Why planning_time cost so long?


#1

EXPLAIN ANALYZE

.
└── select
├── execution_time: 93.357518ms
├── planning_time: 294.164469ms
├── total_time: 387.521987ms
└── auxiliary_iterators
├── labels
│ └── statement: SELECT appName::tag, idle::float, iowait::float, nodegroup::tag, real_hostname::tag, real_ip::tag, site::tag, steal::float, system::float, unit::tag, “user”::float FROM failover_basic_metrics.failover_basic_metrics_rp.cpu WHERE appName::tag = ‘xxx’
└── create_iterator
├── labels
│ ├── cond: appName::tag = ‘xxx’
│ ├── measurement: cpu
│ └── shard_id: 6
├── cursors_ref: 0
├── cursors_aux: 22910
├── cursors_cond: 0
├── float_blocks_decoded: 22830
├── float_blocks_size_bytes: 178497652
├── integer_blocks_decoded: 0
├── integer_blocks_size_bytes: 0
├── unsigned_blocks_decoded: 0
├── unsigned_blocks_size_bytes: 0
├── string_blocks_decoded: 0
├── string_blocks_size_bytes: 0
├── boolean_blocks_decoded: 0
├── boolean_blocks_size_bytes: 0
└── planning_time: 293.90274ms