- Added a thread that fetches commit_count for open tables. This
will mean that NDB will not have to be contacted for every use of a cached query.
sql/ha_ndbcluster.cc:
Added a thread that periodically will fetch commit_count
for open tables and store that value in share.
The commit count value is then used when query cache
asks if a cached query can be used.
The thread activation interval is regulated by the
config variable ndb_cache_check_time, it's default value is 0
which means that NDB is contacted every time a cached query is reused.
sql/ha_ndbcluster.h:
Added commit_count to share
Added ndb_cache_check_time
sql/mysqld.cc:
Added config variable ndb_cache_check_time
sql/set_var.cc:
Added config variable ndb_cache_check_time
