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[MySQL] Fail to acquire new connection during the transaction
After started the transaction I can no longer acquire new connection, until the transaction was finished. Is this an intentional behaviour? Thanks!!
let conn_pool: AnyPool = task::block_on(async {
AnyPoolOptions::new()
.max_connections(10)
.connect_timeout(Duration::from_secs(3))
.connect(&db_url)
.await
.unwrap()
})
Fail Case
let mut transaction = task::block_on(async {
match conn_pool.begin().await {
Err(e) => panic!(e),
Ok(c) => c,
}
});
... Insert & Update Actions
// ERROR: failed to get connection
let mut conn = match self.connection.conn_pool.try_acquire() {
None => return Err("failed to get connection".into()),
Some(c) => c,
};
Successful Case
let mut transaction = task::block_on(async {
match conn_pool.begin().await {
Err(e) => panic!(e),
Ok(c) => c,
}
});
... Insert & Update Actions
task::block_on(async {
transaction.commit().await.unwrap();
});
// ERROR: failed to get connection
let mut conn = match self.connection.conn_pool.try_acquire() {
None => return Err("failed to get connection".into()),
Some(c) => c,
};
When you call connect it creates just 1 connection. When you begin a transaction - that acquires one connection from the pool it's not returned to the pool until transaction is committed. Therefore there is no more idle connections in the pool so try_acquire returns None.
If you want to create 10 connections, then specify min_connections in pool options.
If you want to wait for additional connection to be opened (or become idle), then use acquire instead of try_acquire.
EDIT: Just realized it's an old issue. Anyway could be useful for someone who searches through issues.
@billy1624 It would be great if you had these changes since we have these problems very often
