on Windows".
On platforms where read-write lock implementation does not
prefer readers by default (Windows, Solaris) server might
have deadlocked while detecting MDL deadlock.
MDL deadlock detector relies on the fact that read-write
locks which are used in its implementation prefer readers
(see new comment for MDL_lock::m_rwlock for details).
So far MDL code assumed that default implementation of
read/write locks for the system has this property.
Indeed, this turned out ot be wrong, for example, for
Windows or Solaris. Thus MDL deadlock detector might have
deadlocked on these systems.
This fix simply adds portable implementation of read/write
lock which prefer readers and changes MDL code to use this
new type of synchronization primitive.
No test case is added as existing rqg_mdl_stability test can
serve as one.
using cmake option INSTALL_LAYOUT=STANDALONE would produce the layout as in
tar.gz or zip packages.
INSTALL_LAYOUT=UNIX will produce unixish install layout (with mysqld being in sbin subdirectory , libs in lib/mysql etc). This layout is used for RPM packages.
Subtle differences in both packages unfortunately lead to the need to recompile MySQL to use with other package type - as otherwise for example default plugins or data directories would be wrong set.
There are numerous other variables that allow fine-tuning packaging layout. (INSTALL_BINDIR, INSTALL_LIBDIR , INSTALL_PLUGINDIR etc).
This options are different from autotools as they do not expect full paths to directories, but only subdirectory of CMAKE_INSTALL_PREFIX.
There are 2 special options that expect full directory paths
- MYSQL_DATADIR that defines default MYSQL data directory (autotools equivalent
is --localstatedir)
- SYSCONFDIR can be added to search my.cnf search path (autotools equivalent is --sysconfdir)