Top is a UNIX program that shows system usage in real time.

learn more… | top users | synonyms

18
votes
2answers
6k views

Linux: Is there something similar to “top” for I/O?

My disk often is utilized, but top (and htop, a custom replacement) show nothing suspicious. Is there a way to sort processes by I/O (more specific: disk) utilization? EDIT Found out using iotop ...
8
votes
3answers
7k views

Filtering top command output

I'm running a Mac and want to filter the output of the top command for a particular process such that only the PID, COMMAND and %CPU columns are displayed. After getting the PID of the process, I ...
6
votes
2answers
4k views

Understanding top command in unix

When I run top -c command on my UNIX box I get the output below: top - 03:09:34 up 5 days, 6:14, 1 user, load average: 0.00, 0.00, 0.00 Tasks: 175 total, 1 running, 174 sleeping, 0 stopped, ...
14
votes
1answer
16k views

Why is the “top” command showing a CPU usage of 799%?

I am running a process in a 4 core Ubuntu server. However, top command shows that the CPU usage is 799% all the time. How can this be possible? I know for multi core CPUs, more than 100% CPU usage ...
10
votes
2answers
3k views

Why does the memory usage in “top” not add up?

I have noticed that sometimes when I run top, the memory usage of each process in the process table does not seem to add up to the total. For example, in the dump below, top says that I am using 16 ...
0
votes
1answer
832 views

disparity between `top`'s given CPU % and process CPU usage total

I've noticed that there are sometimes (large) differences between the reported total CPU usage and a summation of the per-process CPU utilization given by apps like top and wmtop. As an example: I ...
0
votes
4answers
822 views

How can I free memory on linux

When I use top to see memory usage, I have 65gb ram but only 1.3gb of it free and remaining is shown as used. When I ran my program It gives memory insufficiency error. Although no other program is ...
15
votes
3answers
11k views

Why is the CPU usage reported by top in Linux over 100%?

I've seen the CPU usage go over 100%. How is this possible? Is it because I have four CPU cores, so 100% isn't really the max? Also, when a program does this, what else can I do in top besides using ...
8
votes
4answers
3k views

Zombie process using 100% CPU

A zombie process, which should not be using any resources (RAM and CPU), is hogging up an entire core on my 8-core 64-bit Ubuntu 11.10 Desktop installation. This is the output of ps -el|grep Z: F S ...
3
votes
3answers
6k views

Writing a CPU/RAM usage log over a period of time to file on CentOS

I'm looking for an application or line of code that would let me observe a process, save the info in a number of variables, then put the gathered info on a file. I've been trying with variations of ...
3
votes
2answers
1k views

Where does top command get all the data for CPU Utilization?

When I run the top command, the third line is; Cpu(s): 0.3%us, 0.3%sy, 0.0%ni, 99.2%id, 0.1%wa, 0.0%hi, 0.0%si, 0.1%st From where does top command get this data? Does it get from /proc?, if ...
3
votes
1answer
734 views

How to redirect values from top command to a file in Mac OSX

All, I want to extract values from top for plotting purposes. I'm currently using the following command top -l 0 -s 1 -pid 12345 -stats rsize | awk 'NR%13==0' When I run this , I get the ...