The meaning of the average load of all hosts in CDH

1. The three numbers in the average load in the CDH host list are shown in the figure below, which represent the load conditions of 1 minute, 5 minutes, and 15 minutes respectively.

Second, the average load of the system-basic explanation

The meaning of these 3 numbers: respectively represent the average number of processes in the system running process queue in the past 1 minute, 5 minutes, and 15 minutes。

In the Linux shell, there are many commands to see Load Average, for example:

root@bigdata:~# uptime
12:49:10 up 182 days, 16:54, 2 users, load average: 0.08, 0.04, 0.01
root@bigdata:~# w
12:49:18 up 182 days, 16:54, 2 users, load average: 0.11, 0.07, 0.01
root@bigdata:~# top
top - 12:50:28 up 182 days, 16:55, 2 users, load average: 0.02, 0.05, 0.00

There is also a most direct command to display the average load of the system

root@bigdata:~# cat /proc/loadavg
0.10 0.06 0.01 1/72 29632

In addition to the first 3 numbers indicating the average number of processes, the next 1 fraction, the denominator indicates the total number of system processes, and the numerator indicates the number of running processes; the last number indicates the ID of the most recently running process.

Third, the average load of the system-advanced explanation

1. It is safe for a single-core load to be below 0.7, and optimization is required if it exceeds 0.7.

2. Use the following command to get the number of CPU cores directly

• grep ‘model name’ /proc/cpuinfo | wc -l

3. It is generally better to look at 5 minutes and 15 minutes, that is, the last 2 numbers

in conclusion

Get the number of CPU cores N, observe the next two numbers, 用数字 / Nand if you get the value, 小于0.7you can worry-free。

Reference: http://www.slyar.com/blog/linux-load-average-three-numbers.html