Also fix perfschema.hostcache_ipv6_max_con.
The test case makes use of a debug switch to execute some special code.
The code does hostname replacement. Every hostname sent during connect
phase becomes santa.claus.ipv4.example.com (or ipv6). This causes a
connection from root@localhost to fail, as root is not registered as
santa claus user. The failure is only apparent on Windows as Unix
systems make use of sockets, which bypass the name resolution check
entirely.
MDEV--15609 engines/funcs.crash_manytables_number crashes with error 24
(too many open files)
MDEV-10286 Adjustment of table_open_cache according to system limits
does not work when open-files-limit option is provided
Fixed by adjusting tc_size downwards if there is not enough file
descriptors to use.
Other changes:
- Ensure that there is 30 (was 10) extra file descriptors for other usage
- Decrease TABLE_OPEN_CACHE_MIN to 200 as it's better to have a smaller
table cache than getting error 24
- Increase minimum of max_connections and table_open_cache from 1 to 10
as 1 is not usable for any real application, only for testing.