Let us introduce the parameter innodb_read_only_compressed
that is ON by default, making any ROW_FORMAT=COMPRESSED tables
read-only.
I developed the ROW_FORMAT=COMPRESSED format based on
Heikki Tuuri's rough design between 2005 and 2008. It might
have been a good idea back then, but no proper benchmarks were
ever run to validate the design or the implementation.
The format has been more or less obsolete for years.
It limits innodb_page_size to 16384 bytes (the default),
and instant ALTER TABLE is not supported.
This is the first step towards deprecating and removing
write support for ROW_FORMAT=COMPRESSED tables.
* Note: breaking change; since this commit, a plugin that has
worked so far might get rejected due to plugin maturity
* mariabackup is not affected (allows all plugins)
* VERSION file defines SERVER_MATURITY, which defines the
corresponding numeric value as SERVER_MATURITY_LEVEL in
include/mysql_version.h
* The default value for 'plugin_maturity' is SERVER_MATURITY_LEVEL - 1
* Logs a warning if a plugin has maturity lower than
SERVER_MATURITY_LEVEL
* Tests suppress the plugin maturity warning
* Tests use --plugin-maturity=unknown by default so as not to fail
due to the stricter plugin maturity handling
