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impala query kudu table very slow

New Contributor

After a period of time in the kudu cluster, all queries have become slow. The following is the Impala query profile file, please help analyze it, thank you.

profile file


Cloudera Employee

The exchange operators seem to be the bottleneck:

16:EXCHANGE 1 26m14s 26m14s 22.55K 0 0 0 KUDU(KuduPartition(shift_timekey)) 
13:EXCHANGE 1 26m13s 26m13s 21.46K -1 0 0 HASH(t.pnl_id,d.oper_code,d.factory)
12:EXCHANGE 1 24m17s 24m17s 108.37M -1 0 0 BROADCAST

Each take 20+ minutes.

More importantly, the profile says "WARNING: The following tables are missing relevant table and/or column statistics. rptpid.i_f_r_mes_hist_pnl_mod, rptpid.i_f_t_mes_hist_gop_inout_fab". You should compute stats on these tables. Having accurate statistics is important for Impala performance.