in innodb_read_only mode.
The reason for the hang is that there was no notification received about
completed read io. File handles are bound to completion_port, and there
were no background "write" threads that would be waiting on completion_port,
only 2 "read" threads waiting on read_completion_port were active.
The fix is to use a single IO completion port for all IOs, if
innodb_read_only is set.
Allow 64-bit atomic operations on 32-bit systems,
only relying on HAVE_ATOMIC_BUILTINS_64, disregarding
the width of the register file.
Define UNIV_WORD_SIZE correctly on all systems, including Windows.
In MariaDB 10.0 and 10.1, it was incorrectly defined as 4 on
64-bit Windows.
Define HAVE_ATOMIC_BUILTINS_64 on Windows
(64-bit atomics are available on both 32-bit and 64-bit Windows
platforms; the operations were unnecessarily disabled even on
64-bit Windows).
MONITOR_OS_PENDING_READS, MONITOR_OS_PENDING_WRITES: Enable by default.
os_file_n_pending_preads, os_file_n_pending_pwrites,
os_n_pending_reads, os_n_pending_writes: Remove.
Use the monitor counters instead.
os_file_count_mutex: Remove. On a system that does not support
64-bit atomics, monitor_mutex will be used instead.
The function posix_fallocate() as well as the Linux system call
fallocate() can return EINTR when the operation was interrupted
by a signal. In that case, keep retrying the operation, except
if InnoDB shutdown has been initiated.
a large memory buffer on Windows
fil_extend_space_to_desired_size(), os_file_set_size(): Use calloc()
for memory allocation, and handle failures. Properly check the return
status of posix_fallocate(), and pass the correct arguments to
posix_fallocate().
On Windows, instead of extending the file by at most 1 megabyte at a time,
write a zero-filled page at the end of the file.
According to the Microsoft blog post
https://blogs.msdn.microsoft.com/oldnewthing/20110922-00/?p=9573
this will physically extend the file by writing zero bytes.
(InnoDB never uses DeviceIoControl() to set the file sparse.)
I tested that the file extension works properly with a multi-file
system tablespace, both with --innodb-use-fallocate and
--skip-innodb-use-fallocate (the default):
./mtr \
--mysqld=--innodb-use-fallocate \
--mysqld=--innodb-autoextend-increment=1 \
--mysqld=--innodb-data-file-path='ibdata1:5M;ibdata2:5M:autoextend' \
--parallel=auto --force --retry=0 --suite=innodb &
ls -lsh mysql-test/var/*/mysqld.1/data/ibdata2
(several samples while running the test)
The function trx_purge_stop() was calling os_event_reset(purge_sys->event)
before calling rw_lock_x_lock(&purge_sys->latch). The os_event_set()
call in srv_purge_coordinator_suspend() is protected by that X-latch.
It would seem a good idea to consistently protect both os_event_set()
and os_event_reset() calls with a common mutex or rw-lock in those
cases where os_event_set() and os_event_reset() are used
like condition variables, tied to changes of shared state.
For each os_event_t, we try to document the mutex or rw-lock that is
being used. For some events, frequent calls to os_event_set() seem to
try to avoid hangs. Some events are never waited for infinitely, only
timed waits, and os_event_set() is used for early termination of these
waits.
os_aio_simulated_put_read_threads_to_sleep(): Define as a null macro
on other systems than Windows. TODO: remove this altogether and disable
innodb_use_native_aio on Windows.
os_aio_segment_wait_events[]: Initialize only if innodb_use_native_aio=0.
available space on disk
Add error handling when disk full situation happens and
intentionally bring server down with stacktrace because
on all cases InnoDB can't continue anyway.
Analysis: For some reason actual thread handle is not
returned on Windows instead lpThreadId was returned and
thread handle was closed after thread create. Later
CloseHandle was called for recv_writer_thread_handle
and psort_info->thread_hdl.
Fix: Return thread handle from os_thread_create()
also on Windows and store these thread handles also
in srv0start.cc so that they can be later closed.
after Operating system error number 36 in a file operation.
Analysis: os_file_get_status did not handle error ENAMETOOLONG
correctly.
Fix: Add correct handling for error ENAMETOOLONG. Note that on InnoDB
case the error is not passed all the way up to server. That would
be bigger rewamp.
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.
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.
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.
