vmtouch: portable file cache analyzer

search_compvmtouch is a useful utility to analyze and control the virtual memory used by the filesystem. It works on Unix-ish systems and BSD. It is a portable utility with minimal dependecies in the source code. In addition to understanding cache usage by files, you can also use vmtouch to preload files and speed up subsequent operations. Continue reading vmtouch: portable file cache analyzer

sysstat: check device performance

tux_compsysstat is a collection of utilities to collect performance information and a plethora of other metrics from the system. The utilities are grouped in 4 sets:

  • sar / sadc / sadf : collects system activity information in audit mode (memory, paging, swap…)
  • iostat / tapestat / nfsiostat / cifsiostat : CPU, I/O, partition, disk information
  • mpstat : processor statistics
  • pidstat : process statistics

The full package is written in C and runs very fast.

Continue reading sysstat: check device performance

Process resource usage: more tools

tux_comptop (or htop) is the most popular tool to check per-process memory usage on Linux. However, there are situations where you may want more specific information. For example, what is the total memory used by all the instances of a single process (do you use Chromium based browsers?) or how is X11 (Linux graphics susbsystem) resources used by each process? We will explore 2 unique tools in this article. Continue reading Process resource usage: more tools

dstat: live system information

$ dstat -a
----total-cpu-usage---- -dsk/total- -net/total- ---paging-- ---system--
usr sys idl wai hiq siq| read  writ| recv  send|  in   out | int   csw 
 11   3  85   1   0   0|  51k   58k|   0     0 |   0     0 | 172   864 
  1   0  99   0   0   0|   0  4096B|   0     0 |   0     0 |  81   224 
  0   0 100   0   0   0|   0     0 |   0     0 |   0     0 |  57   174 
  1   0  99   0   0   0|   0     0 |  14k  121B|   0     0 | 104   306 
  1   0  99   0   0   0|   0     0 |  97B  121B|   0     0 | 124   596 
  1   0  99   0   0   0|   0     0 | 218B  172B|   0     0 | 106   407 
  0   0 100   0   0   0|   0     0 | 229B  121B|   0     0 |  84   296 
  1   1  99   0   0   0|   0     0 | 785B  723B|   0     0 | 120   344 
  0   0  99   0   0   0|   0     0 | 163B  121B|   0     0 |  67   208 
  0   0 100   0   0   0|   0     0 |  54B   86B|   0     0 |  67   217 
  0   0 100   0   0   0|   0     0 |   0     0 |   0     0 |  52   161 
  0   0 100   0   0   0|   0     0 |   0     0 |   0     0 |  49   163 
  0   0 100   0   0   0|   0     0 |   0     0 |   0     0 |  56   206 
  0   0 100   0   0   0|   0     0 |   0     0 |   0     0 |  88   304 
  1   0  99   0   0   0|   0     0 |   0     0 |   0     0 | 107   461 
  1   0  99   0   0   0|   0     0 |   0     0 |   0     0 |  60   243 
  0   0 100   0   0   0|   0     0 |   0     0 |   0     0 |  50   148 
  0   0 100   0   0   0|   0     0 |   0     0 |   0     0 |  47   128 
  1   0  99   0   0   0|   0     0 |   0     0 |   0     0 |  90   431 
  1   0  99   0   0   0|   0     0 |   0     0 |   0     0 | 100   408

What if you could have the functionality of vmstat, iostat, mpstat, netstat and ifstat in a single tool? dstat is a top like utility to fetch all the information from a running system and show it in the terminal with regular updates. Continue reading dstat: live system information

csysdig: trace your system

The sysdig utility is a open source tool to trace, explore, capture system state and activity from a running Linux instance, then save, filter and analyze. It is a combination of tools like strace, tcpdump, htop, iftop and lsof. sysdig allows you to dig into system metrics including CPU, memory, disk I/O, network I/O, application activity and more. Continue reading csysdig: trace your system

w: show logged-on users with activities

cool_penguin_smallYes, you read it right! w is the command to show which users are logged-on to the system and what they are doing. It shows much more information than the popular command who. Simple, isn’t it?

$ w
 21:14:32 up 7:48, 3 users, load average: 0.04, 0.15, 0.16
USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT
user1 :0 :0 13:25 ?xdm? 5:43 0.83s /usr/bin/lxsession -s LXDE -e LXDE
user2 pts/0 :0 21:12 0.00s 0.03s 0.00s w
root pts/1 :0 21:14 8.00s 0.03s 0.00s watch free -m

Interesting options:

-p : show the IP address of remote users instead of hostname
user : show information about 'user' only

w is available by default on Ubuntu. Do you know the only other single letter command (technically alias) that works by default on many Linux distros?

Meen more help? Run:

$ man w

i-Nex: hardware information on Linux

i-Nex is a fresh hardware information reporting tool on Linux. The author was inspired by the Windows tool CPU-Z and the the GUI of i-Nex bears a strong resemblance to it. i-Nex is a very powerful tool and provides as much information as CPU-Z, if not more. Capabilities:

  • Basic information of your hardware like like CPU speed, model and L family cache sizes
  • Advanced details like the number of transistors on the die, the multiplier size, the exact voltage and TDW it uses
  • Covers GPU information, audio, drivers and more
  • Software information like distribution, desktop environment etc.
  • Xorg details and kernel information

Drawbacks:

  • i-Nex depends on gambas3 which in turn has tons of dependencies. I am not sure if anyone would want to intall so may packages just to try out a hardware reporting utility.

Install i-Nex on Ubuntu:

$ sudo add-apt-repository ppa:i-nex-development-team/stable
$ sudo add-apt-repository ppa:gambas-team/gambas3
$ sudo apt-get update
$ sudo apt-get install i-nex
Cmdline alternatives to i-Nex on Ubuntu
$ sudo dmidecode -t 4
$ lscpu
$ cat /proc/cpuinfo

Homepage: i-Nex

inxi: fetch system information

inxi is a script that fetches the details of your system, specifically hardware for you. It is quite handy when you need to touch-base with your hardware.The options page extensively details on the numerous things that inxi can do. For simplifying the usage, the authors are working on a GUI as well, though the progress is admittedly slow.

Installation instructions on Ubuntu:

$ sudo apt-get install inxi

To get a list of full options, run:

$ man inxi

Besides showing system information, inxi can show you the weather too! Run:

$ inxi -xxxw

Webpage: inxi