std version has an advantage of a more convenient units implementation from
std::chrono. Now it's no need to multipy/divide to bring anything to
micro seconds.
Largely based on MySQL commit
75271e51d6
MySQL Ref:
BUG#24566529: BACKPORT BUG#23575445 TO 5.6
(cut)
Also, the PTR_SANE macro which tries to check if a pointer
is invalid (used when printing pointer values in stack traces)
gave false negatives on OSX/FreeBSD. On these platforms we
now simply check if the pointer is non-null. This also removes
a sbrk() deprecation warning when building on OS X. (It was
before only disabled with building using XCode).
Removed execinfo path of MySQL patch that was already included.
sbrk doesn't exist on FreeBSD aarch64.
Removed HAVE_BSS_START based detection and replaced with __linux__
as it doesn't exist on OSX, Solaris or Windows. __bss_start
exists on mutiple Linux architectures.
Tested on FreeBSD and Linux x86_64. Being in FreeBSD ports for 2
years implies a good testing there on all FreeBSD architectures there
too. MySQL-8.0.21 code is functionally identical to original commit.
Detecting the cpus based on sysconf of the online CPUs can significantly
over estimate the number of cpus available.
Wheither via numactl, cgroups, taskset, systemd constraints, docker
containers and probably other mechanisms, the number of threads mysqld
can be run on can be quite less.
As such we use the pthread_getaffinity_np function on Linux and FreeBSD
(identical API) to get the number of CPUs.
The number of CPUs is the default for the thread_pool_size and a too
high default will resulting in large memory usage and high context
switching overhead.
Closes PR #922
On clang, use __builtin_readcyclecounter() when available.
Hinted by Sergey Vojtovich. (This may lead to runtime failure
on ARM systems. The hardware should be available on ARMv8 (AArch64),
but access to it may require special privileges.)
We remove support for the proprietary Sun Microsystems compiler,
and rely on clang or the __GNUC__ assembler syntax instead.
For now, we retain support for IA-64 (Itanium) and 32-bit SPARC,
even though those platforms are likely no longer widely used.
We remove support for clock_gettime(CLOCK_SGI_CYCLE),
because Silicon Graphics ceased supporting IRIX in December 2013.
This was the only cycle timer interface available for MIPS.
On PowerPC, we rely on the GCC 4.8 __builtin_ppc_get_timebase()
(or clang __builtin_readcyclecounter()), which should be equivalent
to the old assembler code on both 64-bit and 32-bit targets.
SIGHUP causes debug info in the error log and reload of
logs/privileges/tables/etc. The server should only do it when
a user intentionally sends SUGHUP, not when a parent terminal gets
disconnected or something.
In particular, not ignoring kernel SIGHUP causes FLUSH PRIVILEGES
at some random point during non-systemd Debian upgrades (Debian
restarts mysqld, debian-start script runs mysql_upgrade in the background,
postinit script ends and kernel sends SIGHUP to all background processes
it has started). And during mysql_upgrade privilege tables aren't
necessarily ready to be reloaded.
cherry-pick f1daf9ce from 10.0 branch
-------------------------------------
Fix build failures caused by new C runtime library
- isnan, snprintf, struct timespec are now defined, attempt to
redefine them leads
- P_tmpdir, tzname are no more defined
- lfind() and lsearch() in lf_hash.c had to be renamed, declaration
conflicts with some C runtime functions with the same name declared in
a header included by stdlib.h
Also fix couple of annoying warnings :
- remove #define NOMINMAX from config.h to avoid "redefined" compiler
warnings(NOMINMAX is already in compile flags)
- disable incremental linker in Debug as well (feature not used much
and compiler crashes often)
Also simplify package building with Wix, require Wix 3.9 or later
(VS2015 is not compatible with old Wix 3.5/3.6)
when func1 calls func2 from DBUG_RETURN, dbug shows the trace as
| > func1
| < func1
| > func2
| < func2
because DBUG_LEAVE happens before func2(). Change that to invoke
DBUG_LEAVE when the local variable goes out of scope. This uses
gcc specific __attribute__((cleanup)).
Fix build failures caused by new C runtime library
- isnan, snprintf, struct timespec are now defined, attempt to
redefine them leads
- P_tmpdir, tzname are no more defined
- lfind() and lsearch() in lf_hash.c had to be renamed, declaration
conflicts with some C runtime functions with the same name declared in
a header included by stdlib.h
Also fix couple of annoying warnings :
- remove #define NOMINMAX from config.h to avoid "redefined" compiler
warnings(NOMINMAX is already in compile flags)
- disable incremental linker in Debug as well (feature not used much
and compiler crashes often)
Also simplify package building with Wix, require Wix 3.9 or later
(VS2015 is not compatible with old Wix 3.5/3.6)
in cmake tests let's treat clang like gcc (same options,
same builtins) in many cases.
* don't check the compiler when
* testing for -fvisibility=hidden support
* testing for HAVE_ABI_CXA_DEMANGLE
* testing for HAVE_GCC_ATOMIC_BUILTINS
* when removing options with string(replace)
* when running ${CC} --version (ignore the error instead)
* run ABI checks for clang
* use "canonical" gcc flags for clang
* fix groonga too
Also:
* add cmake detection for gcc __atomic_* builtins. they might be
supported (__ATOMIC_SEQ_CST is defined), but not for all operand
sizes. In particular, 64-bit atomic load is problematic on i386
* cache check results for Windows
* remove the test for HAVE_CXXABI_H (HAVE_ABI_CXA_DEMANGLE is
suffifient)
Problem: For every event read, mysqlbinlog calls localtime() which in turn
calls stat(/etc/localtime) which is causing kernel mutex contention.
Analysis and Fix:
localtime() calls stat(/etc/localtime) for every instance of the call
where as localtime_r() the reentrant version was optimized to store
the read only tz internal structure. Hence it will not call
stat(/etc/localtime). It will call only once at the beginning.
The mysql server is calling localtime_r() and mysqlbinlog tool is
one place where we are still using localtime().
Once the process (mysqlbinlog) is started if timezone is changed
it will be not picked up the the process and it will continue
with the same values as the beginning of the process. This
behavior is in-lined with mysql server.
Also adding localtime_r() and gmtime_r() support for windows.
