A command-line system monitor tool that produces a frequently-updated list of processes.

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5
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2answers
2k views

iotop but for particular disk?

Is there a tool like iotop but for monitoring IO on specific volumes? (Or perhaps I missed a way to filter iotop?) If not is there any way to get at this information via (say)/proc? (dstat etc. ...
4
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3answers
7k views

Why is apache2 showing up a defunct in the process list?

When I run top I see one line that doesn't look too good: 2475 www-data 20 0 0 0 0 Z 1 0.0 0:00.19 apache2 <defunct> Why is this process <defunct> and what should I ...
4
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1answer
156 views

grep of top output yields funny characters upon redirection to file

I am running CentOS 6 and I am trying to grep the output of top and redirect it to a file. I.e. top -u user1 -n 1 | /bin/grep somecommand &> scratch.txt The output of vim scratch.txt is ...
4
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3answers
8k views

Killing a tree of processes in top/htop

htop allows me to nicely see trees of processes within the shell. I can kill processes by pressing F9 (KILL) and then selecting which signal (e.g. 15 SIGTERM) I want to send to a job to kill. ...
4
votes
1answer
7k views

CPU and core usage stats

I'm running some programs on a server and I would like to know how much % cpu I'm taking up and how many cores are being utilised by my process. To clarify, the server has 16 CPUs, all quad-core. I ...
4
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2answers
1k views

How can we use the command 'top‘ to monitor the total CPU usage and each processor usage simultaneously?

You know that we can use the command top to monitor the real-time CPU usage and toggle the result display to the per-processor view by pressing key 1. The disadvantage of it is you can only monitor ...
4
votes
1answer
197 views

How can I turn off the realtime display of unix command “top”?

I want top to just give me the results when I call it and then exit. How can this be done? top's manpage does not list any flag for this purpose. Also, I do not want to use ps -eLf for the purpose.
4
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2answers
121 views

top: how to cancel current command?

While browsing processes on a shared server in top I accidentally hit the r key which prompted me with renice. I had no clue what this was going to do with my input and found no way to go back. I ...
4
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2answers
3k views

What is the STATE column of the TOP command on Solaris?

I'm running a very large, memory intensive program on my new UNIX server and trying to fully understand the output of the "top" command. Here is what I see right now (showing only the first process): ...
4
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2answers
1k views

How can i redirect the output to a file when the program is build with ncurses library [duplicate]

Possible Duplicate: Removing control chars (including console codes / colours) from script output If we redirect output to file in this pattern top >> somefile.txt, we get lot of ...
4
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1answer
305 views

show hostname in top

I'm using top with tmux to monitor the most-CPU-consuming processes on different computers. How can I get the hostname to be displayed in each pane? Can I tell top to display the hostname somehow?
4
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1answer
189 views

CPU usage of file system operations not shown in top

I run the following command (which does ls for 10,000 times) in a Ubuntu Linux terminal and use the top command to monitor the CPU usage. While top shows the total CPU usage (line 2) is about 48% ...
4
votes
1answer
492 views

how to list all instances of an application?

How do I list all instances of an application. ie I am running 12 instances of application called "tcpA" I would like to list all of them. Below is top, I don't know if there is a way to look at a ...
4
votes
1answer
2k views

How to interpret busybox “top” output?

I am using BusyBox on a small embedded ARM system. I'm trying to read the "top" output, in particular for the Python process listed. How much real memory is this process using? Also what does VSZ ...
4
votes
2answers
534 views

CPU percentage of a single process

How do I get the average CPU percentage (for every second) consumed by a single process since it starts until it ends (exists)? Could I make this with Top?
4
votes
1answer
58 views

The sum of % in the CPU column doesn't match the total CPU % row [duplicate]

I don't understand why the sum of % in the cpu column in top doesn't match the total CPU % row: Text version with slightly different values: ubuntu@server:~$ top top - 23:20:21 up 5:18, 3 users, ...
3
votes
3answers
13k views

What is the difference between ps and top command?

What is the difference between ps and top command ? I see that both can display information about running processes . Which one should be used when ?
3
votes
1answer
6k views

htop reporting much higher memory usage than free or top

The following three outputs were taken essentially simultaneously: top: top - 02:54:36 up 2 days, 13:50, 3 users, load average: 0.05, 0.05, 0.09 Tasks: 181 total, 1 running, 179 sleeping, 0 ...
3
votes
2answers
219 views

Shouldn't there be more RAM free than this? [duplicate]

Possible Duplicate: Correctly determining memory usage in Linux I see that almost all my RAM is in use. Is this bad? Strange thing is I don't see what is actually using the RAM.
3
votes
2answers
685 views

Memory management, bias to swapping

I was having 768 MB RAM. In a general day MySQL was using 100-180 mb of RAM and MySQL was swapping 80-120 mb. I was having 50-60 mb free RAM. So I thought I should upgrade. Then I upgraded my RAM ...
3
votes
2answers
587 views

Setting the TOPCOLORS environment variable

I don't seem to be able to find any examples on the Internet for this environment variable, which top will apparently read and use to display colours. How would I set this variable correctly so top ...
3
votes
2answers
730 views

How is FireFox running on a virtual machine that has no display?

I am using a Red Hat virtual machine, accessible only remotely. However when I use the top command, one of the displayed processes taking up the most memory is firefox, located at ...
3
votes
2answers
912 views

PBS equivalent of 'top' command: avoid running 'qstat' repeatedly

When I run several jobs on a head node, I like to monitor the progress using the command top. However, when I'm using PBS to run several jobs on a cluster, top will of course not show these jobs, and ...
3
votes
3answers
573 views

How can I keep track of what's using the most CPU?

I use nagios to monitor my server. Once in a while I'll get a report that the CPU load is warning / critical, etc. Usually this happens at some odd hour or when I don't have the tools to immediately ...
3
votes
2answers
2k views

How to troubleshoot high load, when there are no obvious processes [duplicate]

I'm running Ubuntu 13.10 on a laptop. Recently, after waking from sleep, I noticed the computer was quite warm, checked top and discovered 1.00 load average. I shutdown Chrome, various daemons, no ...
3
votes
1answer
48 views

program executing for 2 days

I have a java program which implements the Hungarian algorithm. I made changes to the existing code in such a way that the input is read from file. I have a pretty huge input around 32,000 rows for ...
3
votes
1answer
926 views

output of top gets truncated to 80 columns when run by cron

I have got the following logging script: #!/bin/bash top -b -c -n 1 >> /var/log/toplog/top.log And the following record in my crontab: */1 * * * * /home/clime/scripts/toplog.sh The ...
3
votes
2answers
1k views

How can I kill the top CPU/IO process quickly?

I find that sometimes my Linux will stop responding, so I need to switch to another terminal with CtrlAltF2, and type a command to kill the top CPU usage process or top IO usage process, so that the ...
3
votes
1answer
19k views

How to check which process is using most memory

When I check free in one of Prod server it showing 70% of memory is being used: total used free shared buffers cached Mem: 164923172 141171860 23751312 ...
3
votes
2answers
183 views

How can I tell which process is IO bound?

Suppose I have a large number of processes and one (or more) is IO bound, obvious by a high wa value in top. How can I pinpoint which process it is? Each process shows how much cpu is being used, but ...
3
votes
1answer
432 views

HP-UX SZ limit for ps?

Right so I have a fun little thing that I'm deathly confuzzled about. I have a program that is running and I am getting the following: using top: SIZE RES 1639M 359M using ps: SZ 20171 ...
3
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0answers
61 views

Memory consumption over variable period of time

There are a number of questions on this StackExchange about memory consumption, notably: How to check which process is using most memory How to display top results sorted by memory usage in real ...
3
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0answers
236 views

What is the difference between the output of TOP command and Oprofile?

In the top command one of the processes is always showing a CPU usage of 4 to 5%. But in oprofile the CPU usage is 0.004%. I do not understand this. And I also noticed that even when a process is in ...
3
votes
4answers
253 views

What is using memory? [closed]

According to htop and free, the machine I'm looking at is currently at 6631 / 11907 MB of RAM. That's more or less half of the RAM available. However when I sort top or htop by MEM%, the most memory ...
2
votes
2answers
834 views

Why linux uses swap memory when there are still tons of physical memory unused

root@host [/home4/nudenude/public_html/hello/cache]# top -r top: unknown argument 'r' usage: top -hv | -abcHimMsS -d delay -n iterations [-u user | -U user] -p pid [,pid ...] root@host ...
2
votes
2answers
343 views

Tool for viewing top N items in stream

I'm looking for an existing Linux command-line tools that can accomplish the following: Consider there is an input stream /dev/inputstream which spews an infinite stream of data that looks like this: ...
2
votes
2answers
1k views

Is there a way to get “top” to run exactly once and exit?

I find the output of the shell command top to be a simple and familiar way to get a rough idea of the health of a machine. I'd like to serve top's output (or something very similar to it) from a tiny ...
2
votes
3answers
4k views

How to show CPU time for processes via top without 'root' procs

Okay, So I've been attempting this for about three hours now without success. How do you search/display/use the top command (or ps command if it works...) to output a list of all procs, sorted by CPU ...
2
votes
2answers
3k views

What does “batch mode” mean for the top command?

I was reading about the top command and I came across something I don't quite understand: top options: -b Run in batch mode. This is useful for sending output from top to other programs or to ...
2
votes
2answers
395 views

How does a parallelized Python program look with top command?

I work on a shared cluster. I've seen people run parallelized c code on this cluster which, when I use top to see what processes are running, are shown to be using (for example) 400% of the CPU, ...
2
votes
2answers
2k views

Find the PID of top CPU/MEM usage, save to a shell variable

Is there any way to get the PID of the top CPU/MEM usage, I need to use that in a script, top command doesn't seem to work for it.
2
votes
1answer
2k views

How do I get the old procps-ng top(1) layout back (pre-3.3.10)?

Since updating to procps-ng 3.3.10 my top(1) looks like this: Instead of: Not only are these colours annoying & offensive, I can't get it to sort as the "old" top(1) (O no longer works, and ...
2
votes
1answer
3k views

Why highest priority threads are displayed with RT in top and htop?

In the top and htop tools, processes (or/and threads depending on display settings) having the highest realtime priority (99 from the userland API point of view) with either the scheduling policy ...
2
votes
2answers
2k views

How to interpret this top command

top - 04:36:16 up 32 days, 2:33, 1 user, load average: 251.72, 250.54, 231.19 Tasks: 785 total, 249 running, 522 sleeping, 2 stopped, 12 zombie Cpu(s): 8.9%us, 90.5%sy, 0.4%ni, 0.0%id, ...
2
votes
4answers
170 views

How to find out what is this process for?

I have this 'java' process running for 3 hours ( I guess ). I didn't see it before and I wonder how could I find out where it's coming from? Here is a screenshot: EDIT: ok I figured it out, it's ...
2
votes
1answer
540 views

Where does top / gnome-system-monitor get its information about cpu usage?

I am curious where gnome-system-monitor and top (the command line tool) get their information about the CPU usage in %. Could you please explain it to me?
2
votes
1answer
54 views

How to interpreted top/htop memory usage

I have a htpc/server-ish ubuntu box running at home with kodi (xbmc) and some other webservices. I noticed kodi was laggish and ssh'ed into the box to see what was going on. I saw this htop output: ...
2
votes
1answer
82 views

Set default color for top

How do you set the default color for top? Right now there is a red that I can barely read. You can toggle from mono to color with z or set it up more thoroughly with Z. But none of those settings ...
2
votes
1answer
867 views

Make top shows only server process

Can I make top show info about the web and db servers? Can it be done by piping the pids to the top? They can be many process from every one?!? Or is there any better method for this?
2
votes
1answer
39 views

Display only certain parameters in top

I have a question pertaining the 'top' command and dissecting it. What I mean by that is say for instance I wanted to display only particular parameters while top is running live, I want to only ...