Hi guys:
Our team want to test the apache impala(ver: 2.10.0) by TPCH, when running
on 20 concurrent queries against 24 dell PowerEdge R730, We found the test
cause lots of system cpu for a very long time, and no query completed
successfully. I don't known what happens, who can give me some advice?
some information output by top command:
%Cpu0 : 1.6 us, 84.8 sy, 0.0 ni, 13.6 id, 0.0 wa, 0.0 hi, 0.0 si,
0.0 st
%Cpu1 : 0.4 us, 86.0 sy, 0.0 ni, 13.6 id, 0.0 wa, 0.0 hi, 0.0 si,
0.0 st
%Cpu2 : 0.6 us, 86.0 sy, 0.0 ni, 13.4 id, 0.0 wa, 0.0 hi, 0.0 si,
0.0 st
%Cpu3 : 0.0 us, 86.2 sy, 0.0 ni, 13.8 id, 0.0 wa, 0.0 hi, 0.0 si,
0.0 st
%Cpu4 : 0.6 us, 87.1 sy, 0.0 ni, 12.3 id, 0.0 wa, 0.0 hi, 0.0 si,
0.0 st
%Cpu5 : 1.0 us, 86.3 sy, 0.0 ni, 12.7 id, 0.0 wa, 0.0 hi, 0.0 si,
0.0 st
%Cpu6 : 0.4 us, 86.0 sy, 0.0 ni, 13.6 id, 0.0 wa, 0.0 hi, 0.0 si,
0.0 st
.....
use "perf top" to see what happens:
84.24% [kernel] [k] KSTK_ESP
7.26% [kernel] [k] cpu_startup_entry
5.56% [kernel] [k] vm_is_stack
0.20% [kernel] [k] number.isra.2
0.18% [kernel] [k] format_decode
........
