Editing Load (computing) (section)

=== Interpretation ===
For single-CPU systems that are [[CPU bound]], one can think of load average as a measure of system utilization during the respective time period. For systems with multiple CPUs, one must divide the load by the number of processors in order to get a comparable measure.

For example, one can interpret a load average of "1.73 0.60 7.98" on a single-CPU system as:

* During the last minute, the system was overloaded by 73% on average (1.73 runnable processes, so that 0.73 processes had to wait for a turn for a single CPU system on average).
* During the last 5 minutes, the CPU was idling 40% of the time, on average.
* During the last 15 minutes, the system was overloaded 698% on average (7.98 runnable processes, so that 6.98 processes had to wait for a turn for a single CPU system on average).

This means that this system (CPU, disk, memory, etc.) could have handled all the work scheduled for the last minute if it were 1.73 times as fast.

In a system with four CPUs, a load average of 3.73 would indicate that there were, on average, 3.73 processes ready to run, and each one could be scheduled into a CPU.

On modern UNIX systems, the treatment of [[Thread (computing)|threading]] with respect to load averages varies. Some systems treat threads as processes for the purposes of load average calculation: each thread waiting to run will add 1 to the load. However, other systems, especially systems implementing so-called [[Thread (computing)#M:N (hybrid threading)|M:N threading]], use different strategies such as counting the process exactly once for the purpose of load (regardless of the number of threads), or counting only threads currently exposed by the user-thread scheduler to the kernel, which may depend on the level of concurrency set on the process. Linux appears to count each thread separately as adding 1 to the load.<ref>See http://serverfault.com/a/524818/27813</ref>