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

learn more… | top users | synonyms

4
votes
3answers
234 views

How to view a specific process in top

Are there any relatively strightforward options with top to track a specific process? Ideally by identifying the process by a human readable value? e.g. chrome or java. In other words, I want to view ...
4
votes
1answer
245 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
votes
1answer
78 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
328 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
2answers
334 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
2answers
5k views

ATOP shows red line vmcom and vmlim. What does it mean?

utility atop shows: ATOP - MyServer 2013/01/07 00:03:57 10 seconds elapsed PRC | sys 2.18s | user 8.33s | #proc 141 | #zombie 0 | #exit 0 | CPU | sys 21% | ...
3
votes
3answers
10k 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
4answers
14k views

Change top's sorting back to CPU

A former coworker did something to top that whenever it runs as root the data is sorted by MEM usage instead of the default CPU usage. According to multiple searches, the man page and even the options ...
3
votes
3answers
6k 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 ...
3
votes
3answers
7k 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. ...
3
votes
2answers
210 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
1answer
5k 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
625 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
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 ...
3
votes
1answer
5k 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 ...
3
votes
2answers
662 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
491 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
520 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
405 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
601 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
2answers
54 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
411 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
votes
0answers
675 views

Why would whois take up 100% of the CPU?

Running top on my CentOS web server shows an instance of whois running from 99-100% of one of the CPUs. I've not knowingly used whois on this server before, would it be safe just to kill this ...
3
votes
0answers
197 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
219 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
296 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
749 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
810 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
3k 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
302 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

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
409 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 ...
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
164 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
498 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
35 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
1k 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
151 views

monitor multiple pids with top

I want to monitor memory usage for several processes and came up with a command like this: ps aux |grep -e postgres -e unicorn -e nginx|cut -d' ' -f2|for i in $(xargs); do echo $i; done 16112 16113 ...
2
votes
1answer
43 views

`top` not refreshing screen on exit

When I exit top, the prompt reappears at the bottom and I can see the bottom of the last thing it was showing. How can I get top to behave like less i.e. refresh the screen back to when I launched ...
2
votes
1answer
2k views

Total CPU usage and CPU usage under processes list is different in FreeBSD top implementation?

For some reason, overall CPU usage on my FreeBSD machine fluctuates between 1% and 85%, but the CPU usage in processes column never adds up to this amount. For example here the overall CPU usage is ...
2
votes
1answer
637 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 ...
2
votes
1answer
8k 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 ...
2
votes
1answer
116 views

What does a high load with an empty top mean? [duplicate]

What does it mean when I have a non-trivial load and when I run top, there are no processes using non-trivial amounts of cpu time? For example, I have a server with this top line: top - 10:10:59 up ...
2
votes
0answers
30 views

Restrict a user from viewing other user's processes [duplicate]

Suppose there are two users : user1 & user2. Now we know that if I give top -u user1, I can see only the process respective to user1. But if I do top -u user2, I can see all the process running ...
2
votes
0answers
32 views

Identify process

Every couple of minutes my Mac OSX machine starts running a process that consumes 10% of the CPU. It runs for a couple of seconds and then stops. I can see the process coming up in 'Top', but the name ...
2
votes
1answer
70 views

Where does network waiting go in 'top'?

If top is showing high loads, and you don't know if the process causing it is doing processor time or is doing network i/o (not local i/o) how can you find that out? On our server I see high values ...
2
votes
1answer
66 views

Unrealistically long process times displayed in top

I (partly) manage a small cluster and we are having some problems on a few nodes (running CentOS 6.4). Some processes show exceptionally long run-times in 'top', even though the computer has been ...