Posts Tagged ‘consumption’

How to find how much power (electricity) consumption a server or PC has?

Friday, November 2nd, 2012

Reading Time: 3minutes

Kill-A-Watt track system power electricty consumption on GNU / Linux servers and FreeBSD
A friend of mine today ask me if I have clue if it is possible to track his home computer Consumption with some piece of Software?

The question is quite interesting, since I run a home server with Linux and it would have been nice if I can exactly track how much electricity per month it  consumes

Now knowing, the answer I first checked online for some kind of software and all I can find something that does something similar but all can find is powertop.

Though powertop is nice Linux tool to keep an eye which program on PC consumes most from overall consumed electricity and order the programs and modules based on electricity consumption it is not providing information on overall electricity consumption.

As the topic seem to be some interesting, I've decided to ask in irc.freenode.net #deiban
Here is a paste from  irssi channel log:

17:21 < hipodilski> hi any idea, how can I find how much electricity a server conmuses per month
17:21 < hipodilski> is there some some kind of software
17:21 -!- digdilem [~digdilem@plague.digdilem.org] has joined #debian
17:22 < babilen> hipodilski: I would recommend an electricity meter rather than software
17:22 -!- tommy_e [~tommy@81.27.221.202] has quit [Ping timeout: 260 seconds]
17:22 < jelly-home> watt meters ftw
17:22 -!- msx [~msx@190.194.114.10] has joined #debian
17:22 -!- blackshirt [~najwa@103.3.223.5] has left #debian []
17:23 < hipodilski> yes but i don't have electricity metter, if there is software it would be interesting to try it
17:23 -!- badiane [~gdurand@D8FF67fa.cst.lightpath.net] has quit [Remote host closed the connection]
17:23 < xand> hipodilski: no, you need a hardware device.
17:23 < jelly-home> now everything can be solved in software, hipodilski
17:23 < jelly-home> not*
17:23 < jelly-home> dammit
17:23 < xand> unless you have a very fancy PSU, software can't find that out
17:23 < babilen> jelly-home: hehe, nice typo !
17:23 < vacuous> hipodilski yes
17:24 < HelloShitty> nsadmin, are you out of ideas for me?
17:24 < vacuous> there's various devices that do it
17:24 -!- firecode [~irc@unaffiliated/firecode] has joined #debian
17:24 < vacuous> you can either get a killawat which are highly innacurate but it might give you a clue
17:24 < vacuous> and they're very cheap too
17:25 < vacuous> you can get a device which measures your entire houses electric, then you just turn off all the appliances and run the
                 server only
17:25 -!- trysten [~trysten@37-251-103-145.FTTH.ispfabriek.nl] has quit [Quit: be back]
17:25  * babilen likes that approach
17:25 < babilen> But this is getting a bit too off-topic. Maybe hipodilski wants to take it to #debian-offtopic
17:25 < vacuous> or you can keep all fridges on, check what the reading is and then negate that from the total
17:25 < hipodilski> yes thanks 🙂
 

The answer makes it clear right of time of writing this post there is no software for Linux or BSD that keeps track electricity consumption daily or monthly

I've googled to see what is Kill-A-Watt hardware? and found fuzzy named device Kill-A-Watt for sale on ThinkGeek's website for the not so expensive 24.99$

To use Kill-A-Watt device is to be connected inside the power plug and then PC or Server has to be plugged into  Kill-A-Watt dev. I've red also (while researching) many Intelligent UPS devs has support for keeping log of discharged energy, so just buying a good UPS with web administrator or even a cheap one providing statistical information of UPS use via serial port should be another alternative to track ur server consumption.

Speeding up Apache through apache2-mpm-worker and php5-cgi on Debian / How to improve Apache performance and decrease server memory consumption

Friday, March 18th, 2011

Reading Time: 5minutes

speeding up apache through apache2-mpm-worker and php5-cgi on Debian Linux / how to improve apache performance and decrease server responce time
By default most Apache running Linux servers on the Internet are configured to use with the mpm prefork apache module
Historically prefork apache module is the predecessor of the worker module therefore it's believed to be a way more tested and reliable, if you need a critical reliable webserver configuration.

However from my experience by so far with the Apache MPM Worker I can boldly say that many of the rumors concerning the unreliabity of apache2-mpm-worker are just myths.

The old way Apache handles connections e.g. the mod prefork is the well known way that high amount of the daemons on Linux and BSD are still realying on.
When prefork is a used by Apache, every new TCP/IP connection arriving at your Linux server on the Apache configured port let's say on port 80 is being served by Apache in a way that the Apache process (mother process) parent does fork a new Apache parent copy in order to serve the new request.
Thus by using the prefork Apache needs to fork new process (if it doesn't have already an empty forked one waiting for connections) and serve the HTTP request of the new client, after the request of the client is completed the newly forked Apache usually dies (even though it again depends on the way the Apache server is configured via the Apache configuration – apache2.conf / httpd.conf etc.).

Now you can imagine how slow and memory consuming it is that all the time the parent Apache process spawns new processes, kills old ones etc. in order to fulfill the client requests.

Now just to compare the Apace mpm prefork does not use the old forking way, but relies on a few Apache processes which handles all the requests without constantly being destroyed and recreated like with the prefork module.
This saves operations and system resources, threaded programming has already been proven to be more efficient way to handle tasks and is heavily adopted in GUI programming for instance in Microsoft Windows, Mac OS X, Linux Gnome, KDE etc.

There is plenty of information and statistical data which compares Apache running with prefork and respectively worker modules online.
As the goal of this article is not to went in depths with this kind of information I would not say more on it but let you explore online a bit more about them in case if you're interested.

The purpose of this article is to explain in short how to substitute the Apache2-MPM-Prefork and how your server performance could benefit out of the use of Apache2-MPM-Worker.
On Debian the default Apache process serving module in Apache 1.3x,Apache 2.0x and 2.2x is prefork thus the installation of apache2-mpm-worker is not "a standard way" to install Apache

Deciding to swith from the default Debian apache-mpm-prefork to apache-mpm-worker is quite a serious and responsible decision and in some cases might cause troubles, if you have decided to follow my article be sure to consider all the possible negative consequences of switching to the apache worker !

Now after having said a bunch of info which might be not necessary with the experienced system admin I'll continue on with the steps to install the apache2-mpm-worker.

1. Install the apache2-mpm-worker

debian:~# apt-get install apache2-mpm-worker php5-cgi
Reading state information... Done
The following packages were automatically installed and are no longer required:
The following packages will be REMOVED apache2-mpm-prefork libapache2-mod-php5
The following NEW packages will be installed apache2-mpm-worker
0 upgraded, 1 newly installed, 2 to remove and 46 not upgraded.
Need to get 0B/259kB of archives.After this operation, 6193kB disk space will be freed.

As you can notice in below's text confirmation which will appear you will have to remove the apache2-mpm-prefork and the apache2-mpm-worker modules before you can proceed to install the apache2-mpm-prefork.

You might ask yourself if I remove my installed libphp how would I be able to use my Apache with my PHP based websites? And why does the apt package manager requires the libapache2-mod-php5 to get removed.
The explanation is simple apache2-mpm-worker is not thread safe, in other words scripts which does use the php fork(); function would not work correctly with the Apache worker module and will probably be leading to PHP and Apache crashes.
Therefore in order to install the apache mod worker it's necessary that no libapache2-mod-php5 is existent on the system.
In order to have a PHP installed on the server again you will have to use the php5-cgi deb package, this is the reason in the above apt-get command I'm also requesting apt to install the php5-cgi package next to apache2-mpm-worker.

2. Enable the cgi and cgid apache modules

debian:~# a2enmod cgi
debian:~# a2enmod cgid

3. Activate the mod_actions apache modules

debian:~# cd /etc/apache2/mods-enabled
debian:~# ln -sf ../mods-available/actions.load
debian:~# ln -sf ../mods-available/actions.conf

4. Add configuration options in order to enable mod worker to use the newly installed php5-cgi

Edit /etc/apache2/mods-available/actions.conf vim, mcedit or nano (e.g. your editor of choice and add inside:

&ltIfModule mod_actions.c>
Action application/x-httpd-php /cgi-bin/php5
</IfModule>

After completing all the above instructions, you might also need to edit your /etc/apache2/apache2.conf to tune up, how your Apache mpm worker will serve client requests.
Configuring the <IfModule mpm_worker_module> in apache2.conf is necessary to optimize your newly installed mpm_worker module for performance.

5. Configure the mod_worker_module in apache2.conf One example configuration for the mod worker is:

<IfModule mpm_worker_module>
StartServers 2
MaxClients 150
MinSpareThreads 25
MaxSpareThreads 75
ThreadsPerChild 25
MaxRequestsPerChild 0
</IfModule>

Consider the fact that this configuration is just a sample and it's in no means configured for serving Apache requests for high load Apache servers and you need to further play with the values to have a good results on your server.

6. Check that all is fine with your Apache configurations and no syntax errors are encountered

debian:~# /usr/sbin/apache2ctl -t
Syntax OK

If you get something different from Syntax OK track the error and fix it before you're ready to restart the Apache server.

7. Now restart the Apache server

debian:~# /etc/init.d/apache2 restart

All should run fine and hopefully your PHP scripts should be interpreted just fine through the php5-cgi instead of the libapache2-mod-php5.
Using the /usr/bin/php5-cgi will increase with some percentage your server CPU load but on other hand will drasticly decrease the Webserver memory consumption.
That's quite logical because the libapache2-mod-hp5 is loaded once during apache server whether a new instance of /usr/bin/php5-cgi is invoked during each of Apache requests via the mod worker.

There is one serious security flow coming with php5-cgi, DoS against a server processing scripts through php5-cgi is much easier to be achieved.
An example for a denial attack which could affect a website running with mod worker and php5-cgi, could be simulated from a simple user with a web browser which holds up the f5 or ctrl + r browser page refresh buttons.
In that case whenever php5-cgi is used the CPU load would rise drastic, one possible solution to this denial of service issues is by installing and using libapache2-mod-evasive like so:

8. Install libapache2-mod-evasive

debian:~# apt-get install libapache2-mod-evasive
The Apache mod evasive module is a nice apache module to minimize HTTP DoS and brute force attacks.
Now with mod worker through the php5-cgi, your apache should start serving requests more efficiently than before.
For some performance reasons some might even want to try out the fastcgi with the worker to boost the Apache performance but as I have never tried that I can't say how reliable a a mod worker with a fastcgi would be.

N.B. ! If you have some specific php configurations within /etc/php5/apache2/php.ini you will have to set them also in /etc/php5/cgi/php.ini before you proceed with the above instructions to install Apache otherwise your PHP scripts might not work as expected.

Mod worker is also capable to work with the standard mod php5 Apache module, but if you decide to go this route you will have to recompile your PHP lib manually from source as in Debian this option is not possible with the default php library.
This installation worked fine on Debian Lenny but suppose the same installation should work fine on Debian Squeeze as well as Debian testing/unstable.
Feedback on the afore-described mod worker installation is very welcome!

SWITCH OFF your Mobile Phone and TV at night to save energy!!!

Thursday, June 7th, 2012

Reading Time: 3minutesTURN OFF YOUR MOBILE PHONE AT NIGHT to SAVE ENERGY and MONEY

We’re constantly being said to reduce energy consupmtion, they sell us new bulbs to save energy, new TVs with energy saving. The newer the computer equipment microwaves or whatever home electrical equipment we buy the more it is said to be saving energy.

So far so good it is true we can reduce energy consumption by producing gadgets which consume less. However there are also another approach to the “green problem” which we never are said about.

It is rather simply instead of saving energy on technology base, we can save energy on physical base. One simple thing to do to save energy with no need to spend money on latest advacement gadgets is to simply make it the old school way.

a -= Learn to switch off your lamps and home equipment whenever its not necessery

If you’re about to go to sleep, you can simply switch off the mobile and use a mechanical clock to wake you up on the morning, this way you have 3 benefits.

1; Less energy will be discharged by the mobile in the time you’re not awake, so you don’t need to charge so frequently the battery and therefore you will draw less energy from the Electrical network hence saving energy.

2; You will not be radiated with a bit less radiation produced by the Mobile phone in order to stay connected to the GSM local located cell.

Though the good this does will not be dramatical it for sure will be better for your health than if the mobile is switched on the whole night.

3; You will not be awakened in morning by some crazy person who just decided to call you early in the morning.
Often this morning unexpected and desired phone calls make you jump off the bed rapidly and hence giving a large dose of stress to your organizm.

-=- Of course switching off the mobile has some disadvantages if you can receive a crucial phone calls during all time of day or night you can’t afford to simply switch off the mobile, this is however not true for most people who work in an OFF-ICE.People working in offices can simply wake up at a scheduled time, get a shower do their morning hygiene and jump to a car or bus to the office so the need for having the mobile switched ON at night is not really needed.

Of course thinking in the same direction, it is logical that switching off the computer earlier when not needed, the wireless home router or the TV is another place from where a huge energy savings can be achieved.

If large amount of people re-learn their energy in-efficient habits to be more energy cautios a HUGE amounts of energy can be saved. This of course can have a positive impact on the monthly energy bills and hence can save you money in monthly expenses.

The TV is surely another big energy draining source, many people have the habit to sleep with a Television switched on. Besides this has a negative impact on the conscious since vast amounts of information are being stored and processed by the conscious and unconscious mind, also the lights emitted from the TV screen prevents the persons body to not have a pieceful rest.

Its rather stupid that companies are constantly ranting on how they improve their products to be energy friendly but they don’t invest even a penny to educate the masses that energy saving does not only depend on how good the technology is produced to save energy but also on how much the people are educated how to use the technology with energy saving in mind.Probably there are plenty of other ways a households can change their habits to save energy. I’ll be glad to hear some other suggestions ,,,

How to find out all programs bandwidth use with (nethogs) top like utility on Linux

Friday, September 30th, 2011

Reading Time: 3minutes
Just run across across a super nice top like, program for system administrators, its called nethogs and is definitely entering my “l337” admin outfit next to tools like iftop, nettop, ettercap, darkstat htop, iotop etc.

nethogs is ultra easy to use, to get immediately in console statistics about running processes UPLOAD and DOWNLOAD bandwidth consumption just run it:

linux:~# nethogs

Nethogs screenshot on Linux Server with Nginx
Nethogs running on Debian GNU/Linux serving static web content with Nginx

If you need to check what program is using what amount of network bandwidth, you will definitely love this tool. Having information of bandwidth consumption is also viewable partially with iftop, however iftop is unable to track the bandwidth consumption to each process using the network thus it seems nethogs is unique at what it does.

Nethogs supports IPv4 and IPv6 as well as supports network traffic over ppp. The tool is available via package repositories for Debian GNU/Lenny 5 and Debian Squeeze 6.

To install Nethogs on CentOS and Fedora distributions, you will have to install it from source. On CentOS 5.7, latest nethogs which as of time of writting this article is 0.8.0 compiles and installs fine with make && make install commands.

In the manner of thoughts of network bandwidth monitoring, another very handy tool to add extra understanding on what kind of traffic is crossing over a Linux server is jnettop
jnettop shows which hosts/ports is taking up the most network traffic.
It is available for install via apt in Debian 5/6).

Here is a screenshot on jnettop in action:

Jnettop check network traffic in console

To install jnettop on latest Fedoras / CentOS / Slackware Linux it has to be download and compiled from source via jnettop’s official wiki page
I’ve tested jnettop install from source on CentOS release 5.7 and it seems to compile just fine using the usual compile commands:

[root@prizebg jnettop-0.13.0]# ./configure
...
[root@prizebg jnettop-0.13.0]# make
...
[root@prizebg jnettop-0.13.0]# make install

If you need to have an idea on the network traffic passing by your Linux server distringuished by tcp/udp/icmp network protocols and services like ssh / ftp / apache, then you will definitely want to take a look at nettop (if of course not familiar with it yet).
Nettop is not provided as a deb package in Debian and Ubuntu, where it is included as rpm for CentOS and presumably Fedora?
Here is a screenshot on nettop network utility in action:

Nettop server traffic division by protocol screenshot
FreeBSD users should be happy to find out that jnettop and nettop are part of the ports tree and the two can be installed straight, however nethogs would not work on FreeBSD, I searched for a utility capable of what Nethogs can, but couldn’t find such.
It seems the only way on FreeBSD to track bandwidth back and from originating process is using a combination of iftop and sockstat utilities. Probably there are other tools which people use to track network traffic to the processes running on a hos and do general network monitoringt, if anyone knows some good tools, please share with me.

What is Xorg’s server DPMS module for? And how to use it to reduce your computer power consumption

Thursday, April 21st, 2011

Reading Time: 1minute
As I’m manually configuring a Xserver via xorg.conf I have noticed a block of code in:

Section "Monitor"
Identified "Generic Monitor"
Option "DPMS"
EndSection
That triggered my curiousity to research further what is DPMS . A very quick google search revealed that DPMS’s purpose is to communicate to communicate between the monitor and the computer, to make the computer turn off the (CRT or LED) based monitor if the computer is not used

Thus in short to rephrase DPMS is a power saving handy Xorg feature. I many custom configured xorg.conf like the mine I’m building right now does not include DPMS as many people doesn’t have idea what DPMS is and how to enable it.

DPMS is also an interface to the Energy start power-saving capability if not all, most of the modern day monitor screens.

DPMS enables the Xserver to control automatically the computer screen and thus reduces the overall computer power consumption.

To enable the use of DPMS on my Linux, all I had to do is place a couple of configuration directives in my xorg.conf .:
Here is how I enabled DPMS in my Xorg server:

1. Edit with a text editor /etc/X11/xorg.conf

2. Find the Monitor Section , e.g.:

Section "Monitor"
....
EndSection

3. Add inside the Monitor Section Options "DPMS" "true"

4. Lookup for the ServeryLayout section , e.g.:

Section "ServerLayout"
...
EndSection

5. Place inside the ServerLayout section For instance the following options:

Option "StandbyTime" "20"
Option "SuspendTime" "10"
Option "OffTime "25"

You might like to change the options StandbyTime, SuspendTIme or OffTime to match your likings.
6. As a last step restart the Xorg server.

Press Ctrl+Alt+BackSpace or by issuing:

host:~# pkill -HUP X

Test that DPMS is loaded properly by reviewing /var/log/Xorg.0.log for example:

host:~# grep -i /var/log/Xorg.0.log
(II) Loading extensions DPMS