Also added support for MAP_SYNC. It allows to achieve decent performance
with DAX devices even when libpmem is unavailable.
Fixed Windows version of my_msync(): according to manual FlushViewOfFile()
may return before flush is actually completed. It is advised to issue
FlushFileBuffers() after FlushViewOfFile().
if my_realpath() fails, don't return the error code, get_defaults_options()
returns a number of options consumed, not 0=ok/1=error.
instead, ignore the error from my_realpath. If it fails it internally
falls back to my_load_path, which restores 10.4- behavior
Use my_thread_var::stack_ends_here inside lf_pinbox_real_free() for address
where thread stack ends.
Remove LF_PINS::stack_ends_here.
It is not safe to assume that mysys_var that was used during pin allocation,
remains correct during free. E.g with binlog group commit in Innodb,
that frees pins for multiple Innodb transactions, it does not work
correctly.
Threadpool will need a functionality for periodic thr_timer
(the threadpool maintainence task is a timer that runs periodically).
Also increase the stack size for the timer thread, 8k won't be enough.
make load_defaults() store the file name in the generated option list
using a special marker ---file-marker--- option.
Pick up this filename in handle_options().
Remove ---args-separator---, use ---file-marker--- with an empty file
name instead - this simplifies checks on the caller, only one special
option to recognize.
only my_getopt should use it, because it changes my_getopt's behavior.
If one simply wants to skip the separator - don't ask it to be added
in the first place
process all --defaults* options uniformly,
get rid of special case for --no-defaults and --print-defaults
use realpath instead of blindly concatenating pwd and relative path.
it turns out that practically every single user of handle_options()
used the get_one_option callback. Simplify the code,
make it mandatory, adjust unit tests.
almost all my_getopt settings and callbacks are global variables,
directly assignable to configure my_getopt. Only getopt_get_addr
was using a setter function. Get rid of it, make it a global
directly assignable variable like all other settings.
Also make getopt_compare_strings() static.
This is a remnant of "MySQL Instance Manager", which was removed in
MySQL-5.5.0 and never existed in MariaDB
Remove callback, simplify and optimize the code accordingly.
Commit 536215e32f in MariaDB Server 10.3.1
introduced the compiler flag (not cmake option) DBUG_ASSERT_AS_PRINTF
that converts DBUG_ASSERT in non-debug builds into printouts.
For debug builds, it could be useful to be able to convert DBUG_ASSERT
into a warning or error printout, to allow execution to continue.
This would allow debug builds to be used for reproducing hard failures
that occur with release builds.
my_assert: A Boolean flag (set by default), tied to the new option
debug_assert that is available on debug builds only.
When set, DBUG_ASSERT() will invoke assert(), like it did until now.
When unset, DBUG_ASSERT() will invoke fprintf(stderr, ...)
with the file name, line number and assertion expression.
Limit increased from 1000 to 2000.
Avoiding stack overflow by only storing keys and pages on the stack in
recursive functions if there is plenty of space on it.
Other things:
- Use less stack space for b-tree operations as we now only allocate as
much space as needed instead of always allocating HA_MAX_KEY_LENGTH.
- Replaced most usage of my_safe_alloca() in Aria with the stack_alloc
interface.
- Moved my_setstacksize() to mysys/my_pthread.c
Even though the PAUSE instruction latency was increased from
about 10 to 140 clock cycles in the Intel Skylake microarchitecture,
it seems to be optimal to reduce the amount of subsequently executed
PAUSE instructions not to 1/14, but to 1/2.
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.
The RDTSC instruction, which was introduced in the Intel Pentium,
has been used in MariaDB for a long time. But, the __rdtsc()
wrapper is not available by default in some x86 build environments.
The simplest solution seems to replace the inlined instruction
with a call to the wrapper function my_timer_cycles(). The overhead
for the call should not affect the measurement threshold.
On Windows and on AMD64, we will keep using __rdtsc() directly.
Starting with the Intel Skylake microarchitecture, the PAUSE
instruction latency is about 140 clock cycles instead of earlier 10.
On AMD processors, the latency could be 10 or 50 clock cycles,
depending on microarchitecture.
Because of this big range of latency, let us scale the loops around
the PAUSE instruction based on timing results at server startup.
my_cpu_relax_multiplier: New variable: How many times to invoke PAUSE
in a loop. Only defined for IA-32 and AMD64.
my_cpu_init(): Determine with RDTSC the time to run 16 PAUSE instructions
in two unrolled loops according, and based on the quicker of the two
runs, initialize my_cpu_relax_multiplier. This form of calibration was
suggested by Mikhail Sinyavin from Intel.
LF_BACKOFF(), ut_delay(): Use my_cpu_relax_multiplier when available.
ut_delay(): Define inline in my_cpu.h.
UT_COMPILER_BARRIER(): Remove. This does not seem to have any effect,
because in our ut_delay() implementation, no computations are being
performed inside the loop. The purpose of UT_COMPILER_BARRIER() was to
prohibit the compiler from reordering computations. It was not
emitting any code.
- Do not scan registry to check if TCPIP is supported.
- Do not read registry under HKEY_LOCAL_MACHINE\SOFTWARE\MySQL anymore.
- Do not load threadpool function dynamically, it is available
since Win7.
- simplify win32_init_tcp_ip(), and return error of WSAStartup() fails.
- Correct comment in my_parameter_handler()