最重要一点：

TorMysql的增删改查都会起一个事务，所以即使是查询，也需要最后显式commit；之前在使用的时候就没注意，导致mysql积压了一堆操作，看起来的现象是各种对mysql的操作都延时了。

import tormysqlimport pymysql.cursorsfrom tornado import genpool = tormysql.ConnectionPool(    max_connections=500,  # max open connections    idle_seconds=7500,  # connection idle timeout time, 0 is not timeout    wait_connection_timeout=600,  # wait connection timeout    host="x.x.x.x",    user="xxxx",    passwd="passxxx",    db="test_db",    charset="utf8",    cursorclass=pymysql.cursors.DictCursor  # 获取的是字典形式， 没有这句获取的是元组)class Mysql:    def __init__(self, table):        self.table = table    @gen.coroutine    def fetch(self, select_items, where_items):        table = self.table        with (yield pool.Connection()) as conn:            try:                with conn.cursor() as cursor:                    data_count = yield cursor.execute(f"SELECT {select_items} FROM {table} where 1 {where_items}")                    resp = cursor.fetchall()            except:                raise gen.Return(None)            else:                yield conn.commit()                raise gen.Return(resp)    @gen.coroutine    def put(self, new_val_map, where_items):        table = self.table        with (yield pool.Connection()) as conn:            try:                with conn.cursor() as cursor:                    data_count = yield cursor.execute(f"UPDATE {table} SET {new_val_map} where 1 {where_items}")            except:                yield conn.rollback()                raise gen.Return(False)            else:                yield conn.commit()                raise gen.Return(True)    @gen.coroutine    def post(self, fileds, new_val):        table = self.table        with (yield pool.Connection()) as conn:            try:                with conn.cursor() as cursor:                    data_count = yield cursor.execute(f"INSERT INTO {table} {fileds} VALUES {new_val}")                    new_id = cursor.lastrowid            except:                yield conn.rollback()                raise gen.Return(False)            else:                yield conn.commit()                raise gen.Return(True)