The commit cd5808eb introduced a union as a storage for the format
argument passed to the internal API fmt::detail::make_arg. This was done
to solve the issue that the internal API no longer accepted temporary
variables.
However, it's generally better to avoid using internal APIs, as they are
more likely to have breaking changes in the future. Instead, we can use
the public API fmt::dynamic_format_arg_store to dynamically build the
argument list. This API accepts temporary variables, and its behavior is
more stable than the internal API. `libfmt.cmake` is updated to reflect
the change as well.
All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the
BSD-new license. I am contributing on behalf of my employer Amazon Web
Services, Inc.
When using the default innodb_log_buffer_size=2m, mariadb-backup --backup
would spend a lot of time re-reading and re-parsing the log. For reads,
it would be beneficial to memory-map the entire ib_logfile0 to the
address space (typically 48 bits or 256 TiB) and read it from there,
both during --backup and --prepare.
We will introduce the Boolean read-only parameter innodb_log_file_mmap
that will be OFF by default on most platforms, to avoid aggressive
read-ahead of the entire ib_logfile0 in when only a tiny portion would be
accessed. On Linux and FreeBSD the default is innodb_log_file_mmap=ON,
because those platforms define a specific mmap(2) option for enabling
such read-ahead and therefore it can be assumed that the default would
be on-demand paging. This parameter will only have impact on the initial
InnoDB startup and recovery. Any writes to the log will use regular I/O,
except when the ib_logfile0 is stored in a specially configured file system
that is backed by persistent memory (Linux "mount -o dax").
We also experimented with allowing writes of the ib_logfile0 via a
memory mapping and decided against it. A fundamental problem would be
unnecessary read-before-write in case of a major page fault, that is,
when a new, not yet cached, virtual memory page in the circular
ib_logfile0 is being written to. There appears to be no way to tell
the operating system that we do not care about the previous contents of
the page, or that the page fault handler should just zero it out.
Many references to HAVE_PMEM have been replaced with references to
HAVE_INNODB_MMAP.
The predicate log_sys.is_pmem() has been replaced with
log_sys.is_mmap() && !log_sys.is_opened().
Memory-mapped regular files differ from MAP_SYNC (PMEM) mappings in the
way that an open file handle to ib_logfile0 will be retained. In both
code paths, log_sys.is_mmap() will hold. Holding a file handle open will
allow log_t::clear_mmap() to disable the interface with fewer operations.
It should be noted that ever since
commit 685d958e38 (MDEV-14425)
most 64-bit Linux platforms on our CI platforms
(s390x a.k.a. IBM System Z being a notable exception) read and write
/dev/shm/*/ib_logfile0 via a memory mapping, pretending that it is
persistent memory (mount -o dax). So, the memory mapping based log
parsing that this change is enabling by default on Linux and FreeBSD
has already been extensively tested on Linux.
::log_mmap(): If a log cannot be opened as PMEM and the desired access
is read-only, try to open a read-only memory mapping.
xtrabackup_copy_mmap_snippet(), xtrabackup_copy_mmap_logfile():
Copy the InnoDB log in mariadb-backup --backup from a memory
mapped file.
10.5 added contents of cmake/os/FreeBSD.cmake in c991efd9c3.
in the merge to 10.11, d002b1f removed this file.
In the past FreeBSD.cmake was removed in 5369df741b
in the 10.11 branch as no remaining code was needed. The combination
of this and the merge lead to the the file being removed. My assumption is
this was a non-stable branch at the time.
The purpose of this patch is clang doesn't have /usr/local/lib in
the path. As such there are various depedency linkages that will fail.
For example pcre and libfmt.
CMake WSREP=ON has some implications for client
executables so still present this as an option
when compiling WITHOUT_SERVER. In this case
default to ON for maximium compatibility of
the build client executables and libraries.
- ZLIB_LIBRARIES, not ZLIB_LIBRARY
- ZLIB_INCLUDE_DIRS, not ZLIB_INCLUDE_DIR
For building libmariadb, ZLIB_LIBRARY/ZLIB_INCLUDE_DIR are still defined
This workaround will be removed later.
Improve detection for DES support in OpenSSL, to allow compilation
against system OpenSSL without DES.
Note that MariaDB needs to be compiled against OpenSSL-like library
that itself has DES support which cmake detected. Positive detection
is indicated with CMake variable HAVE_des 1.
Signed-off-by: Dimitri John Ledkov <dimitri.ledkov@surgut.co.uk>
`FindZLIB` module uses variable `ZLIB_ROOT`[1] to look for libraries. By
setting the variable, `FindZLIB` is able to search the libraries that
installed in a non-system path (/workspace/mylib for example).
And when using `z` in `LINK_LIBRARIES()` CMake tries to lookup the
library in system path by default. It doesn't work if the library isn't
installed in the path, and use ${ZLIB_LIBRARY} which set by FindZLIB
solve the issue.
All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the
BSD-new license. I am contributing on behalf of my employer Amazon Web
Services.
[1]: https://cmake.org/cmake/help/latest/module/FindZLIB.html#hints
The libpmem dependency that had been added in
commit 3daef523af (MDEV-17084)
did not achieve any measurable performance improvement when
comparing the same PMEM device with and without "mount -o dax"
using the Linux ext4 file system.
Because Red Hat has deprecated libpmem, let us remove the code
altogether.
Note: This is a 10.6 version of
commit 3f9f5ca48e
which will retain PMEM support in MariaDB Server 10.11.
Because the Red Hat Enterprise Linux 8 core repository does not include
libpmem, let us implement the necessary subset ourselves.
pmem_persist(): Implement for 64-bit x86, ARM, POWER, RISC-V, Loongarch
in a way that should be compatible with the https://github.com/pmem/pmdk/
implementation of pmem_persist().
The CMake option WITH_INNODB_PMEM can be used for enabling or disabling
this interface at compile time. By default, it is enabled on all applicable
systems that are covered by our CI system.
Note: libpmem had not been previously enabled for Loongarch in our
Debian packaging. It was enabled for RISC-V, but we will not enable it
by default on RISC-V or Loongarch because we lack CI coverage.
The generated code for x86_64 was reviewed and tested on two
Intel implementations: one that only supports clflush, and
another that supports both clflushopt and clwb.
The generated machine code was also reviewed on https://godbolt.org
using various compiler versions. Godbolt helpfully includes an option
to compile to binary code and display the encoding, which was
useful on POWER.
Reviewed by: Vladislav Vaintroub
