Hi All
We are tuning Impala 2.5 CDH5.71 on a large cluster. We got the following statistics that we are not able to figure out the reason why the average non-child time of ExchangeNode (id=55) is significatly different from the actual non-child time of each instance. Can anyone help to explain?
Averaged Fragment F18:(Total: 9m14s, non-child: 0.000ns, % non-child: 0.00%)
split sizes: min: 0, max: 0, avg: 0, stddev: 0
completion times: min:9m14s max:9m14s mean: 9m14s stddev:193.642ms
execution rates: min:0.00 /sec max:0.00 /sec mean:0.00 /sec stddev:0.00 /sec
num instances: 38
Line 657: EXCHANGE_NODE (id=55):(Total: 9m10s, non-child: 9m10s, % non-child: 100.00%)
Line 2109: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 721.501ms, % non-child: 0.13%)
Line 2263: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 757.946ms, % non-child: 0.14%)
Line 2430: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 735.455ms, % non-child: 0.13%)
Line 2597: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 719.390ms, % non-child: 0.13%)
Line 2764: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 739.788ms, % non-child: 0.13%)
Line 2931: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 746.737ms, % non-child: 0.14%)
Line 3098: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 785.411ms, % non-child: 0.14%)
Line 3265: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 729.887ms, % non-child: 0.13%)
Line 3432: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 760.815ms, % non-child: 0.14%)
Line 3599: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 706.177ms, % non-child: 0.13%)
Line 3766: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 761.745ms, % non-child: 0.14%)
Line 3933: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 712.175ms, % non-child: 0.13%)
Line 4100: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 708.088ms, % non-child: 0.13%)
Line 4267: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 756.727ms, % non-child: 0.14%)
Line 4434: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 705.065ms, % non-child: 0.13%)
Line 4601: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 763.063ms, % non-child: 0.14%)
Line 4768: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 728.033ms, % non-child: 0.13%)
Line 4935: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 717.250ms, % non-child: 0.13%)
Line 5102: EXCHANGE_NODE (id=55):(Total: 9m10s, non-child: 735.945ms, % non-child: 0.13%)
Line 5269: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 770.983ms, % non-child: 0.14%)
Line 5436: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 725.207ms, % non-child: 0.13%)
Line 5603: EXCHANGE_NODE (id=55):(Total: 9m10s, non-child: 767.848ms, % non-child: 0.14%)
Line 5770: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 741.356ms, % non-child: 0.13%)
Line 5937: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 766.130ms, % non-child: 0.14%)
Line 6104: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 680.675ms, % non-child: 0.12%)
Line 6271: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 772.464ms, % non-child: 0.14%)
Line 6438: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 776.331ms, % non-child: 0.14%)
Line 6605: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 689.149ms, % non-child: 0.13%)
Line 6772: EXCHANGE_NODE (id=55):(Total: 8m59s, non-child: 714.814ms, % non-child: 0.13%)
Line 6939: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 733.797ms, % non-child: 0.13%)
Line 7106: EXCHANGE_NODE (id=55):(Total: 9m10s, non-child: 732.212ms, % non-child: 0.13%)
Line 7273: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 723.093ms, % non-child: 0.13%)
Line 7440: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 780.243ms, % non-child: 0.14%)
Line 7607: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 721.486ms, % non-child: 0.13%)
Line 7774: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 752.089ms, % non-child: 0.14%)
Line 7941: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 713.284ms, % non-child: 0.13%)
Line 8108: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 727.432ms, % non-child: 0.13%)
Line 8275: EXCHANGE_NODE (id=55):(Total: 9m11s, non-child: 772.459ms, % non-child: 0.14%)
