Problem is that page compressed tables currently require atomic_blobs and
that feature is not availabe currently for row_format=redundant.
Fix: Disallow page compressed create option if table row_format=redundant.
The bug was that full memory barrier was missing in the code that ensures that
a waiter on an InnoDB mutex will not go to sleep unless it is guaranteed to be
woken up again by another thread currently holding the mutex. This made
possible a race where a thread could get stuck waiting for a mutex that is in
fact no longer locked. If that thread was also holding other critical locks,
this could stall the entire server. There is an error monitor thread than can
break the stall, it runs about once per second. But if the error monitor
thread itself got stuck or was not running, then the entire server could hang
infinitely.
This was introduced on i386/amd64 platforms in 5.5.40 and 10.0.13 by an
incorrect patch that tried to fix the similar problem for PowerPC.
This commit reverts the incorrect PowerPC patch, and instead implements a fix
for PowerPC that does not change i386/amd64 behaviour, making PowerPC work
similarly to i386/amd64.
ALTER TABLE: don't fill default values per row, do it once.
And do it in two places - for copy_data_between_tables() and for online ALTER.
Also, run function_defaults test both for MyISAM and for InnoDB.
Merge Facebook commit cd063ab930
authored by Peng Tian from https://github.com/facebook/mysql-5.6
Introduced a new configuration variable innodb_fatal_semaphore_wait_threshold,
it makes the fatal semaphore timeout configurable. Modified original commit
so that no MariaDB server files are changed, instead introduced a new
InnoDB/XtraDB configuration variable.
Its default/min/max vlaues are 600/1/2^32-1 in seconds (it was hardcoded
as 600, now its default value is 600, so the default behavior of this diff
should be no change).
buildbot on work-amd64-valgrind
Fixed issue by finding out first the current used priority
for both treads and using that seeing did we really change
the priority or not.
setting of innodb_io_capacity_max
(a) Changed the behaviour so that if you set innodb_io_capacity to a
value > innodb_io_capacity_max that the value is accepted AND
that innodb_io_capacity_max = innodb_io_capacity * 2.
(b) If someone wants to reduce innodb_io_capacity_max and
reduce it below innodb_io_capacity then innodb_io_capacity
should be reduced to the same level as innodb_io_capacity_max.
In both cases give a warning to user.
Analysis: InnoDB error monitor is responsible to call every second
sync_arr_wake_threads_if_sema_free() to wake up possible hanging
threads if they are missed in mutex_signal_object. This is not
possible if error monitor itself is on mutex/semaphore wait. We
should avoid all unnecessary mutex/semaphore waits on error monitor.
Currently error monitor calls function buf_flush_stat_update()
that calls log_get_lsn() function and there we will try to get
log_sys mutex. Better, solution for error monitor is that in
buf_flush_stat_update() we will try to get lsn with
mutex_enter_nowait() and if we did not get mutex do not update
the stats.
Fix: Use log_get_lsn_nowait() function on buf_flush_stat_update()
function. If returned lsn is 0, we do not update flush stats.
log_get_lsn_nowait() will use mutex_enter_nowait() and if
we get mutex we return a correct lsn if not we return 0.
on work-amd64-valgrind.
Fixed issue by finding out first the current used priority
for both treads and using that seeing did we really change
the priority or not.
Analysis: InnoDB error monitor is responsible to call every second
sync_arr_wake_threads_if_sema_free() to wake up possible hanging
threads if they are missed in mutex_signal_object. This is not
possible if error monitor itself is on mutex/semaphore wait. We
should avoid all unnecessary mutex/semaphore waits on error monitor.
Currently error monitor calls function buf_flush_stat_update()
that calls log_get_lsn() function and there we will try to get
log_sys mutex. Better, solution for error monitor is that in
buf_flush_stat_update() we will try to get lsn with
mutex_enter_nowait() and if we did not get mutex do not update
the stats.
Fix: Use log_get_lsn_nowait() function on buf_flush_stat_update()
function. If returned lsn is 0, we do not update flush stats.
log_get_lsn_nowait() will use mutex_enter_nowait() and if
we get mutex we return a correct lsn if not we return 0.
Merged Facebook commit 617aef9f911d825e9053f3d611d0389e02031225
authored by Inaam Rana to InnoDB storage engine (not XtraDB)
from https://github.com/facebook/mysql-5.6
WL#7047 - Optimize buffer pool list scans and related batch processing
Reduce excessive scanning of pages when doing flush list batches. The
fix is to introduce the concept of "Hazard Pointer", this reduces the
time complexity of the scan from O(n*n) to O.
The concept of hazard pointer is reversed in this work. Academically
hazard pointer is a pointer that the thread working on it will declar
such and as long as that thread is not done no other thread is allowe
do anything with it.
In this WL we declare the pointer as a hazard pointer and then if any
thread attempts to work on it, it is allowed to do so but it has to a
the hazard pointer to the next valid value. We use hazard pointer sol
reverse traversal of lists within a buffer pool instance.
Add an event to control the background flush thread. The background f
thread wait has been converted to an os event timed wait so that it c
signalled by threads that want to kick start a background flush when
buffer pool is running low on free/dirty pages.
Merge Facebook commit 154c579b828a60722a7d9477fc61868c07453d08
and e8f0052f9b112dc786bf9b957ed5b16a5749f7fd authored
by Steaphan Greene from https://github.com/facebook/mysql-5.6
Optimize prefix index queries to skip cluster index lookup when possible.
Currently InnoDB will always fetch the clustered index (primary key
index) for all prefix columns in an index, even when the value of a
particular record is smaller than the prefix length. This change
optimizes that case to use the record from the secondary index and avoid
the extra lookup.
Also adds two status vars that track how effective this is:
innodb_secondary_index_triggered_cluster_reads:
Times secondary index lookup triggered cluster lookup.
innodb_secondary_index_triggered_cluster_reads_avoided:
Times prefix optimization avoided triggering cluster lookup.
Merge Facebook commit 4f3e0343fd2ac3fc7311d0ec9739a8f668274f0d
authored by Steaphan Greene from https://github.com/facebook/mysql-5.6
Adds innodb_idle_flush_pct to enable tuning of the page flushing rate
when the system is relatively idle. We care about this, since doing
extra unnecessary flash writes shortens the lifespan of the flash.
Merge Facebook commit ca40b4417fd224a68de6636b58c92f133703fc68
authored by Steaphan Greene from https://github.com/facebook/mysql-5.6
Change the default value for innodb_log_compressed_pages to false
Logging these pages is a waste. We don't want this to be enabled.
One caution here: If the zlib version used by innodb is changed, but
the running version is still the previous version, and the running
version crashes, it is possible crash recovery could fail.
When crash recovery uses a zlib version at all different than the
version used by the crashed instance, it is possible that a redone
compression could fail, where the original did not, because the new
zlib version compresses the same data to a slightly larger size.
Because of the nature of compression, this is even possible when
upgrading to a version of zlib which actually peforms overall better
compression than the previous version.
If this happens, mysql will fail to recover, since a page split can
not be safely triggered during crash recovery.
So, either the exact zlib version must be controlled between builds,
or these rare recovery failures must be accepted. The cost of
logging these pages is quite high, so we consider this limitation to
be worthwhile.
This failure scenario can not happen if there was a clean shutdown.
This is only relevant to restarting crashed instances, or starting an
instance built via a hot backup too (XtraBackup).
Analysis: fil_extend_space_to_desired_size() does not provide file
node to os_aio(). This failed on Windows only because on Windows
we do not use posix_fallocate() to extend file space.
Fix: Add file node to os_aio() function call and make sure that
we do not use NULL pointer at os_aio_array_reserve_slot(). Additionally,
make sure that we do not use 0 as file_block_size (512 is the minimum).
New generation hard drives, SSDs and NVM devices support 4K
sector size. Supported sector size can be found using fstatvfs()
or GetDiskFreeSpace() functions.
Merged Facebook commit ec1aac68c74f3c1e558d057c4c9fcfe6edbbea93
authored by Steaphan Greene from https://github.com/facebook/mysql-5.6
In C++11, "" is not parsed as before. So "A""B" is not the same as "AB".
Instead, whitespace is required, like: "A" "B"
Merged Facebook commit dd2d11be7aaf3be270e740fb95cbc4eacb52f4d7
authored by Rongrong Zhong from https://github.com/facebook/mysql-5.6
This fixes MySQL Bug #68220 innodb_rows_updated is misleading on slave
http://bugs.mysql.com/bug.php?id=68220
Added innodb_system_rows_read/inserted/updated/deleted counters
that are the equivalent of innodb_rows_* but that only account for
changes made to system databases (mysql, information_schame and
preformance_schema). These counters will be used on slaves to
differentiated the updates made on system databases from those made on
user databases.
innodb_rows_* status counters are not updated when innodb_system_rows_*
are updated.
dd2d11be7a
Merged Facebook commit ecff018632c6db49bad73d9233c3cdc9f41430e9
authored by Steaphan Greene from https://github.com/facebook/mysql-5.6
This change is to fix: http://bugs.mysql.com/62534
This makes innodb_max_dirty_pages_pct a double with min,default,max values
0.001, 75, 99.999.
This also makes innodb_max_dirty_pages_pct_lwm and adaptive_flushing_lwm
doubles, as these sysvars are inter-dependent.
Added more to the BUFFER POOL AND MEMORY section of SHOW INNODB STATUS:
Percent pages dirty: X.X
This is all n_dirty_pages / used_pages
Percent all pages dirty: X.X
This is all n_dirty_pages / all-pages
Max dirty pages percent: X.X
This is innodb_max_dirty_pages_pct
Also changed all of buf from 2 to 3 digits of precision (%.2f -> %.3f).
Merge Facebook commit f981a51a47519b0ba527917887f8adc6df9ae147
authored by Steaphan Greene from https://github.com/facebook/mysql-5.6.
This just moves some structure definitions from inside a
single .cc file to a shared .h file, with a few tweaks to
allow these structures to be shared.
On its own, it should have no actual effect. This is needed later.
Merge Facebook commit 25295d003cb0c17aa8fb756523923c77250b3294
authored by Steaphan Greene from https://github.com/facebook/mysql-5.6
This adds a pointer to the trx to each mtr.
This allows the trx to be accessed in parts of the code
where it was otherwise not available. This is needed later.
Merge Facebook commit 926a077b14b73c14094de7fc7aa913241b801b4d
authored by Inaam Rana from https://github.com/facebook/mysql-5.6.
This is fix for upstream bugs
http://bugs.mysql.com/bug.php?id=71988http://bugs.mysql.com/bug.php?id=70500
page_cleaner should work whether or not there is server activity.
Its iterations become a noop when there is no work to do but we
should not tie it to the server activity.
The page_cleaner thread does spurious background flushing
because of conditional sleep between iterations. The solution
is not to make sleep dependent on server activity etc.
Merged Facebooks commit 6e06bbfa315ffb97d713dd6e672d6054036ddc21
authored by Inaam Rana from https://github.com/facebook/mysql-5.6.
Fixes MySQL bug http://bugs.mysql.com/bug.php?id=72123
lock_timeout thread works in a tight loop waking up every second
and checking for lock_wait_timeout. In addition, when a mysql
thread is forced to wait on a lock, it signals the lock_timeout thread
as well. This call is not required. In a heavily contended workload
each thread going to wait will signal the lock_timeout thread making
it work all the time. As lock_timeout thread scans the array of
waiting threads under lock_sys::wait_mutex which is already very
hot in contneded loads, these extra scans can cause significanct
performance regression.
Also, in various codepaths lock_timeout thread is signalled where
actual intention was to signal the innodb monitor thread.
Merged Facebook commit bdab302a7e3c37da21a1bffe1550cdbe6c906695
by Inaam Rana from https://github.com/facebook/mysql-5.6.
In os_event_wait_time_low() the logic to calculate abs_time
for wait is broken. The bug has been present at least since
5.5. It gets acutely sensitized when sub-second wait intervals
are passed. It is particularly relevant to us because the
page_cleaner thread will mostly request sub-second wait
intervals. This can potentially lead to a near tight loop
behaviour of page_cleaner with much less sleep then what we'd
actually expect.
When UNIV_INTERN is missing in built-in XtraDB, this causes the
innodb_plugin to call the XtraDB version of the function instead
of its own (seen in --embedded-server test failure in Buildbot).
This in turn causes bad things to happen in case of difference
between XtranDB and innodb_plugin.
(lock != ctx->wait_lock)
References: lp:1364840 lp:1280896 - reverted a part of fix for
lp:1280896 (updating a unique key can cause parallel applying to hang )
in revision #4105. This "BF (brute force) lock skipping" caused
regression which surfaced in randgen test for bug lp:1364840
