Backport pull request #125 from grooverdan/MDEV-8923_innodb_buffer_pool_dump_pct to 10.0
WL#6504 InnoDB buffer pool dump/load enchantments
This patch consists of two parts:
1. Dump only the hottest N% of the buffer pool(s)
2. Prevent hogging the server duing BP load
From MySQL - commit b409342c43ce2edb68807100a77001367c7e6b8e
Add testcases for innodb_buffer_pool_dump_pct_basic.
Part of the code authored by Daniel Black
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 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 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.
InnoDB: Failing assertion: mutex_own(&buf_pool->LRU_list_mutex)
and
InnoDB: Assertion failure in thread 2868898624 in file buf0lru.c line 1077
InnoDB: Failing assertion: mutex_own(&buf_pool->LRU_list_mutex)
Analysis: Function buf_LRU_free_block might release LRU_list_mutex on
same cases to avoid mutex order problems, we need to take it back
before accessing list.
config.h.cmake:
define NOMINMAX, otherwise Windows system headers define min() and max() macros
sql/slave.cc:
mi->report() has one more argument in MariaDB
storage/xtradb/buf/buf0flu.cc:
xtradb fixes for windows, again
buf0flu.cc line 549.
Analysis: If buf_page_get_state(bpage) == BUF_BLOCK_REMOVE_HASH then
buf_page_in_file(bpage) might not be true.
Fix: ut_a(buf_page_in_file(bpage) || buf_page_get_state(bpage) == BUF_BLOCK_REMOVE_HASH);
4229: MDEV-5670: Assertion failure in file buf0lru.c line 2355
Add more status information if repeatable.
4230: MDEV-5673: Crash while parallel dropping multiple tables under heavy load
Improve long semaphore wait output to include all semaphore waits
and try to find out if there is a sequence of waiters.
4233: Fix compiler errors on product build.
4237: Fix too agressive long semaphore wait output and add guard against introducing
compression failures on insert buffer.
4238: Fix test failure caused by simulated compression failure on
IBUF_DUMMY table.
Analysis: Based on crashed the buffer pool instance identifier is
not correct on block to be freed. Add LRU list mutex holding
on functions calling free and add additional safety checks.
when compressed tables are used.
Analysis: Number of flushed pages is incorrectly calculated at
buf_do_LRU_batch. This leads to problem when utility function
flushes dirty blocks from the end of the flush list of
all buffer pool instances in a loop until enough pages are flushed
or time limit is reached. As number of flushed pages is incorrectly
calculated, the loop mostly try to flush until time limit is
reached because the number of pages limit is not reached.
Fix: Fix the calculation of flushed pages (very short). This fix
was provided by Alexey Stroganov (Percona).
Analysis: XtraDB merge regression, at the end of mutex_spin_wait before goto mutex_loop
there is missing
if (prio_mutex) {
os_atomic_decrement_ulint(&prio_mutex->high_priority_waiters, 1);
}
Hence we get unbalanced waiter count.
Thanks to Laurynas Biveinis for finding this.
