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

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12
votes
6answers
9k views

How to make a process invisible to other users?

How could you launch a process and make it invisible to the top command? The process is started by a normal user (not root), and should not be visible to other normal users.
6
votes
1answer
2k views

top output: cpu usage > 100%

Here is the top output which I gathered: I noticed that top is showing vlc's cpu usage is > 100%. Can anybody please justify me why it is showing like this, whether this is a bug in top ...
32
votes
5answers
39k views

How to monitor CPU/memory usage of a single process?

I would like to monitor one process's memory / cpu usage in real time. Similar to top but targeted at only one process, preferably with a history graph of some sort.
21
votes
2answers
6k views

Why does `htop` show more process than `ps`

In ps xf 26395 pts/78 Ss 0:00 \_ bash 27016 pts/78 Sl+ 0:04 | \_ unicorn_rails master -c config/unicorn.rb 27042 pts/78 Sl+ 0:00 | ...
21
votes
4answers
12k views

How to display meminfo in megabytes in top?

Sometimes it is not comfortable to see meminfo in kilobytes while you have several gigs of RAM. In Linux it looks like that: And here is how it looks in Mac OS X: Is there a way to display ...
11
votes
2answers
12k views

Top and ps not showing the same cpu result

This is linked to this question. When I run top I get the following result: pid 3038 is using 18% cpu, however when running the result is 5.5%. And this number does not appear to be changing ...
2
votes
1answer
3k 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 ...
2
votes
2answers
1k 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, ...
49
votes
1answer
60k views

In Linux “top” command what are us, sy, ni, id, wa, hi, si and st (for CPU usage)?

When I issue $ top in linux, I get a result similar to this (see here). One of the lines has CPU usage information represented like this: Cpu(s): 87.3%us, 1.2%sy, 0.0%ni, 27.6%id, 0.0%wa, ...
11
votes
3answers
4k views

How can I receive top-like CPU statistics from the shell?

I'm trying to get an accurate read of my used CPU (in percent) from top. This is the command I'm running for testing: top -n1 | awk '/Cpu\(s\):/ {print $2}' This returns: 10.7%us, Which is the ...
5
votes
2answers
810 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
votes
2answers
2k views

Top Command - How to reduce the displayed Columns

Can we get specific column in a top command, for eg I'm interested in only the memory utilization and CPU usage column. How do I reduce the displayed columns of the top command to only the above two ...
4
votes
1answer
3k views

Why does top report the incorrect CPU usage?

I have a machine with Intel(R) Xeon(R) CPU E5520 visible as 16 logical cores (8 with HT). If I run something to eat CPU time (single threaded) top correctly reports 100% CPU usage for the process but ...
9
votes
1answer
5k views

Why the value of VSIZE in top is different from the value of VSZ (Virtual set size) in ps?

I know VSZ in ps is for the total address space allocated for the app and is sometimes aliased as vsize (mentioned in man page of ps on linux), but what's the definition of VSIZE in top? This top ...
5
votes
1answer
615 views

How do I stream a top snapshot into a file

Is there any way to persist the snapshot of top at that given moment into a file? I tried top > top.out but the contents were nothing like top in STDOUT: ^[[H^[[2J^[(B^[[mtop - 16:09:49 up 18 ...
4
votes
2answers
2k views

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 ...
2
votes
1answer
4k views

How to display `top` results sorted by memory usage in real time?

How can I display the top results in my terminal in real time so that the list is sorted by memory usage?
2
votes
1answer
3k 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 ...
1
vote
2answers
78 views

How to use top with only showing CMD name

How do you use top with just showing the CMD name? I have used top with just showing the running process that I want; for example: $ top -p 19745 And if I want more than one PID, I would use: $ ...
1
vote
2answers
3k views

free / top difference. Does free show virtual memory?

free -m shows me the following in my system: total used free shared buffers cached Mem: 3954 3842 111 0 248 2585 -/+ ...
0
votes
3answers
5k 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 ?