What exactly load mean and how to measure

What exactly load mean and how to measure

In this scenario i have one machine with CPU(s): 4 which you can see below by lscpu command check the load before applying  any load on any server i am trying to apply load on my machine by starting application which consumes more memory ex:(vmware)any application which is running on your machine
mohammedrafi@NOC-RAFI:~$ date
Thu Sep 1 05:53:44 IST 2016

mohammedrafi@NOC-RAFI:~$ uptime
05:53:09 up 1 day, 6:27, 3 users, load average: 0.68, 0.69, 0.92

mohammedrafi@NOC-RAFI:~$ lscpu
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
CPU(s): 4
On-line CPU(s) list: 0-3
Thread(s) per core: 2
Core(s) per socket: 2
Socket(s): 1
NUMA node(s): 1
Vendor ID: GenuineIntel
CPU family: 6
Model: 42
Stepping: 7
CPU MHz: 800.000
BogoMIPS: 4988.45
Virtualization: VT-x
L1d cache: 32K
L1i cache: 32K
L2 cache: 256K
L3 cache: 3072K
NUMA node0 CPU(s): 0-3

 

I have started my application to work at the instance i started machine was very slow y ? u will understand once see output which i measured regularly and some description which i mentioned below.

mohammedrafi@NOC-RAFI:~$ uptime
05:57:08 up 1 day, 6:31, 3 users, load average: 5.78, 3.20, 1.84
mohammedrafi@NOC-RAFI:~$ uptime
05:59:27 up 1 day, 6:34, 3 users, load average: 4.46, 3.41, 2.10
mohammedrafi@NOC-RAFI:~$ uptime
06:02:04 up 1 day, 6:36, 3 users, load average: 0.99, 2.55, 2.00

The first decimal represents the average CPU load over the past minute. The second decimal is the average load over a 5 minute period. The third and final number is the average load over a 15 minute period. Using these 3 measurements you can get a sense of whether a spike was a short term occurrence or if it’s a prolonged event. If the third number is too high, you’ve got a problem to deal with. But what is ‘too high’?

The decimal represents the amount of active tasks requesting CPU resources to perform an action. If you think of the number in terms of percentage utilization, 1.0 represents 100% of a single CPU core. Anything over 1.0 represents the amount of processes which are waiting in line to be executed. In this way, the Linux style of measurement is more informative than the Windows percentage style because it doesn’t just tell you a CPU is overloaded, it also tells you by how much and over what time period.

An important note is that this number scales along side CPU cores. If you have 4 CPUs for example, 4.0 is equal to 100% utilization across all cores. The standard rule of thumb is that 70% utilization is healthy. Once you’re consistently above 70%, you need to start planning for expansion or else optimize your software. That means 0.70 per CPU core.

Actually load should be with in  or <4.00 since it reached more than 5… my machine was hanged for a while but finally after few minutes its stable once resource are settled

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