Reverts apache/doris#42255
We have found that after closing the connection pool, there will be
class loading problems and connection release problems for some data
sources. We will remove this function first and re-add it after solving
and testing it completely.
pick (#41992)
We initially introduced jdbc connection pool to improve the connection
performance of jdbc catalog, but we always found that connection pool
would bring some unexpected errors, so we chose to add a catalog
property: `enable_connection_pool` to choose whether to enable the jdbc
connection pool of jdbc catalog, and the default false.However, the
created catalog will still open the connection pool when it is upgraded,
and only the newly created catalog will be false
And we conducted performance tests on this, the performance loss is
within the expected range.
- Enable connection pool: mysqlslap -uroot -h127.0.0.1 -P9030
--concurrency=1 --iterations=100 --query='SELECT * FROM mysql.test.test
limit 1;' --create-schema=mysql --delimiter=";" --verbose
Benchmark
Average number of seconds to run all queries: 0.008 seconds
Minimum number of seconds to run all queries: 0.004 seconds
Maximum number of seconds to run all queries: 0.133 seconds
Number of clients running queries: 1
Average number of queries per client: 1
- Disable connection pool: mysqlslap -uroot -h127.0.0.1 -P9030
--concurrency=1 --iterations=100 --query='SELECT * FROM
mysql_no_pool.test.test limit 1;' --create-schema=mysql --delimiter=";"
--verbose
Benchmark
Average number of seconds to run all queries: 0.054 seconds
Minimum number of seconds to run all queries: 0.047 seconds
Maximum number of seconds to run all queries: 0.184 seconds
Number of clients running queries: 1
Average number of queries per client: 1
