Each spider connection is identified with a connection key, which is
an encoding of the backend parameters.
The first byte of the key is by default 0, and in rare circumstances
it is changed to a different value: when semi_table_lock is set to 1;
and when using casual read. When this happens, often a new connection
is created with the new key. Neither case is useful: the description
of semi_table_lock has nothing to do with creation of new connections
and the parameter itself was deprecated for 10.7+ (MDEV-28829) and
marked for deletion (MDEV-28830); while new threads created by
non-zero spider_casual_read causes only threads to be idle, thus not
achieving any gain, see MDEV-26151, and the param has also been
deprecated in 11.5+ (MDEV-31789). The relevant code adds unnecessary
complexity to the spider code. This change does not reduce
parallelism, because already when bgs mode is on a background thread
is created per partition, and there is no evidence spider creates
multiple threads for one partition. If the needs of such cases arise
it will be a separate issue.
The conn_kind, which stands for "connection kind", is no longer useful
because the HandlerSocket support is deleted and Spider now has only
one connection kind, SPIDER_CONN_KIND_MYSQL. Remove conn_kind and
related code.
Signed-off-by: Yuchen Pei <yuchen.pei@mariadb.com>
Reviewed-by: Nayuta Yanagisawa <nayuta.yanagisawa@mariadb.com>
Partial commit of the greater MDEV-34348 scope.
MDEV-34348: MariaDB is violating clang-16 -Wcast-function-type-strict
Change the type of my_hash_get_key to:
1) Return const
2) Change the context parameter to be const void*
Also fix casting in hash adjacent areas.
Reviewed By:
============
Marko Mäkelä <marko.makela@mariadb.com>
Partial commit of the greater MDEV-34348 scope.
MDEV-34348: MariaDB is violating clang-16 -Wcast-function-type-strict
The functions queue_compare, qsort2_cmp, and qsort_cmp2
all had similar interfaces, and were used interchangable
and unsafely cast to one another.
This patch consolidates the functions all into the
qsort_cmp2 interface.
Reviewed By:
============
Marko Mäkelä <marko.makela@mariadb.com>
We expand the tgt_odbc_str fields in SPIDER_SHARE for ha support, and
add the corresponding field in spider_direct_sql.
We also update the messages in monitoring, as odbc SERVER will cause
the usual connection fields (specifically, the one for database) not
to be populated with corresponding SERVER fields.
Remove the dead-code, in Spider, which is related to the Spider's
Oracle OCI support. The code has been disabled for a long time and
it is unlikely that the code will be enabled.
- document tmp_share, which are temporary spider shares with only one
link (no ha)
- simplify spider_get_sys_tables_connect_info() where link_idx is
always 0
