有的时候同样的sql查询很快，详细信息
Projection_4, 5510288.92, 0, root, , time:506.7ms, loops:1, Concurrency:8, stat.st_summary_bill_sync_confirm.i_summary_id, 8.72 KB, N/A
└─IndexLookUp_7, 5510288.92, 0, root, , time:506.6ms, loops:1, table_task: {total_time: 4.02s, num: 0, concurrency: 8}, , 1.14 KB, N/A
├─IndexRangeScan_5(Build), 5510288.92, 0, cop[tikv], table:st_summary_bill_sync_confirm, index:IDX_SYNC_STATUS(I_SYNC_STATUS), time:502.9ms, loops:1, cop_task: {num: 1478, max: 466.1ms, min: 172.3µs, avg: 648.4µs, p95: 400.6µs, tot_proc: 513ms, tot_wait: 56ms, rpc_num: 1478, rpc_time: 947.1ms, copr_cache_hit_ratio: 1.00}, tikv_task:{proc max:465ms, min:44ms, p80:139ms, p95:189ms, iters:1478, tasks:1478}, scan_detail: {total_process_keys: 0, total_keys: 1567009, rocksdb: {delete_skipped_count: 251214, key_skipped_count: 2886335, block: {cache_hit_count: 1640, read_count: 0, read_byte: 0 Bytes}}}, range:[0,0], keep order:false, N/A, N/A
└─TableRowIDScan_6(Probe), 5510288.92, 0, cop[tikv], table:st_summary_bill_sync_confirm, , keep order:false, N/A, N/A