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Using a Toshiba Satellite l645d s4025 amd dual core p320 2.1ghz 3gb ddr3 ram 250 gb hdd

Below is the incomplete top report(don't know how to select all to copy) Using an Ubuntu 12.04 amd64 install/live dvd

Recently uninstalled Ubuntu 12.04 due to the fact that the processes(which in most cases there were 4-5 of each process running) were all using close to the same virtual memory listed above. (Possible fork bomb...I was ignorant enough to trust instructions that a later read I shouldn't have(wget http) don't remember the whole string.

I had no issues with performance due to the fact that the processes weren't using much physical ram and were not using any swap. As of now I reformatted the Hdd and have not assigned swap for my Live session.

Is this normal virtual memory usage? Do I need to set disk cache size?(Haven't been able to find much on disk cache) I have read many posts but nearly all are problems with physical memory, swap space(file), or swap partition.

top - 18:46:34 up  1:22,  7 users,  load average: 0.69, 0.83, 0.85
Tasks: 161 total,   1 running, 160 sleeping,   0 stopped,   0 zombie
Cpu(s): 15.8%us,  6.6%sy,  0.0%ni, 77.6%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
Mem:   2816560k total,  2263988k used,   552572k free,   269668k buffers
Swap:        0k total,        0k used,        0k free,  1297120k cached


  PID USER      PR  NI  VIRT %MEM  RES  SHR S %CPU    TIME+  COMMAND            
 3544 ubuntu    20   0 1272m  2.9  79m  36m S    1   0:32.63 compiz             
 3571 ubuntu    20   0 1150m  1.0  27m  17m S    0   0:01.31 nautilus           
 2265 root      20   0 1018m  0.1 3940 2744 S    0   0:00.13 console-kit-dae    
 3910 ubuntu    20   0 1015m  0.4  11m 7724 S    0   0:01.12 unity-applicati    
 3916 ubuntu    20   0 1002m  0.2 6600 5200 S    0   0:00.14 unity-files-dae    
 3572 ubuntu    20   0  866m  1.0  27m  13m S    0   0:02.56 nm-applet          
 3374 ubuntu    20   0  834m  1.0  28m  12m S    0   0:02.54 gnome-settings-    
 3986 ubuntu    20   0  808m  0.6  17m 8588 S    0   0:00.30 unity-scope-vid    
 3914 ubuntu    20   0  800m  0.3 8532 6400 S    0   0:00.10 unity-music-dae    
 4128 ubuntu    20   0  742m  3.5  97m  34m S    0   1:57.77 firefox            
 3778 ubuntu    20   0  702m  0.2 4820 3404 S    0   0:02.09 hud-service        
 3725 ubuntu    20   0  698m  0.3 7324 5708 S    0   0:00.07 indicator-datet    
 3952 ubuntu    20   0  654m  0.2 4320 3500 S    0   0:00.04 unity-musicstor    
 3726 ubuntu    20   0  649m  0.2 6488 4880 S    0   0:00.09 indicator-messa    
 3728 ubuntu    20   0  631m  0.4 9.9m 7484 S    0   0:00.07 indicator-print    
 3716 ubuntu    20   0  601m  0.7  20m  11m S    0   0:03.88 unity-panel-ser    
 3731 ubuntu    20   0  599m  0.2 6900 5380 S    0   0:00.08 indicator-sound    
 3729 ubuntu    20   0  598m  0.2 6000 4676 S    0   0:00.07 indicator-sessi    
 4356 ubuntu    20   0  593m  0.6  17m  11m S    0   0:02.96 gnome-terminal 

7 users? Is this correct for a live dvd? I believe I only had 2 users: root and my username when running from my hdd before the format.(I could be wrong)

ubuntu@ubuntu:~$ who
ubuntu   tty5         2012-06-04 17:25
ubuntu   tty6         2012-06-04 17:25
ubuntu   tty2         2012-06-04 17:25
ubuntu   tty4         2012-06-04 17:25
ubuntu   tty3         2012-06-04 17:25
ubuntu   tty1         2012-06-04 17:25
ubuntu   pts/0        2012-06-04 17:32 (:0.0)

ubuntu@ubuntu:~$ sudo ufw status
Status: active

To                         Action      From
--                         ------      ----
22                         DENY        Anywhere
631                        DENY        Anywhere
22                         DENY        Anywhere (v6)
631                        DENY        Anywhere (v6)

ubuntu@ubuntu:~$ sudo ufw app list
Available applications:
  CUPS

ubuntu@ubuntu:~$ sudo ufw app info CUPS
Profile: CUPS
Title: Common UNIX Printing System server
Description: CUPS is a printing system with support for IPP, samba, lpd,
and other protocols.

Port:
  631

netstat -ap (had to remove too long for the post) shows appx 100 connections mostly stream...and about 7 listening which seems bad to me any help there would be appreciated also.

Only 1 running process(top)? Is it normal for all processes to be sleeping?

I've tried to include as much info as I could(limited on what I am allowed to post), if there is anything else I should check please let me know... I want to reinstall Ubuntu 12.04 any tips would be helpful.

2 Answers 2

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What you see is a perfectly healthy desktop.

Virtual memory

Virtual memory has nothing to do with real memory (aka RAM). It's an information that is useful for hackers /Linux developers. Basically on most OS, a process does not map its memory directly to physical memory, but to a virtual memory. If you have enough space, its all in your RAM, but in case you need more space the OS can put parts in the swap file, this is transparent (apart for the performance impact) to the application.

How the virtual memory size is computed is a bit complicated, and I even don't know exactly. But it's full of holes, so you should take this figures as maximum amounts "mapped" but this is not what the process is actually using physically.

Number of users

Again nothing to worry about. You have 6 ubuntu users connected to ttys. This are local connection. You can switch to them by using the key combinations: Ctrl+Alt+Fn with n a number from 1 to 7, 7 being your graphical session.

Netstat

Stream socket are local Unix sockets. Many applications are using those and you should not worry about them. Try the command sudo netstat -tulpen it will give you more interesting results.

And don't worry about "listen" state, it means that you have a service running. The above command will tell you which service is running on which port. As you are using a firewall, as long as the firewall has all ports closed, then a listening service cannot be reached.

Example netstat output:

Proto Recv-Q Send-Q Local Address           Foreign Address         State       User       Inode       PID/Program name
tcp        0      0 127.0.0.1:53            0.0.0.0:*               LISTEN      0          13331       1597/dnsmasq    
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      0          9494        535/sshd        
tcp        0      0 127.0.0.1:631           0.0.0.0:*               LISTEN      0          9880        899/cupsd       
tcp6       0      0 :::22                   :::*                    LISTEN      0          9492        535/sshd        
tcp6       0      0 ::1:631                 :::*                    LISTEN      0          9879        899/cupsd       
udp        0      0 127.0.0.1:53            0.0.0.0:*                           0          13330       1597/dnsmasq    
udp        0      0 0.0.0.0:68              0.0.0.0:*                           0          10498       1136/dhclient   
udp        0      0 0.0.0.0:68              0.0.0.0:*                           0          10492       1115/dhclient   
udp        0      0 0.0.0.0:5353            0.0.0.0:*                           106        9645        915/avahi-daemon: r
udp        0      0 0.0.0.0:42730           0.0.0.0:*                           106        9647        915/avahi-daemon: r
udp6       0      0 :::43066                :::*                                106        9648        915/avahi-daemon: r
udp6       0      0 :::5353                 :::*                                106        9646        915/avahi-daemon: r

Processes state

A process is most of the time idle, it is waiting interactions either from a user, a resource (a file for instance) or another process. If a process would not be sleeping, he will be running and consuming CPU, and if all processes would do so you would not be able to use your system :)

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  • Thank you fro the quick response and the edit to make my post readable(haven't done html coding before) Thanks for the advice on netstat -tulpen much easier results to read than netstat -ap Jun 5, 2012 at 20:09
  • You're welcome, and for information, it is not HTML coding but a special simplified syntax "wiki-like". When editing, you can use either the small toolbar just above the editing area, or the help link to learn this syntax.
    – Huygens
    Jun 6, 2012 at 7:59
  • It's actually more complicated than that, considering that virtual memory is address space that is allocated but not necessarily consumed. Only the latter will show up in 'top' output, whereas 'atop' will show you what's been allocated (and perhaps is even more than your actual RAM due to Linux kernel memory address over-commit).
    – Magellan
    Nov 15, 2012 at 18:26
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This behavior is normal. 7 "users" is not actually 7 users. It is just 7 console sessions that are not doing anything but sitting at a console ready for commands if you switch using [Ctrl]+[Alt]+N. Also, the "sleeping" is normal, as most processes are inactive, but waiting for user interaction, or work delegated from another process. Most processes are sleeping in almost all Linux systems. Also, there are hidden users and groups that do very little except for delegating rights. Also, I am also seeing many network connections. DO not worry. Listening means that they are either ready for data or ready to send data, only a few actually acting. (The Dropbox client, for example, holds its connection LISTENING for the whole session, but it uses practically no bandwidth.)

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  • Thank you for the quick response, I will be reinstalling today. I did a gnu shred of my hard disk(shred -vfz -n 10 /dev/sda1) to make sure there was nothing left behind from the possible fork bomb. Jun 5, 2012 at 20:06

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