sergei Golubchik
4e68fafad4 compilation failure on Win64
cannot use &ulint_var (where ulint == unsigned __int64)
where (ulong *) is expected (in uncompress() and in "%lu")
2014-05-26 20:42:06 +02:00
Jan Lindström
b5cdc5adcf Fix some compiler warnings and small errors on code. 2014-05-22 16:31:31 +03:00
Jan Lindström
13c73c31c3 Added support for LZO compression method.
Removed: innodb_use_lz4 configuration parameter

Added: innodb_compression_algorithm configuration parameter
0 = no compression, 1 = ZLIB, 2 = LZ4, 3 = LZO

Fixed issue with incorrect trim calculations
2014-04-15 14:28:25 +03:00
Jan Lindström
7322270a05 Set actual compressed page size also on read code path to buffer pool so
that we can later use it to avoid unnecessary trim operations.
2014-03-04 17:14:08 +02:00
Jan Lindström
58ce55134f Removed some unnecessary assertions to debug build and enhanced the page_compression and page_compression_level fetch. 2014-01-13 15:02:31 +02:00
Jan Lindström
ec8257216e Enhancement: Change atomic_writes table option to enum type. Now every file can either use atomic writes, not use it or use default.
SYNTAX: ATOMIC_WRITES=['DEFAULT','ON','OFF']

Idea here is to be able to define innodb_doublewrite = 1 but with following rules:

ATOMIC_WRITES='DEFAULT' - if innodb_use_atomic_writes = 1, we do not write to doublewrite buffer the changes
                          if innodb_use_atomic_writes = 0, we write to doublewrite buffer
ATOMIC_WRITES='ON'      - do not write to doublewrite buffer
ATOMIC_WRITES='OFF'     - write to doublewrite buffer

Note that doublewrite buffer can't be used if innodb_doublewrite = 0.
2014-01-10 12:11:36 +02:00
Jan Lindström
5e55d1ced5 Changes for Fusion-io multi-threaded flush, page compressed tables and
tables using atomic write/table.

This is work in progress and some parts are at most POC quality.
2013-12-19 14:36:38 +02:00