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

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100.0%sy with poor disk performance

I have RHEL 5.4 kernel 2.6.18-164.el5 and I am experiencing very bad disk performance that happens randomly during working with Oracle. Nothing appears in the logs. When it happens, I see one CPU ...
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3k 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 ...
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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 process?...
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491 views

High %sy in top output, how to debug?

We have 2 identically configured servers and one of them is showing a high %sy while the other does not. This would seem to indicate that the system is busy doing something. Cpu(s): 28.1%us, 66.3%sy,...
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321 views

How to monitor top applications using CPU (and IO if possible) in a graph?

I need to find what and when these applications used so much CPU (and IO if possible too). This should be in a graphic timeline like we see in GNOME System Monitor CPU History. I also want to compare ...
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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 ?
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Differences and relations between VIRT and USED in output of top?

From manpage of top VIRT -- Virtual Memory Size (KiB) The total amount of virtual memory used by the task. It includes all code, data and shared libraries plus pages that ...
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179 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 ^...
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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. However,...
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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 ...
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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 garbage ...
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8k 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 ...
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198 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.
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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 ...
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4k 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): ...
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1k 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 ...
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363 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?
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294 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% (13....
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658 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 ...
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652 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?
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1answer
147 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, ...
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819 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 ...
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1answer
7k 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 ...
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226 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.
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698 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 ...
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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 ...
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784 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 /usr/lib64/firefox-3....
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3answers
596 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 ...
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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 ...
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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 ...
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364 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 ...
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448 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 ...
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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 ...
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33 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 ...
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1answer
432 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 ...
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273 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 ...
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289 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 ...
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907 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 [/...
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389 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: ...
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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
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1answer
155 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 ...
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1answer
4k 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 ...
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1answer
19k views

Huge CPU load due to high system usage

Tasks: 747 total, 176 running, 560 sleeping, 0 stopped, 11 zombie Cpu(s): 10.5%us, 89.2%sy, 0.0%ni, 0.0%id, 0.0%wa, 0.0%hi, 0.3%si, 0.0%st Mem: 74236420k total, 73285344k used, 951076k ...
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2answers
5k 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 ...
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489 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, ...
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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.
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32 views

Process Scheduling Information Extraction

I want to extract the process having highest utilization on each processor core and then output its information (PID etc.) to a file. How can I do it by using either top or ps command? Thanks.
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1answer
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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 ...
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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, 0.0%...
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4answers
174 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 ...