Remove incorrect BF (brute force) handling from lock_rec_has_to_wait_in_queue
and move condition to correct callers. Add a function to report
BF lock waits and assert if incorrect BF-BF lock wait happens.
wsrep_report_bf_lock_wait
Add a new function to report BF lock wait.
wsrep_assert_no_bf_bf_wait
Add a new function to check do we have a
BF-BF wait and if we have report this case
and assert as it is a bug.
lock_rec_has_to_wait
Use new wsrep_assert_bf_wait to check BF-BF wait.
lock_rec_create_low
lock_table_create
Use new function to report BF lock waits.
lock_rec_insert_by_trx_age
lock_grant_and_move_on_page
lock_grant_and_move_on_rec
Assert that trx is not Galera as VATS is not compatible
with Galera.
lock_rec_add_to_queue
If there is conflicting lock in a queue make sure that
transaction is BF.
lock_rec_has_to_wait_in_queue
Remove incorrect BF handling. If there is conflicting
locks in a queue all transactions must wait.
lock_rec_dequeue_from_page
lock_rec_unlock
If there is conflicting lock make sure it is not
BF-BF case.
lock_rec_queue_validate
Add Galera record locking rules comment and use
new function to report BF lock waits.
All attempts to reproduce the original assertion have been
failed. Therefore, there is no test case on this commit.
This follows up MDEV-14374, which was filed against MariaDB Server 10.3.
Back then, on a 48-core Qualcomm Centriq 2400, the performance of
delay loops for spinloops was tested both with and without the dummy
compare-and-swap operation, and it was decided to keep the dummy
operation.
On target architectures where nothing special is available (other than
x86 (IA-32, AMD64) or POWER), we perform a dummy compare-and-swap operation.
This is contrary to the idea of the x86 PAUSE instruction and the
__ppc_get_timebase(), which aim to keep the memory bus idle for a while,
to allow other cores to better execute code while a spinloop is waiting
for something to be changed.
On MariaDB Server 10.4 and another implementation of the ARMv8 ISA,
omitting the dummy compare-and-swap improved performance by up to 12%.
So, let us avoid the dummy compare-and-swap on ARM.
For now, we are retaining the dummy compare-and-swap on other ISAs
(such as SPARC, MIPS, S390x, RISC-V) because we do not have any
performance data for them.
In 10.3, DBUG_ASSERT() may expand to something that includes
__builtin_expect(), which expects integer arguments, not pointers.
To avoid any compiler warnings, let us use an explicit rather than
implicit comparison to the null pointer.
Due to restricted size of the threadpool, execution of client queries can
be delayed (queued) for a while. This delay was interpreted as client
inactivity, and connection is closed, if client idle time + queue time
exceeds wait_timeout.
But users did not expect queue time to be included into wait_timeout.
This patch changes the behavior. We don't close connection anymore,
if there is some unread data present on connection,
even if wait_timeout is exceeded. Unread data means that client
was not idle, it sent a query, which we did not have time to process yet.
aarch64 timer is available to userspace via arch register.
clang's __builtin_readcyclecounter is wrong for aarch64 (reads the PMU
cycle counter instead of the archi-timer register), so we don't use it.
my_rdtsc unit-test on AWS m6g shows:
frequency: 121830845
resolution: 1
overhead: 1
This counter is not strictly increasing, but it is non-decreasing.
In fsp_path_to_space_name(), we would access a byte right before
the start of the string, tripping AddressSanitizer.
This reverts commit d87006a1c1
and commit a7634281aa.
This version is not optimized yet. It could have bugs because I didn't
check it with unit tests. Also, std::char_traits are not really supported.
So, now it's not possible to create f.ex. a case insensitive string_view.
fil_path_to_space_name(): renamed, moved to another file
and refactored to use string_view
accept might return an error, including SOCKET_EAGAIN/
SOCKET_EINTR. The caller, usually handle_connections_sockets
can these however and invalid file descriptor isn't something
to call fcntl on.
Thanks to Etienne Guesnet (ATOS) for diagnosis,
sample patch description and testing.
In AddressSanitizer, we only want memory poisoning to happen
in connection with custom memory allocation or freeing.
The primary use of MEM_UNDEFINED is for declaring memory uninitialized
in Valgrind or MemorySanitizer. We do not want MEM_UNDEFINED to
have the unwanted side effect that AddressSanitizer would no longer
be able to complain about accessing unallocated memory.
MEM_UNDEFINED(): Define as no-op for AddressSanitizer.
MEM_MAKE_ADDRESSABLE(): Define as MEM_UNDEFINED() or
ASAN_UNPOISON_MEMORY_REGION().
MEM_CHECK_ADDRESSABLE(): Wrap also __asan_region_is_poisoned().
- Some of the bug fixes are backports from 10.5!
- The fix in innobase/fil/fil0fil.cc is just a backport to get less
error messages in mysqld.1.err when running with valgrind.
- Renamed HAVE_valgrind_or_MSAN to HAVE_valgrind
MemorySanitizer (clang -fsanitize=memory) requires that all code
be compiled with instrumentation enabled. The only exception is the
C runtime library. Failure to use instrumented libraries will cause
bogus messages about memory being uninitialized.
In WITH_MSAN builds, we must avoid calling getservbyname(),
because even though it is a standard library function, it is
not instrumented, not even in clang 10.
Note: Before MariaDB Server 10.5, ./mtr will typically fail
due to the old PCRE library, which was updated in MDEV-14024.
The following cmake options were tested on 10.5
in commit 94d0bb4dbe:
cmake \
-DCMAKE_C_FLAGS='-march=native -O2' \
-DCMAKE_CXX_FLAGS='-stdlib=libc++ -march=native -O2' \
-DWITH_EMBEDDED_SERVER=OFF -DWITH_UNIT_TESTS=OFF -DCMAKE_BUILD_TYPE=Debug \
-DWITH_INNODB_{BZIP2,LZ4,LZMA,LZO,SNAPPY}=OFF \
-DPLUGIN_{ARCHIVE,TOKUDB,MROONGA,OQGRAPH,ROCKSDB,CONNECT,SPIDER}=NO \
-DWITH_SAFEMALLOC=OFF \
-DWITH_{ZLIB,SSL,PCRE}=bundled \
-DHAVE_LIBAIO_H=0 \
-DWITH_MSAN=ON
MEM_MAKE_DEFINED(): An alias for VALGRIND_MAKE_MEM_DEFINED()
and __msan_unpoison().
MEM_GET_VBITS(), MEM_SET_VBITS(): Aliases for
VALGRIND_GET_VBITS(), VALGRIND_SET_VBITS(), __msan_copy_shadow().
InnoDB: Replace the UNIV_MEM_ macros with corresponding MEM_ macros.
ut_crc32_8_hw(), ut_crc32_64_low_hw(): Use the compiler built-in
functions instead of inline assembler when building WITH_MSAN.
This will require at least -msse4.2 when building for IA-32 or AMD64.
The inline assembler would not be instrumented, and would thus cause
bogus failures.
When high priority replication slave applier encounters lock conflict in innodb,
it will force the conflicting lock holder transaction (victim) to rollback.
This is a must in multi-master sychronous replication model to avoid cluster lock-up.
This high priority victim abort (aka "brute force" (BF) abort), is started
from innodb lock manager while holding the victim's transaction's (trx) mutex.
Depending on the execution state of the victim transaction, it may happen that the
BF abort will call for THD::awake() to wake up the victim transaction for the rollback.
Now, if BF abort requires THD::awake() to be called, then the applier thread executed
locking protocol of: victim trx mutex -> victim THD::LOCK_thd_data
If, at the same time another DBMS super user issues KILL command to abort the same victim,
it will execute locking protocol of: victim THD::LOCK_thd_data -> victim trx mutex.
These two locking protocol acquire mutexes in opposite order, hence unresolvable mutex locking
deadlock may occur.
The fix in this commit adds THD::wsrep_aborter flag to synchronize who can kill the victim
This flag is set both when BF is called for from innodb and by KILL command.
Either path of victim killing will bail out if victim's wsrep_killed is already
set to avoid mutex conflicts with the other aborter execution. THD::wsrep_aborter
records the aborter THD's ID. This is needed to preserve the right to kill
the victim from different locations for the same aborter thread.
It is also good error logging, to see who is reponsible for the abort.
A new test case was added in galera.galera_bf_kill_debug.test for scenario where
wsrep applier thread and manual KILL command try to kill same idle victim
The idea was borrowed from http://wg21.link/p0052
scope_exit class is a helper, its name is hidden from user in
the namespace detail.
Alternative implementation of scope_exit with std::function
looks slower on goldbolt.org as it may require allocation, etc.
scope_exit doesn't need to own a callable, so beeing a pointer
is enough. And std::decay produces such a pointer from callable.
MDEV-21298: mariabackup doesn't read from the [mariadbd] and [mariadbd-X.Y]
server option groups from configuration files
MDEV-21301: mariabackup doesn't read [mariadb-backup] option group in
configuration file
All three issues require to change the same code, that is why their
fixes are joined in one commit.
The fix is in invoking load_defaults_or_exit() and handle_options() for
backup-specific groups separately from client-server groups to let the last
handle_options() call fail on unknown backup-specific options.
The order of options procesing is the following:
1) Load server groups and process server options, ignore unknown
options
2) Load client groups and process client options, ignore unknown
options
3) Load backup groups and process client-server options, exit on
unknown option
4) Process --mysqld-args command line options, ignore unknown options
New global flag my_handle_options_init_variables was added to have
ability to invoke handle_options() for the same allowed options set
several times without re-initialising previously set option values.
--password value destroying is moved from option processing callback to
mariabackup's handle_options() function to have ability to invoke server's
handle_options() several times for the same possible allowed options
set.
Galera invokes wsrep_sst_mariabackup.sh with mysqld command line
options to configure mariabackup as close to the server as possible.
It is not known what server options are supported by mariabackup when the
script is invoked. That is why new mariabackup option "--mysqld-args" is added,
all unknown options that follow this option will be silently ignored.
wsrep_sst_mariabackup.sh was also changed to:
- use "--mysqld-args" mariabackup option to pass mysqld options,
- remove deprecated innobackupex mode,
- remove unsupported mariabackup options:
--encrypt
--encrypt-key
--rebuild-indexes
--rebuild-threads
Compiler tells something about argument-dependent lookup. I do not
understand how that ADL works. But I know that such operators should
be free functions, instead of methods:
http://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#Ro-symmetric
Such syntax defines 'friend' free functions.
Introduce a new ATTRIBUTE_NOINLINE to
ib::logger member functions, and add UNIV_UNLIKELY hints to callers.
Also, remove some crash reporting output. If needed, the
information will be available using debugging tools.
Furthermore, remove some fts_enable_diag_print output that included
indexed words in raw form. The code seemed to assume that words are
NUL-terminated byte strings. It is not clear whether a NUL terminator
is always guaranteed to be present. Also, UCS2 or UTF-16 strings would
typically contain many NUL bytes.
