Fixes the following error when building with gcc 13:
"tpool/aio_liburing.cc:64:18: error: 'runtime_error' is not a member of 'std'
64 | throw std::runtime_error("aio_uring()");"
The resources like uring in MariaDB aren't intended for spawned
processes so we restrict access using the io_uring_ring_dontfork
liburing library call.
aio_uring::thread_routine(): Handle -EINTR from io_uring_wait_cqe()
in the same way as aio_linux::getevent_thread_routine() does it:
simply ignore it and invoke the system call again.
Reviewed by: Vladislav Vaintroub
In commit 49e2c8f0a6 (MDEV-25743)
we made dict_sys_t::find() incompatible with the rest of the
table name hash table operations in case the table name contains
non-ASCII octets (using a compatibility mode that facilitates the
upgrade into the MySQL 5.0 filename-safe encoding) and the target
platform implements signed char.
ut_fold_string(): Remove; replace with my_crc32c(). This also makes
table name hash value calculations independent on whether char
is unsigned or signed.
The server still may abort if there is no enough free space in the
ring buffer to resubmit the IO job, but the behavior is equal to
the failure of os_aio() -> submit_io().
This gives the user the size required and how to set
memlock limits for the process.
Thanks Jens Axboe for providing this requested interface
ref: https://github.com/axboe/liburing/issues/246
Also don't put \n on my_printf_error, its implicit.
liburing is a new optional dependency (WITH_URING=auto|yes|no)
that replaces libaio when it is available.
aio_uring: class which wraps io_uring stuff
aio_uring::bind()/unbind(): optional optimization
aio_uring::submit_io(): mutex prevents data race. liburing calls are
thread-unsafe. But if you look into it's implementation you'll see
atomic operations. They're used for synchronization between kernel and
user-space only. That's why our own synchronization is still needed.
For systemd, we add LimitMEMLOCK=524288 (ulimit -l 524288)
because the io_uring_setup system call that is invoked
by io_uring_queue_init() requests locked memory. The value
was found empirically; with 262144, we would occasionally
fail to enable io_uring when using the maximum values of
innodb_read_io_threads=64 and innodb_write_io_threads=64.
aio_uring::thread_routine(): Tolerate -EINTR return from
io_uring_wait_cqe(), because it may occur on shutdown
on Ubuntu 20.10 (Groovy Gorilla).
This was mostly implemented by Eugene Kosov. Systemd integration
and improved startup/shutdown error handling by Marko Mäkelä.
