Why my linux sys% very high?

I'm running linux system on a arm box. It has 6 cpu cores. And I run some docker in the box. These docker process almost some IO tasks. Then I found that, the system load very high. such as:

Mem: 3818172K used, 21296K free, 96096K shrd, 29588K buff, 775740K cached
CPU: 34% usr 36% sys 0% nic 19% idle 0% io 0% irq 9% sirq
Load average: 23.11 25.30 25.44 36/1555 22148
PID PPID USER STAT VSZ %VSZ %CPU COMMAND
1652 2 root SW< 0 0% 10% [kswapd0]
21715 24420 root S 766m 20% 7% ./pcd
682 731 root S 1997m 53% 6% ./sto
21578 23882 root S 765m 20% 4% ./pcd
12119 12065 root S 85092 2% 4% {APP} /usr/local/galaxy/plugin
21646 24198 root R 766m 20% 4% ./pcd
11616 11559 root S 85312 2% 3% {APP} /usr/local/galaxy/plugin
10235 10176 root S 85392 2% 3% {APP} /usr/local/galaxy/plugin
10914 10840 root S 84592 2% 3% {APP} /usr/local/galaxy/plugin
11245 11175 root S 86424 2% 3% {APP} /usr/local/galaxy/plugin
17378 16739 root S 297m 8% 2% happ:

And through the iostat cmd ,I confirm the RAM is enoughSo my question is : whether the running task too many so lead the sys% very high? If so, how to confirm.