Source: LinuxFoundationX: LFS101x.2 Introduction to Linux
top
http://alfredoroca.github.io/server/system/monitoring/2015/09/15/Monitoring-linux-with-top/
w
uptime, load average and user processes
09:48:49 up 2:01, 4 users, load average: 0.33, 0.37, 0.37
USER TTY LOGIN@ IDLE JCPU PCPU WHAT
alfredo :0 07:49 ?xdm? 20:53 0.25s gdm-session-worker [pam/gdm-password]
alfredo pts/0 07:52 23:32 7.12s 6.89s /home/alfredo/.rvm/rubies/ruby-2.2.0/bin/ruby bin/rails s
alfredo pts/1 07:52 12:11 0.91s 0.70s spring server | shk | started 1 hour ago
alfredo pts/2 08:26 1.00s 0.44s 0.00s w
uptime
uptime and load average
09:49:46 up 2:02, 4 users, load average: 0.47, 0.41, 0.39
Interpreting Load Averages
The load average is displayed using three different sets of numbers, as shown in the following example:
The last piece of information is the average load of the system. Assuming our system is a single-CPU system, the 0.25 means that for the past minute, on average, the system has been 25% utilized. 0.12 in the next position means that over the past 5 minutes, on average, the system has been 12% utilized; and 0.15 in the final position means that over the past 15 minutes, on average, the system has been 15% utilized. If we saw a value of 1.00 in the second position, that would imply that the single-CPU system was 100% utilized, on average, over the past 5 minutes; this is good if we want to fully use a system. A value over 1.00 for a single-CPU system implies that the system was over-utilized: there were more processes needing CPU than CPU was available.
If we had more than one CPU, say a quad-CPU system, we would divide the load average numbers by the number of CPUs. In this case, for example, seeing a 1 minute load average of 4.00 implies that the system as a whole was 100% (4.00/4) utilized during the last minute.
Short term increases are usually not a problem. A high peak you see is likely a burst of activity, not a new level. For example, at start up, many processes start and then activity settles down. If a high peak is seen in the 5 and 15 minute load averages, it would may be cause for concern.
load average: 0.47, 0.41, 0.39
1min 5min 15min