针对以下两种情况，可以做哪些优化？
问题1：
同个sql（查询paimon表）并发查询50 ，plan time增加
Execution Summary:
- Parse SQL Time: 3ms
- Nereids Lock Table Time: 4ms
- Nereids Analysis Time: 4ms
- Nereids Rewrite Time: 110ms
- Nereids Optimize Time: 6ms
- Nereids Translate Time: 2ms
- Workload Group: normal
- Analysis Time: 5ms
- Plan Time: 11sec788ms
- JoinReorder Time: N/A
- CreateSingleNode Time: N/A
- QueryDistributed Time: N/A
- Init Scan Node Time: 386ms
- Finalize Scan Node Time: 1sec331ms
- Get Splits Time: 1sec331ms
- Get Partitions Time: N/A
- Get Partition Files Time: N/A
- Create Scan Range Time: -3693ms
- Get Partition Version Time: N/A
- Get Partition Version Count (hasData): N/A
- Get Partition Version Count: N/A
- Get Table Version Time: N/A
- Get Table Version Count: N/A
- Schedule Time: 92ms
- Fragment Assign Time: 1ms
- Fragment Serialize Time: 14ms
- Fragment RPC Phase1 Time: 72ms
- Fragment RPC Phase2 Time: 5ms
- Fragment Compressed Size: 1.45 MB
- Fragment RPC Count: 6
问题2：
单个sql（查paimon表）查询， 进行连续执行数次，会有一次查询耗时明显偏高，查看profile文件主要是Nereids Analysis Time 和 Nereids Lock Table Time 指标明显升高。
将paimon catalog配置的刷新周期"metadata_refresh_interval_sec" 调大，查询时间有所降低，存在问题是刷新周期时间调大后，查不到最新数据，延迟太高(数据更新，paimon snapshot文件也会有变化，而元数据包括了文件信息)。
Execution Summary:
- Parse SQL Time: 15ms
- Nereids Lock Table Time: 13sec944ms
- Nereids Analysis Time: 6sec703ms
- Nereids Rewrite Time: 54ms
- Nereids Optimize Time: 183ms
- Nereids Translate Time: 4ms
- Workload Group: normal
- Analysis Time: 20sec631ms
- Plan Time: 1sec845ms
- JoinReorder Time: N/A
- CreateSingleNode Time: N/A
- QueryDistributed Time: N/A
- Init Scan Node Time: 111ms
- Finalize Scan Node Time: 199ms
- Get Splits Time: 199ms
- Get Partitions Time: N/A
- Get Partition Files Time: N/A
- Create Scan Range Time: -199ms
- Get Partition Version Time: N/A
- Get Partition Version Count (hasData): N/A
- Get Partition Version Count: N/A
- Get Table Version Time: N/A
- Get Table Version Count: N/A
- Schedule Time: 110ms
