Understanding Load Average on Linux

The load average is the average system load on a Linux server for a defined period of time. In other words, it is the CPU demand of a server that includes sum of the running and the waiting threads.

1. What is considered a high load average in Linux?
2. What is a good load average?
3. What is the average load on Unix or Linux machines?
4. How do I find CPU load average in Linux?
5. Is 100 CPU usage bad?
6. How can I produce high CPU load on Linux?
7. What is a bad load average?
8. How is load calculated?
9. What is load in top command?
10. What is a good CPU load?
11. Where is defunct process in Linux?
12. WHAT IS modules in Linux?

What is considered a high load average in Linux?

In practice, many sysadmins will draw a line at 0.70: The "Need to Look into it" Rule of Thumb: 0.70 If your load average is staying above > 0.70, it's time to investigate before things get worse. The "Fix this now" Rule of Thumb: 1.00. If your load average stays above 1.00, find the problem and fix it now.

What is a good load average?

Reading load averages

Usually, it's fine if the load average is above 1.0 per core in the last minute mark, but elevated load in the five or fifteen-minute averages could indicate a problem.

What is the average load on Unix or Linux machines?

System load/CPU Load – is a measurement of CPU over or under-utilization in a Linux system; the number of processes which are being executed by the CPU or in waiting state. Load average – is the average system load calculated over a given period of time of 1, 5 and 15 minutes.

How do I find CPU load average in Linux?

1. How To Check CPU Usage from Linux Command Line. top Command to View Linux CPU Load. mpstat Command to Display CPU Activity. sar Command to Show CPU Utilization. iostat Command for Average Usage.
2. Other Options to Monitor CPU Performance. Nmon Monitoring Tool. Graphical Utility Option.

Is 100 CPU usage bad?

If the CPU usage is around 100%, this means that your computer is trying to do more work than it has the capacity for. This is usually OK, but it means that programs may slow down a little. Computers tend to use close to 100% of the CPU when they are doing computationally-intensive things like running games.

How can I produce high CPU load on Linux?

To create a 100% CPU load on your Linux PC, do the following.

1. Open your favorite terminal app. Mine is xfce4-terminal.
2. Identify how many cores and threads your CPU has. You can get detailed CPU info with the following command: cat /proc/cpuinfo. ...
3. Next, execute the following command as root: # yes > /dev/null &

What is a bad load average?

A load average higher than 1 refers to 1 core/thread. So a rule of thumb is that an average load equal to your cores/threads is OK, more will most likely lead to queued processes and slow down things. ... A load average of 21 on a host with 24 cores will have idle CPU, even with those processes running 100%.

How is load calculated?

Each process using or waiting for CPU (the ready queue or run queue) increments the load number by 1. ... Systems calculate the load average as the exponentially damped/weighted moving average of the load number. The three values of load average refer to the past one, five, and fifteen minutes of system operation.

What is load in top command?

The load average is the average system load on a Linux server for a defined period of time. ... Typically, the top or the uptime command will provide the load average of your server with output that looks like: These numbers are the averages of the system load over a period of one, five, and 15 minutes.

What is a good CPU load?

How Much CPU Usage is Normal? Normal CPU usage is 2-4% at idle, 10% to 30% when playing less demanding games, up to 70% for more demanding ones, and up to 100% for rendering work. When watching YouTube it should be around 5% up to 15% (total), depending on your CPU, browser and video quality.

Where is defunct process in Linux?

How to spot a Zombie Process. Zombie processes can be found easily with the ps command. Within the ps output there is a STAT column which will show the processes current status, a zombie process will have Z as the status. In addition to the STAT column zombies commonly have the words <defunct> in the CMD column as well ...

WHAT IS modules in Linux?

What are Linux modules? Kernel modules are chunks of code that are loaded and unloaded into the kernel as needed, thus extending the functionality of the kernel without requiring a reboot. In fact, unless users inquire about modules using commands like lsmod, they won't likely know that anything has changed.