Posts Tagged ‘memory’

Check TOP Memory and CPU use with ps command on Linux

Sunday, October 22nd, 2017


There are plenty of software to check the GNU / Linux Server Load bottlenecks such as top / tload / slabtop / htop but for shell scripting purposes or perl  / python / ruby automation Dev Ops scripts and various Web and Middleware Tasks it is always better to know how to print list the TOP Memory and CPU consumption processes on Linux.

Below are two easy commands you can use to check out, which process is the most memory hungry and which running daemon (MySQL / PostgreSQL / Apache whatever) is the overloading your *nix server CPU.

TOP Memory use sorted by process memory max consumption


ps aux  | awk '{print $6/1024 " MBtt" $11}'  | sort -n


TOP CPU use sorted y running daemon

ps -eo pcpu,pid,user,args | sort -k 1 -r | head -10

Enjoy 🙂

Graphic tool to get Hardware Information on Linux / How to view Hardware Information easy in Linux

Tuesday, October 3rd, 2017







If you are a console maniac like myself, perhaps you never think that you might need anything graphical besides to view hardware information on Linux, but as we're growing older sometimes it becomes much less easier to just use a graphical tool that can show us all the information we need regarding a Notebook / Desktop PC with Linux or even Server machine with enabled Graphical Environment with a brand new installed GNU / Linux whatever version (I hope you don't own server with running Xorg / Gnome / Mate / Xfce etc. as that's pretty much a waste of hardware resource and opens a dozen of other security risks for the server running services ).



 There are at least 2 ways to quickly check hardware on both PC WorkStation or Server, the easiest and quickest for PC / Notebook Linux users if you have installed GTK libraries or Gnome Desktop Environment is with;


LSHW-GTK is simply a GTK frontend over the command line tool for hardware information gathering LSHW



HardInfo – is a small application that displays information about your hardware and operating system. Currently it knows about PCI, ISA PnP, USB, IDE, SCSI, Serial and parallel port devices.

1. Howto Install LSHW-GTK / HardInfo on Debian / Ubuntu / Mint GNU / Linux to easy view hardware information

To install both of them on Debian / Ubuntu GNU / Linux, run:

apt-get install –yes lshw lshw-gtk hardinfo


2. Howto install LSHW-GTK on Fedora, CentOS and OpenSuSE Linux to view easy hardware information

On RedHat RPM based Linux distributions, the package to install is called lshw-gui

Install with yum RPM package manager:

yum install –yes lshw lshw-gui  hardinfo

3. Run lshw-gtk / hardinfo

Again, find them and run from GUI environment menus or run manually like in below example:

$ lshw-gtk



$ hardinfo


As you see hardinfo is really interactive and it gives you pretty much all the information, you might need, the only information that was missing at my case and I guess, that would happen to others is information about the SSD Hard Disk, which   180GB

HardInfo is really amazing program as it even includes various common Benchmark Tests and comparison with other Computers:


True that the tests, are pretty simple but still could be useful.

Now run it either from GNOME / Cinnamon (The default graphical environment of Debian Linux) or PLASMA (The new name for the second most popular Linux Graphical Environment – KDE desktop environment)


$ lshw

Here is few more screenshots from hardware info reported from my ThinkPad T410 Laptop Running Debian 9 Stretch at the moment.


MotherBoard -> BIOS Information

(thatnks God this old but gold Thinkpad T420 business notebook does not run UEFI substitute for BIOS 🙂


CPU Information (with all the supported CPU capabilities (extensions)


Host Bridge Info


Thinkpad BATTERY (45N1005) Info


By the way another Way to GUI View your Computer is to just generate HTML from lshw command line tool (as it supports export to HTML), here is how:


$ lshw -html > ~/hardware-specs.html

Then just open it with Browser, for example I like GNOME Epiphany browser, so I'll read HTML with it:


$ epiphany ~/hardware-specs.html


The great thing about generating HTML report for hardware is that on Staging / Production / Development servers which you inherited from some other administrator who for some reason (laziness 🙂 ) didn't left necessery documentation, you can easily map the machine hardware and even if it is a group of machines, you can automate report generation for all of them write a short script that parses the data on each of the HTML reports and finally creates a merged document with main important information about hardware of a cluster of computers etc.

If you still want to stick to console run the console version of lshw or use dmidecode or lshw:


$ lshw

hipo@jericho:~$ lshw
WARNING: you should run this program as super-user.
    description: Computer
    width: 64 bits
    capabilities: smp vsyscall32
       description: Motherboard
       physical id: 0
          description: System memory
          physical id: 0
          size: 7870MiB
          product: Intel(R) Core(TM) i7-2640M CPU @ 2.80GHz
          vendor: Intel Corp.
          physical id: 1
          bus info: cpu@0
          size: 891MHz
          capacity: 3500MHz
          width: 64 bits
          capabilities: fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp x86-64 constant_tsc arch_perfmon pebs bts nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm epb tpr_shadow vnmi flexpriority ept vpid xsaveopt dtherm ida arat pln pts cpufreq
          description: Host bridge
          product: 2nd Generation Core Processor Family DRAM Controller
          vendor: Intel Corporation
          physical id: 100
          bus info: pci@0000:00:00.0
          version: 09
          width: 32 bits
          clock: 33MHz
             description: PCI bridge
             product: Xeon E3-1200/2nd Generation Core Processor Family PCI Express Root Port
             vendor: Intel Corporation
             physical id: 1
             bus info: pci@0000:00:01.0
             version: 09
             width: 32 bits
             clock: 33MHz
             capabilities: pci normal_decode bus_master cap_list
             configuration: driver=pcieport
             resources: irq:24 ioport:5000(size=4096) memory:f0000000-f10fffff ioport:c0000000(size=301989888)
           *-generic UNCLAIMED
                description: Unassigned class
                product: Illegal Vendor ID
                vendor: Illegal Vendor ID
                physical id: 0
                bus info: pci@0000:01:00.0
                version: ff
                width: 32 bits
                clock: 66MHz
                capabilities: bus_master vga_palette cap_list
                configuration: latency=255 maxlatency=255 mingnt=255
                resources: memory:f0000000-f0ffffff memory:c0000000-cfffffff memory:d0000000-d1ffffff ioport:5000(size=128) memory:f1000000-f107ffff
             description: VGA compatible controller
             product: 2nd Generation Core Processor Family Integrated Graphics Controller
             vendor: Intel Corporation
             physical id: 2
             bus info: pci@0000:00:02.0
             version: 09
             width: 64 bits
             clock: 33MHz
             capabilities: vga_controller bus_master cap_list rom
             configuration: driver=i915 latency=0
             resources: irq:30 memory:f1400000-f17fffff memory:e0000000-efffffff ioport:6000(size=64) memory:c0000-dffff
             description: Communication controller
             product: 6 Series/C200 Series Chipset Family MEI Controller #1
             vendor: Intel Corporation
             physical id: 16
             bus info: pci@0000:00:16.0
             version: 04
             width: 64 bits
             clock: 33MHz
             capabilities: bus_master cap_list
             configuration: driver=mei_me latency=0
             resources: irq:27 memory:f3925000-f392500f
             description: Serial controller
             product: 6 Series/C200 Series Chipset Family KT Controller
             vendor: Intel Corporation
             physical id: 16.3
             bus info: pci@0000:00:16.3
             version: 04
             width: 32 bits
             clock: 66MHz
             capabilities: 16550 bus_master cap_list
             configuration: driver=serial latency=0
             resources: irq:19 ioport:60b0(size=8) memory:f392c000-f392cfff
             description: Ethernet interface
             product: 82579LM Gigabit Network Connection
             vendor: Intel Corporation
             physical id: 19
             bus info: pci@0000:00:19.0
             logical name: enp0s25
             version: 04
             serial: 00:21:cc:cc:b2:27
             capacity: 1Gbit/s
             width: 32 bits
             clock: 33MHz
             capabilities: bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
             configuration: autonegotiation=on broadcast=yes driver=e1000e driverversion=3.2.6-k firmware=0.13-3 latency=0 link=no multicast=yes port=twisted pair
             resources: irq:25 memory:f3900000-f391ffff memory:f392b000-f392bfff ioport:6080(size=32)
             description: USB controller
             product: 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2
             vendor: Intel Corporation
             physical id: 1a
             bus info: pci@0000:00:1a.0
             version: 04
             width: 32 bits
             clock: 33MHz
             capabilities: ehci bus_master cap_list
             configuration: driver=ehci-pci latency=0
             resources: irq:16 memory:f392a000-f392a3ff
             description: Audio device
             product: 6 Series/C200 Series Chipset Family High Definition Audio Controller
             vendor: Intel Corporation
             physical id: 1b
             bus info: pci@0000:00:1b.0
             version: 04
             width: 64 bits
             clock: 33MHz
             capabilities: bus_master cap_list
             configuration: driver=snd_hda_intel latency=0
             resources: irq:29 memory:f3920000-f3923fff
             description: PCI bridge
             product: 6 Series/C200 Series Chipset Family PCI Express Root Port 1
             vendor: Intel Corporation
             physical id: 1c
             bus info: pci@0000:00:1c.0
             version: b4
             width: 32 bits
             clock: 33MHz
             capabilities: pci normal_decode cap_list
             configuration: driver=pcieport
             resources: irq:16
             description: PCI bridge
             product: 6 Series/C200 Series Chipset Family PCI Express Root Port 2
             vendor: Intel Corporation
             physical id: 1c.1
             bus info: pci@0000:00:1c.1
             version: b4
             width: 32 bits
             clock: 33MHz
             capabilities: pci normal_decode bus_master cap_list
             configuration: driver=pcieport
             resources: irq:17 memory:f3800000-f38fffff
                description: Wireless interface
                product: Centrino Advanced-N 6205 [Taylor Peak]
                vendor: Intel Corporation
                physical id: 0
                bus info: pci@0000:03:00.0
                logical name: wlp3s0
                version: 34
                serial: 26:ad:26:50:f1:db
                width: 64 bits
                clock: 33MHz
                capabilities: bus_master cap_list ethernet physical wireless
                configuration: broadcast=yes driver=iwlwifi driverversion=4.9.0-3-amd64 firmware= ip= latency=0 link=yes multicast=yes wireless=IEEE 802.11
                resources: irq:28 memory:f3800000-f3801fff
             description: PCI bridge
             product: 6 Series/C200 Series Chipset Family PCI Express Root Port 4
             vendor: Intel Corporation
             physical id: 1c.3
             bus info: pci@0000:00:1c.3
             version: b4
             width: 32 bits
             clock: 33MHz
             capabilities: pci normal_decode bus_master cap_list
             configuration: driver=pcieport
             resources: irq:19 ioport:4000(size=4096) memory:f3000000-f37fffff ioport:f1800000(size=8388608)
             description: PCI bridge
             product: 6 Series/C200 Series Chipset Family PCI Express Root Port 5
             vendor: Intel Corporation
             physical id: 1c.4
             bus info: pci@0000:00:1c.4
             version: b4
             width: 32 bits
             clock: 33MHz
             capabilities: pci normal_decode bus_master cap_list
             configuration: driver=pcieport
             resources: irq:16 ioport:3000(size=4096) memory:f2800000-f2ffffff ioport:f2000000(size=8388608)
                description: System peripheral
                product: MMC/SD Host Controller
                vendor: Ricoh Co Ltd
                physical id: 0
                bus info: pci@0000:0d:00.0
                version: 08
                width: 32 bits
                clock: 33MHz
                capabilities: bus_master cap_list
                configuration: driver=sdhci-pci latency=0
                resources: irq:16 memory:f2800000-f28000ff
             description: USB controller
             product: 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1
             vendor: Intel Corporation
             physical id: 1d
             bus info: pci@0000:00:1d.0
             version: 04
             width: 32 bits
             clock: 33MHz
             capabilities: ehci bus_master cap_list
             configuration: driver=ehci-pci latency=0
             resources: irq:23 memory:f3929000-f39293ff
             description: ISA bridge
             product: QM67 Express Chipset Family LPC Controller
             vendor: Intel Corporation
             physical id: 1f
             bus info: pci@0000:00:1f.0
             version: 04
             width: 32 bits
             clock: 33MHz
             capabilities: isa bus_master cap_list
             configuration: driver=lpc_ich latency=0
             resources: irq:0
             description: SATA controller
             product: 6 Series/C200 Series Chipset Family 6 port SATA AHCI Controller
             vendor: Intel Corporation
             physical id: 1f.2
             bus info: pci@0000:00:1f.2
             version: 04
             width: 32 bits
             clock: 66MHz
             capabilities: storage ahci_1.0 bus_master cap_list
             configuration: driver=ahci latency=0
             resources: irq:26 ioport:60a8(size=8) ioport:60bc(size=4) ioport:60a0(size=8) ioport:60b8(size=4) ioport:6060(size=32) memory:f3928000-f39287ff
             description: SMBus
             product: 6 Series/C200 Series Chipset Family SMBus Controller
             vendor: Intel Corporation
             physical id: 1f.3
             bus info: pci@0000:00:1f.3
             version: 04
             width: 64 bits
             clock: 33MHz
             configuration: driver=i801_smbus latency=0
             resources: irq:18 memory:f3924000-f39240ff ioport:efa0(size=32)
          physical id: 2
          logical name: scsi1
          capabilities: emulated
             description: DVD-RAM writer
             product: DVDRAM GT50N
             vendor: HL-DT-ST
             physical id: 0.0.0
             bus info: scsi@1:0.0.0
             logical name: /dev/cdrom
             logical name: /dev/cdrw
             logical name: /dev/dvd
             logical name: /dev/dvdrw
             logical name: /dev/sr0
             version: LT20
             capabilities: removable audio cd-r cd-rw dvd dvd-r dvd-ram
             configuration: ansiversion=5 status=nodisc
WARNING: output may be incomplete or inaccurate, you should run this program as super-user.


Enjoy Life ! 🙂

Upgrade old crappy Windows 7 32 bit to Windows 10 32 bit, post install fixes and impressions / How to enter Safe Mode in Windows 10

Wednesday, June 28th, 2017


However as I've been upgrading my sister's computer previously running Windows 7 to Windows 10 (the process of upgrading is really simple you just download Windows-Media-Creation-tool from Microsoft website and the rest comes to few clicks (Accept Windows 10 User Agreement, Create current install  restore point (backup) etc.) and waiting some 30 minutes or so for the upgrade to complete.


Then it was up to downloading some other updates on a few times and restarting the computer, each time the upgrades were made and all the computer was ready. I've installed Avira (AntiVirus) as I usually do on new PCs and downloaded a bunch of anti-malware (MalwareBytes / Rfkill  / Zemanta)  to make sure that the old upgraded  WIndows was not already infected before the upgrade and I've found a bunch of malware, that got quickly cleared up.

Anyways I've tried also another tool called ReimagePlus – Online Computer Repair in order to check whether there are no some broken WIndows system files after the upgrade

(here I have to say I've done that besides running in an Administrator command prompt (cmd.exe) and running

sfc /scannow

command to check base system files integrity, which luckily showed no problems with the Win base system files.

ReimagePlus however showed some failed services and some failed programs that were previously installed from Windows 7 before the upgrade and even it showed indication for Trojan present on computer but since ReImagePlus is a payed software and I didn't have the money to spend on it, I just proceeded to clean up what was found manually.

After that the computer ran fine, with the only strange thing that some data was from hard drive was red a bit too frequently, after a short call with a close friend (Nomen) – thx man, he suggested that the frequenty hdd usage might be related to Windows Search Indexing service database rebuilt and he adviced me to disable it which I did following this article How to speed up Windows by disabling Search Index Service.

One issue worthy to mention  stumbled upon after the upgrade was problems with Windows Explorer which was frequently crashing and "restarting the Desktop", but once, I've enabled all upgrades from Microsoft and Applied them after some update failures and restarts, once all was up2date to all latest from Microsoft, Explorer started working normally.

In the mean time while Windows Explorer was crashing in order to browse my file system I used the good old Win Total Command or Norton Commander for Windows – WinNC (with its most cool bizzarre own File Explorer tool).


As I wanted to run a MalwareBytes scan and Antivirus under Windows Safe-Mode, I tried entering it by restarting the Computer and pressing F8 a number of times before the Windows boot screen but this didn't work as Safe-Mode boot was changed in Windows 10 to be callable in another way because of some extra Windows Boot speed up optimizations, in short the easiest way I found to enter Windows 10 Safe Mode was to Hit Start Button -> Choose Restart PC and keep pressed SHIFT button simultaneously
that calls a menu that gives you some restore options, along with safe mode options for those who want to read more on How to Enter Safe mode (Command Prompt) on Windows 10 – please read this article.


Once the upgrade was over and all below done unfortunately I've realized her previously installed WIndows 7 is x86 (32 bit) version and the Acer notebook 5736Z where it is being installed is actually X64 (64 bit), hence I've decided to upgrade my dear sis computer to a 64 Bit Windows 10 and researched online whether, there is some tool that is capable to upgrade WIndows 10 from 32 bit to Windows 10 64 bit just to find out the only option is to either use some program to creaty a backup of files on the PC or to manually copy files to external hard drive and reinstall with a Windows 10 64 bit bootable USB Flash or CD / DVD image, so I took my USB flash and used again Windows Media Creation Tool to burn Windows and re-install with the 64 bit iso.

If you're wonder about why I choose to re-install finally Win 10 32 bit with Win 64 bit, because you might think performance difference might be not really so dramatic, then I have to say the Acer notebook is equipped with 4 Gigabytes of RAM Memory and Windows 10 32bit  (Pro) could recognize a maximum of 3 Gigabytes (2.9 GB if I have to be precise) and 1 Gigabyte of memory stays totally unusued all the time with  Winblows 10 32 bit.


I've tried my best actually to not loose time to fully upgrade Windows 7 (32 bit) -> Windows 10 (64 bit) but to make Windows 7 32 bit Windows to use more than the default Limitation of 3GB of memory by using this thirt party PAE Externsion Kernel Patch
which is patching the Windows Kernel to extend the Windows support for PCs with up to 128 GB of memory however it turned out that this Patch file is not compatible with my Windows Kernel version once I followed readme instructions.

It seems the PAE (Physical Address Extension) is supported by default  by Microsoft only on 32 bit Windows Server 10 to read more on the PAE if interested give a look here.

Well that's all folks, the rest I did was to just boot from the USB drive just burned and re-install WIndows and copy my files from User profile / Downloads / Pictures / Music etc. to the same locations on the new installed Windows 10 professional 64 bit and enjoy the better performance.

Howto install XCache Debian on GNU / Linux to accelerate Apache Webserver – XCache Best alternative to outdated PHP cacher EAccelerator

Thursday, February 26th, 2015

I was using Eaccelerator until recently on all Apache / PHP / MySQL  (LAMP) web-servers as a caching engine (Webserver accelerator) across all Debian GNU / Linux Lenny / Squeeze / Etch servers.
However recently, I've noticed in phpinfo output on some of the Debian hosts, that eaccelerator was loaded but showed:

 Caching Enabled false



Our servers are quite busy serving about 50 000 to 100 000 requests and thus not having enabled caching puts a lot of extra load on the CPU and eats a lot of memory which were usually saved by eAccelerator.
Logically I tried fixing the issues following some Stackoverflow threads recommendations such as this one but didn't work I tried playing manually spending hours trying to make eaccelerator run again and as a final mean, I even tried to upgrade eaccelerator to newer version but noticed the latest available eaccelerator version 0.9.6 was 2.5 years old (from 03.09.2012). Thus while there is no new release, just make s so just to make sure I didn't break the module with (default Debian bundled distribution package which is also installed on the servers)  re-installed eAccelerator from source 

This didn't worked either and since I was totally pissed off by the worsened systems performance (CPU load increased with to 10-30%) per server, I looked for some alternatives I can use and in the mean time I learned a bit more about history of PHP Accelerators, I learned some interesting things such as that  ionCube (PHPA) was the  first PHP Accelerator Apache like module (encoding PHP code),  created in 2001, later it become inspirational for  birth to PHP-APC (Alternative PHP Cache) Apache module. 
There is also Zend Opcache PHP accelerator (available since PHP 5.5 onwards)  but since Zend OpCache caches well PHP Zend written PHP code and servers run PHP 5.4 + sites are not using Zend PHP Framewosk  this was an option.
Further investigation lead me to MMCache which is already too obsolete (latest release is from 2013), PHPExpress – PHP Encoder which  was said to run on Windows, Linux, FreeBSD, NetBSD, Mac OS X, and Solaris) but already looks dead as there were no new releases since January 2012) and finally Lighttpd's XCache.

To give you an idea on what exactly is the difference between Apache Webserver with PHP-APC Caching or other PHP Cacher enabled and the Standard way PHP Interprets PHP scripts below is a diagram:


Obviously my short research shows that from all the available PHP Cache Encoder / Accelerators only ones that seemed to be recently updated (under active development) are APC and XCache.
I've already used PHP-APC earlier on some servers and was having having some random Apache Webservers crashes and weird empty pages with some PHP pages and besides that APC is known to give lower speed in PHP caching than Eaccelerator and XCache, leaving me with the only and logical choise to use XCACHE.

Here is how Xcache developers describe their opcacher:

XCache is a free, open source operation code cacher, it is designed to enhance the performance of PHP scripts execution on servers. It optimizes the performance by eliminating the compilation time of PHP code by caching the compiled version of code into the memory and this way the compiled version loads the PHP script directly from the memory. This will surety accelerate the page generation time by up to 5 times faster and also optimizes and increases many other aspects of php scripts and reduce website/server load.


Thanksfully XCache is shipped by default with all Debians (Etch /Lenny / Squeeze / Wheezy)  Linuces so to install it just run the standard apt cmd:

apt-get install –yes php5-xcache

Then to enable XCache all I had to do is edit /etc/php5/apache2/php.ini and place below code

debian-server:~# vim /etc/php5/apache2/php.ini


;; install as zend extension (recommended), normally "$extension_dir/"
;;zend_extension = /usr/lib/php5/20100525/


xcache.admin.enable_auth = On
; Configure this to use admin pages
; xcache.admin.user = "mOo"
; xcache.admin.pass = md5($your_password)
; xcache.admin.pass = ""

; ini only settings, all the values here is default unless explained

; select low level shm/allocator scheme implemenation
xcache.shm_scheme =        "mmap"
; to disable: xcache.size=0
; to enable : xcache.size=64M etc (any size > 0) and your system mmap allows
xcache.size  =                16M
; set to cpu count (cat /proc/cpuinfo |grep -c processor)
xcache.count =                 1
; just a hash hints, you can always store count(items) > slots
xcache.slots =                8K
; ttl of the cache item, 0=forever
xcache.ttl   =                 0
; interval of gc scanning expired items, 0=no scan, other values is in seconds
xcache.gc_interval =           0
; same as aboves but for variable cache

Note that Debian location which instructs xcache to load in Apache as a module is xcache.ini – e.g. /usr/share/php5/xcache/xcache.ini, so instead of placing above configuration right into php.ini you might prefer to place it in xcache.ini (though I personally prefer php.ini) because it is easier for me to later control how PHP behaves from single location.

To test whether XCache is enabled for Apache Webserver:

Create phpinfo.php somewhere in DocumentRoot (in my case this was /var/www/php_info.php)

debian-server:~# vim /var/www/php_info.php



When you access the php_info.php in browser you will get XCache loaded as in below screenshot:



To Test whether Xcache is enabled also for PHP CLI (applications set to run as a crontab – cronjob) :

debian-server:~# php -v
PHP 5.4.37-1~dotdeb.0 (cli) (built: Feb  2 2015 05:03:00)
Copyright (c) 1997-2014 The PHP Group
Zend Engine v2.4.0, Copyright (c) 1998-2014 Zend Technologies
    with XCache v3.2.0, Copyright (c) 2005-2014, by mOo
    with XCache Cacher v3.2.0, Copyright (c) 2005-2014, by mOo


Once it is tested as successful install you might want to enable the XCache admin (which is disabled by default), to enable XCache Admin on Debian you need to generate new password for it first like so:


echo -n "xcache_rulez" | md5sum


Then you need to add in /etc/php5/mods-available/xcache.ini

debian-server:~# vim /etc/php5/mods-available/xcache.ini
xcache.admin.enable_auth = On
; Configure this to use admin pages
 xcache.admin.user = "admin"
; xcache.admin.pass = md5($your_password)
 xcache.admin.pass = "change_with_above_generated_password_here"


To enable admin and be able to access it in a browser (if you're using as a documentroot /var/www/ and docroot supports interpretting php scripts and (has AllowOverride All) enabled to also support htaccess authentication do:

debian-server:~# cd /var/www/
debian-server:~# ln -sf /usr/share/xcache/htdocs/ xcache

When you access you should see in browser some statistics along with all configured xcache options:


If you have time you can play with the options and get some speed minor speed improvements. The overall increase in page opening XCache should give you is between 100% – 190% !

Enjoy 🙂

How much memory users uses in GNU / Linux and FreeBSD – Commands and Scripts to find user memory usage on Linux

Tuesday, February 17th, 2015




If you have to administrate a heterogenous network with Linux and FreeBSD or other UNIX like OSes you should sooner or later need for scripting purposes to have a way to list how much memory separate users take up on your system. Listing memory usage per user is very helpful for admins who manager free-shells or for companies where you have developers, developing software directly on the server via ssh. Being able to check which process eats up most memory is essential for every UNIX / Linux sysadmin, because often we as admins setup (daemons) on servers and we forgot about their existence, just to remember they exist 2 years later and see the server is crashing because of memory exhaustion. Tracking server bottlenecks where RAM memory and Swapping is the bottleneck is among the main swiss amry knives of admins. Checking which user occupies all server memory is among the routine tasks we're forced to do as admins, but because nowdays servers have a lot of memory and we put on servers often much more memory than ever will be used many admins forget to routinely track users / daemons memory consumption or even many probably doesn't know how.  Probably all are aware of the easiest wy to get list of all users memory in console non interactively with free command, e.g.:

free -m
             total       used       free     shared    buffers     cached
Mem:         32236      26226       6010          0        983       8430
-/+ buffers/cache:      16812      15424
Swap:        62959        234      62725


but unfortunately free command only shows overall situation with memory and doesn't divide memory usage by user

Thus probably to track memory users the only known way for most pepole is to (interactively) use good old top command or if you like modern (colorful) visualization with htop:

debian:~# top



Once top runs interactive press 'm' to get ordered list of processes which occupy most system memory on Linux server.Top process use status statistics will refresh by default every '3.0' seconds to change that behavior to '1' second press  s and type '1.0'. To get Sort by Memory Use in htop also press 'm'

[root@mail-server ~]# htop



However if you need to be involved in scripting and setting as a cron job tasks to be performed in case if high memroy consumption by a service you will need to use few lines of code. Below are few examples on how Linux user memory usage can be shown with ps cmd.

Probably the most universal way to see memory usage by users on Debian / Ubuntu / CentOS / RHEL and BSDs (FreeBSD / NetBSD) is with below one liner:


server:~# ps hax -o rss,user | awk '{a[$2]+=$1;}END{for(i in a)print i” “int(a[i]/1024+0.5);}' | sort -rnk2
daemon 0
debian-tor 63
dnscache 1
dnslog 0
hipo 21
messagebus 1
mysql 268
ntp 2
privoxy 1
proftpd 1
qmaill 0
qmailq 0
qmailr 0
qmails 0
qscand 291
root 94
shellinabox 1
snmp 1
statd 1
vpopmail 80
www-data 6765


Output is in MBs

Below is output from machine where this blog is running, the system runs ( Apache + PHP + MySQL Webserver + Qmail Mail server and Tor) on Debian GNU / Linux.

 To get more human readable (but obscure to type – useful for scripting) output list of which user takes how much memory use on deb / rpm etc. based Linux :


server:~# echo "USER                 RSS      PROCS" ; echo "——————– ——– —–" ; \
ps hax -o rss,user | awk '{rss[$2]+=$1;procs[$2]+=1;}END{for(user in rss) printf “%-20s %8.0f %5.0f\n”, user, rss[user]/1024, procs[user];}' | sort -rnk2


USER                 RSS      PROCS
——————– ——– —–
www-data                 6918   100
qscand                    291     2
mysql                     273     1
root                       95   120
vpopmail                   81     4
debian-tor                 63     1
hipo                       21    15
ntp                         2     1
statd                       1     1
snmp                        1     1
shellinabox                 1     2
proftpd                     1     1
privoxy                     1     1
messagebus                  1     1
dnscache                    1     1
qmails                      0     2
qmailr                      0     1
qmailq                      0     2
qmaill                      0     4
dnslog                      0     1
daemon                      0     2


It is possible to get the list of memory usage listed in percentage proportion, with a tiny for bash loop and some awk + process list command

TOTAL=$(free | awk '/Mem:/ { print $2 }')
for USER in $(ps haux | awk '{print $1}' | sort -u)
    ps hux -U $USER | awk -v user=$USER -v total=$TOTAL '{ sum += $6 } END { printf "%s %.2f\n", user, sum / total * 100; }'

107 1.34
115 2.10
119 1.34
daemon 1.32
dnscache 1.34
dnslog 1.32
hipo 1.59
mysql 4.79
ntp 1.34
privoxy 1.33
proftpd 1.32
qmaill 1.33
qmailq 1.33
qmailr 1.32
qmails 1.33
qscand 4.98
root 1.33
snmp 1.33
statd 1.33
vpopmail 2.35
www-data 86.48

Also a raw script which can be easily extended to give you some custom information on memory use by user is here.
You can also want to debug further how much memory a certain users (lets say user mysql and my username hipo) is allocating, this can easily be achieved ps like so:

root@pcfreak:~# ps -o size,pid,user,command -u mysql –sort -size
796924 14857 mysql   /usr/sbin/mysqld –basedir=/usr –datadir=/var/lib/mysql –plugin-dir=/usr/lib/mysql/plugin –user=mysql –pid-file=/var/run/mysqld/ –socket=/var/run/mysqld/mysqld.sock –port=3306


root@pcfreak~# ps -o size,pid,user,command -u hipo –sort -size|less
13408 19063 hipo     irssi
 3168 19020 hipo     SCREEN
 2940  2490 hipo     -bash
 1844 19021 hipo     /bin/bash
 1844 19028 hipo     /bin/bash
 1844 19035 hipo     /bin/bash
 1844 19042 hipo     /bin/bash
 1844 19491 hipo     /bin/bash
 1844 22952 hipo     /bin/bash
  744  2487 hipo     sshd: hipo@pts/0
  744  2516 hipo     sshd: hipo@notty
  524  2519 hipo     screen -r
  412  2518 hipo     /usr/lib/openssh/sftp-server

You see from below output user running with www-data (this is Apache Webserver user in Debian) is eating 86.48% of overall system memory and MySQL server user is using only 4.79% of available memory

Output is shown in Megabytes per username memory usage, and user memory usage is ordered (stepping-down / descentive) from top to bottom

Getting more thoroughful and easier to read reporting without beeing a 31337 bash coder you can install and use on Linux smem – memory reporting tool .

SMEM can provide you with following memory info:

  • system overview listing
  • listings by process, mapping, user
  • filtering by process, mapping, or user
  • configurable columns from multiple data sources
  • configurable output units and percentages
  • configurable headers and totals
  • reading live data from /proc
  • reading data snapshots from directory mirrors or compressed tarballs
  • lightweight capture tool for embedded systems
  • built-in chart generation

Installing smem on Debian 6 / 7 / Ubuntu 14.04 / Turnkey Linux etc. servers is done with standard:


debian:~# apt-get install –yes smem



To install smem on CentOS 6 / 7:


[root@centos ~ ]# yum -y install smem

On Slackware and other Linux-es where smem is not available as a package you can install it easily from binary archive with:


cd /tmp/
tar xvf smem-1.3.tar.gz
sudo cp /tmp/smem-1.3/smem /usr/local/bin/
sudo chmod +x /usr/local/bin/smem


Two most common smem uses are:


root@mail:~# smem -u
User     Count     Swap      USS      PSS      RSS
dnslog       1       44       48       54      148
qmaill       4      232      124      145      464
hipo        11    13552     8596     9171    13160
qscand       2     4500   295336   295602   297508
root       188   217312  4521080  4568699  7712776


Below command shows (-u – Report memory usage by user, -t – show totals, -k – show unix suffixes)

root@mail:~# smem -u -t -k
User     Count     Swap      USS      PSS      RSS
dnslog       1    44.0K    48.0K    54.0K   148.0K
qmaill       4   232.0K   124.0K   145.0K   464.0K
hipo        11    13.2M     8.4M     9.0M    12.9M
qscand       2     4.4M   288.4M   288.7M   290.5M
root       188   212.2M     4.3G     4.4G     7.4G
           206   230.1M     4.6G     4.6G     7.7G

To get users memory use by percentage with smem:

root@mail:~# smem -u -p
User     Count     Swap      USS      PSS      RSS
dnslog       1    0.00%    0.00%    0.00%    0.00%
qmaill       4    0.00%    0.00%    0.00%    0.01%
hipo        11    0.17%    0.11%    0.11%    0.16%
qscand       2    0.05%    3.63%    3.63%    3.66%
root       194    2.64%   56.18%   56.77%   95.56%

It is also useful sometimes when you want to debug system overloads caused by external hardware drivers loaded into kernel causing issues to get list of system wide memory use sorted by user


 root@mail:~# smem -w -p
Area                           Used      Cache   Noncache
firmware/hardware             0.00%      0.00%      0.00%
kernel image                  0.00%      0.00%      0.00%
kernel dynamic memory        38.30%     36.01%      2.28%
userspace memory             60.50%      0.98%     59.53%
free memory                   1.20%      1.20%      0.00%

smem is very nice as if you're running it on a Desktop Linux system with Xserver installed you can see also graphical output of memory use by application:

root@desktop-pc:~# smem –bar pid -c "pss uss"


smem can even generate graphical pie charts to visualize better memory use

root@desktop-pc:~# smem -P '^k' –pie=name



If there is a high percentage shown in firmware/hardware this means some buggy module is loaded in kernel eating up memory, to fix it debug further and remove the problematic module.
userspace memory actually shows the percantage of memory out of all server available RAM that is being consumed by applications (non kernel and other system processes which make the system move). You see in above example the kernel itself is consuming about 40% of system overall available memory. 

We all know the SWAP field stands for hard disk drive used as a memory when system is out, but there are 3 fields which smem will report which will be probably unclear for most here is also explanation on what USS / PSS / RSS means?

RSS is the Resident Set Size and is used to show how much memory is allocated to that process and is in RAM. It does not include memory that is swapped out. It does include memory from shared libraries as long as the pages from those libraries are actually in memory. It does include all stack and heap memory too.

There is also PSS (proportional set size). This is a newer measure which tracks the shared memory as a proportion used by the current process. So if there were two processes using the same shared library from before.

USS stands for Unique set size, USS is just the unshared page count, i.e. memory returned when process is killed 

PSS = Proportional set size, (PSS),  is a more meaningful representation of the amount of memory used by libraries and applications in a virtual memory system.  
Because large portions of physical memory are typically shared among multiple applications, the standard measure of memory usage known as resident set size (RSS) will significantly overestimate memory usage. The parameter PSS instead measures each application’s “fair share” of each shared area to give a realistic measure. For most admins checking out the output from RSS (output) should be enough, it will indicate which user and therefore which daemon is eating up all your memory and will help you to catch problematic services which are cause your server to run out of RAM and start swapping to disk.

The feast of 26 Zographou Bulgarian Holy Mount Athos Martyrs – burned alive by the Roman Catholic Crusaders

Friday, October 24th, 2014


On 23 October (10 of October in Julian Calendar every year in Zograph Monastery in Holy Mount Athos is celebrated the martyrdom of the 26 Martyrs who were martyed by Latin crusaders in October 10, 1280. The 26 martyrs were burned alive after refusal to accept Union with the Roman Catholic Church as ordered by Byzantine emperor Michael VIII Paleologos. The then wanting to secure his throne emperor gave allowance for Crusaders together with his mercenaries Tatars and and Turks to go and “convert” the Orthodox Slavs to accept the union with the pope who wanted a primacy in the Church.

Mt. Athos stood in firm opposition to the Union. The Athonite monks sent a letter to Michael pointing out that the primacy of the Pope, his commemoration in the churches, celebrating the Eucharist with unleavened bread, the insertion of the “filioque” [“and from the Son”] into the Creed, could not be accepted by Orthodox, and they asked the emperor to change his mind. “We clearly see,” the letter said, “that you are becoming a heretic, but we implore you to forsake all this and abide in the teachings that were handed down to you…. Reject the unholy and novel teachings of a false knowledge, speculations, and additions to the Faith.”

Holy Theotokos – The Virgin Mary icon which spoke with a human voice to a Zographou monk

An icon spoke to an old monk warning that the “enemies of Christ” are coming. The monk went to forewarn the brothers (as he was living 30 minutes afar in a grave-yard), but for his surprise the Holy icon of the Theotokos which spoke to him was found on the monastic entrance.
The brother went and told the abbot (Igumen) Thomas who told to the brothers to either flew in the woods if they’re weak in spirit and to the strong he said to stay and cofess the Holy Orthodox faith. Abbot Thomas together with the 23 monks (24 monks including the abbot) toghet with 4 pilgrims decided to stay in the monastery and suffered martyrdom. The Crusaders who were returning from Jerusalem sent by the ungodly emperor tried to convince the 26 confessors to accept Roman Catholic doctrines such as “filioque” (The teaching that the Holy Spirit cames also from the Son) and to celebrate the eucharist with unleavened bread (like the Jewish) and wanted the confessors to accept the papal union accepted also by the emeror Michael. The 26 Martyrs rebuked these heresies and explained that the “filique” is against the decisions of the 7 Church Councils. Also they give the proof that the Holy Spirit doesn’t proceed from the Son by retelling how John The Baptist baptized Christ and how the Holy Spirit descent over the Lord Jesus Christ in form of a dove. This didn’t convince the papists and the truthful words of the Zographus monks rebuked their error the papists were angered and burned the tower with the holy Martyrs alive. One of the monks fall of the burning tower and the latin though he is dead left him behind however he survived more 30 days! – even though he was on a dying bed and later told what happened to the brothers which came from their hiding places to the monastery. The Holy Martyrs prayed from the fire their last prayer to God to save the Holy Mount Athos and every true Christian on earth from heresies. When they ended their prayer they heard a voice from heaven “Rejoice for great is your reward in heaven!”. The Roman Crusaders heard the voice and were scared howeveras their spiritual eyes were darkened by the lack of the Grace of the Holy Spirit, they kept in their heart tightening. The Martyrdom happened according to Greek chronicles on 10 of October 1280.

The names of the Martyrs for Christ were as follows:

Igumen Thomas, and the monks Barsanuphius, Cyril, Michael, Simon, Hilarion, James, Job, Cyprian, Sava, Jacob, Martinian, Cosmas, Sergius, Menas, Joasaph, Joannicius, Paul, Anthony, Euthymius, Dometian, Parthenius, and four laymen.

The tower building where the holy martyrs were burned was partially kept even though the fire until 1874 however the tower was already too old and it was about to ruin – that’s why it hadto be destroyed. To preserve the memory about the martyrdom of 26 martyrs all brothers of the Zographou monastry decided in one spirit to build on its place a monument.


This happened the same year 1873. The monument had to be sanctified on the day when the memory of the martyrs is celebrated at the eve after sunrise began a night vigil. The night was moonless and on the heaven one could see only few stars. All around was silence. During the vigil exactly in midnight, after beginning the living and martyrdom of the the holy Zographos martyrs”, above the church all 600 hundred people saw a fire column. Column lighted up the whole monastery and the whole region with such a bright light, that even the small objects in the monastery could be seen. This divine column stayed over the Church for 3-4 minutes and moved and stayed above the monument for 3-4 minutes more and after that started ascending above and formed a ring like a crown, crowning the place where the holy martyrs suffered.

burning-of-26-bulgarian-martyrs-on-holy-mount-athos-zographou-monastery-by-the-crusaders roman catholiclatins

This unusual event continued for about 15 minutes. An eyesights of the miracle were all the brotherhood, guests and hermits who came from nearby Sketes for the feast.

That’s how the Almight God has shown by this miracle omen showing in front of everybody how Godly was the martyrdom of this great confessors of the true faith and loyalty to the Holy Orthodox Church.

Holy 26 Martyrs and Cofessors of the true faith pray the Lord Jesus Christ to save our souls!

Shutdown tomcat server node in case of memory depletion – Avoiding Tomcat Out of memory

Friday, June 6th, 2014


Out Of Memory Errors, or OOMEs, are one of the most common problems faced by Apache Tomcat users. Tomcat cluster behind Apache unreachable (causing customer downtimes). OOME errors occur on production servers that are experiencing an unusually high spike of traffic.

Out of memory errors are usually a problem of application and not of Tomcat server. OMEs have become such a persistent topic of discussion in the Apache Tomcat community cause its so difficult to trace to their root cause. Usually 'incorrect' web app code causing Tomcat to run out of memory is usually technically correct.

Most common reasons for Out of Memory errors in application code are:

  •     the heap size being too small
  •     running out of file descriptors
  •     more open threads than the host OS allows
  •     code with high amounts of recursion
  •     code that loads a very large file into memory
  •     code that retaining references to objects or classloaders
  •     a large number of web apps and a small PermGen

The following java option -XX:OnOutOfMemoryError= could be added to any of tomcat java application servers in in  JAVA_OPTS= variable in case of regular Out of Memory errors occur making an application unstable.


Where < path_to > is shutdown script(which performs kill <tomcat_pid> if normal shutdown fails) for the tomcat instance.

With this setup if any tomcat instance run out of memory it will be shutdown (shutdown script invoked) – as result the Apache proxy infront of Tomcats should not pass any further requests to this instance and application will visualize / work properly for end customers.

Usually a to invoke in case of OOM would initiate a Tomcat server restart something like:

for i in `ps -ef |grep tomcat |grep /my_path_to_my_instance | awk '{print $2}'`
kill -9 "$i"
#path and script to start tomcat

To prevent blank pages returned to customer because of starting stopping Tomcat you can set in Reverse Apache Proxy something like:

<Proxy balancer://mycluster>
   BalancerMember ajp:// route=delivery1 timeout=30 retry=1
   BalancerMember ajp:// route=delivery2 timeout=30 retry=1

Where in above example I assume, there are only two tomcat nodes, for more just add respective ones.

Note that if the deployed application along all servers is having some code making it crash all tomcat nodes can get shutdown all time and you can get in a client havoc 🙂

Thomas Sunday – The day of Disbelievers

Monday, April 28th, 2014


A week passed since we Christian celebrated Resurrection of Christ (Pascha). Each year on first Sunday after Easter in orthodox Church is celebrated the so called Thomas Sunday. So why is it called Thomas Sunday and why it is the day of disbelievers?
The root of this ancient Christian feast comes after commemoration of Christ desciple St. Thomas who disbelieved the testimony of ( 10 apostles ) and the Virgin Mary  that Jesus Christ is Risen from the Death.

The disbelieve of Thomas was logical and human cause even though Thomas was with the Apostles with Christ for 3 years, saw all Jesus miracles and shared the Secret Supper (Last Supper), and even knew in advance (heard by Jesus on Last supper) that Jesus will betrayed mocked, hanged on the Cross and Rise from the death on the third day, he disbelieved.

Thomas Sunday (Sundy of Thomas) is "the day of Disbelievers", because all are disbelievers in moments of their life not only those who believe God but all the humanity!  Even the most faithful Christian, be it a deacon, monk or priest has difficult moments in life where God's existence or providence for one's faith is seriously questioned.
The fallen nature of man is such that the initial belief in God given to man in Eden (Paradise garden) is broken, and only in Jesus's name through the Gift of Faith given by the Holy Spirit, believe in God is restored.

Thomas very much like unto everyone of us doubted the rumors of Christ resurrection and said he would only believe in Resurrected Christ only if he sees his hands nails print and put his fingers into Christ’s wounds to test he is not seeing a Ghost but Christ is alive in a body after his death.

Here is the Gospel reading re-telling the story in short:

“Then the same day at evening, being the first day of the week, when the doors were shut where the disciples were assembled for fear of the Jews, came Jesus and stood in the midst, and saith unto them, Peace be unto you.” (John 20:19)

“But Thomas, one of the twelve, called Didymus, was not with them when Jesus came. The other disciples therefore said unto him, We have seen the Lord. But he said unto them, Except I shall see in his hands the print of the nails, and put my finger into the print of the nails, and thrust my hand into his side, I will not believe.” (John 20:24-26)

And after eight days again his disciples were within, and Thomas with them: then came Jesus, the doors being shut, and stood in the midst, and said, Peace be unto you.
Then he said to Thomas, “Put your finger here; see my hands. Reach out your hand and put it into my side. Stop doubting and believe.”
Thomas said to him, “My Lord and my God!”
Then Jesus told him, “Because you have seen me, you have believed; blessed are those who have not seen and yet have believed.”
Jesus did many other miraculous signs in the presence of his disciples, which are not recorded in this book.
But these are written that you may believe that Jesus is the Christ, the Son of God, and that by believing you may have life in his name.” (John 20:31)

We Christians should be joyful for have not seen Christ in Flesh but have believed for we are blessed for his believe without seeing.

By same faith in God without seeing him even in old times the Jews were led by the Lord God in the desert have won wars by their believing without seeing God, prophets has prophecised, Simeon (The God receiver) hold The Savior (Christ) in his hands, by faith David won the battle with Goliath, by faith we understand the universe was formed at God’s command, by faith we know that the visible came out of the invisible.

o Kyrios mou kai o Theos mou (Greek) – My Lord and my God (Jn. 20:28) this declaration of faith clearly shows an unexpressable excitement of Thomas and his unexpectency to see Christ resurrected. Here it is interesting that here the son of God Jesus Christ is called by Thomas exactly how Jewish used to call God Yahweh (One and Only God) in the Old testament.

Today the evangical story is very accurate for our generation – a generation of disbelievers, even we who say we believe often doesn’t justify our believe with our deeds, we say we believe but we don’t keep God’s commandment “to love God and our neigbor like ourselves.” Often only difference between believers and disbelievers is on Sunday we believers visit Church and “play Christians”, but even but in daily life our deeds are same like unbelievers. Often many are disbelievers not because they reject God but because they never heard the Gospel or misheard it, also we disbelieve because we’re very much like st. Thomas, we often say “I will believe in God if I see him”, but even Thomas who saw God before the Crucifix and knew him disbelieved – a proof that often seing once could still leave space for doubt. The glorious event of Christ showing himself Alive to Thomas was made by Christ to establish the Church and strengthen faith of first Christians in resurrection. Nowadays there are plenty of people who question God’s existence saying that they will believe if they see but they’re not given to see the resurrected Christ because God knows that even if we see the Lord Jesus Christ resurrected we would try to rationally explain the phenomenon with holograms, modern technology or science.

Thomas Sunday is not only a day of Thomas disbelieve it is a day of disbelieve of all humanity. , St. Thomas should be an example even to all of us Christian disbelievers and non-believers that even if we disbelieve and doubt and strive to see God, He is powerful to come and appear Resurrected in His Glory to our souls.
Let us therefore have the Wisdom of the Holy Apostles and say together with them “Lord, Increase our faith.” Luke 17:5

How to download books from Books Google with Google Book Download stand alone program and Greasemonkey with Google Books Downloader script

Thursday, February 7th, 2013

If you are student or just a researcher, you already know most of the good books you can find are on Google Books's is nice, but not all browsers support it well. Older mobile phones has big troubles with it, plus it is always nice to have a stored copy of book on your PC for later review or just to refresh your memory on books previously read.

Thus if you get to task to download Books from Google a quick research reveals few programs claiming to support downloading Books from Google in PDF;

1. Google Books Download standalone application for Windows and Mac OS X

Google Books Download is said to support Save of Google books in PDF, JPEG or PNG format.
This program works good whether you need to extract only certain book pages, however with complete books it often hangs. Other problem is it is  proprietary software, (freeware), so pages book pages it downloads in PDF had a big red color stamp complaining the program is trial.
There is a cracked version available on's website. But as Piratebay is filtered from here. To test it I had to google it via piratebay proxy: –  with "piratebay  google books download"

Google Books Download
, standalone app from Piratebay is at current version 3.1.308.
As you can see from screenshot Google Book Download has two modes of work, one is;
Download Manually
– This is used for manual download a pages from a complete book and converting them to PDF.
Download Automatically – Is purposed to download a complete book from and converting it to PDF. Downloading a complete copy of book using this mode is sometimes, hanging, plus it is really, really slow. The reason is each of the pages from the Book is first scanned using OCR (Optical Character Recognition) technology page by page and later after all pages are downloaded in pictures, they're converted to 1 PDF file.

Because Download Automatically loops at certain pages, this makes Google Books Download almost useless for people looking to store a full copy of books on ….

2. Downloading PDFs from with Firefox Greasemonkey and Google Book Downloaderjavascript

a. Install GreaseMonkey Firefox add-on

If you never before heard of Greasemonkey is a Mozilla Firefox Extension that allows users to install scripts that make on-the-fly changes to web page content after or before the page is loaded in the browser (also known as augmented browsing).

b. Install Google book downloader GreaseMonkey javascript

After a FF restart, you're ready to download any book from
To use it open the book you want to download and on the left upper corner you will see a Download this book button, press it and the book will be scanned in OCR and saved in PNG picture format. Below is a screenshot showing a sample book to download from;

how to download book from google in firefox web browser screenshot

After each book page is succesfully download in page on the left pane you get a download status;

google book download firefox screenshot pictures - Scythian Monks download - how to download books to pictures from Google books on Windows XP, Windows 8

You should keep in mind that the download links of Google Book pages, will have a time expiry, so if you don't hurry up to save the pictures for later use soon links will become inaccessible and showing as broken from Google – I'm not sure how much exactly is google's max expiry time set of links but I guess it should be something 5-10 mins.

The pages of PDF, gets fetched as pictures one by one so it takes 20 secs or so to get all links to pages. Since Google Books Downloader only provides links to PDF pages it is necessery to either save each of the pictures manually (quite a lot of effort) or Install and use lets say DownThemAll! FF download extension. Using DownThemAll does not completely automates picture downloads, as you need to manually select all pictures for downloading, but at least selecting pages saves some time. To download all book pages with DownThemAll click with right mouse button on the left pane where links to pictures appears and choose download with DownThemAll!. After that tick on all links pointing to……. to make them have the green tick as shown in below screenshot;

Once you have all PNGs saved on the PC you need to then convert them to unified PDF file. One way to do this is using ImageMagick's convert command line tool.
To do so install imagemagick for Windows downloading Win binaries from here
There are a bunch of binaries you will need to install named like ImageMagick-*-x86-static.exe

Run cmd.exe, change dir (cd) to folder where the just download book is saved in PNG and issue:

C:\Downloads> convert *.png pdf/my-book-from-pictures.pdf

How to speed up Linux Flash Player videos in Firefox on old Computers

Wednesday, January 30th, 2013

Firefox browser cache variables to tune for better Flash player performance Linux screenshot

If you happen to run old Computer hardware with lets say 256 or 512 MB of memory, a CPU of 600-800Mhz and a small hard disk like 5 / 10 GB and you need to have Flash Player on Firefox play Videos in Youtube and Vimeo with as less obstructions as possible, it is useful to take a look and try tuning up browser caching values, to do so type in URL Address Bar


iceweasel about:config Iceweasel Firefox about:config screenshot in URL address bar

Then search for;


Iceweasel Firefox browser cache screenshot Debian Gnu Linux screenshot tiny

Raise (tune up) the values for:

browser.cache.disk.capacity 1048576

Try to raise this value with 50% (524288), (1048576 + 524288) = 1572864.

By default, as you see

browser.cache.disk.enable is set to false

Try to change it to true, as this might have positive effect on flash video buffering and thus improve a bit experience.

browser.cache.disk.smart_size_cached_value 358318

Again it is good practice to try raise it with 50% and test if Flash Player performs better. I.e. (358318/2) = 179159, (358318+179159) = 537477. Hence raise it too lets say 358318. I give the 50%, example because the cache size on Firefox (IceWeasel) will differ depending on the browser version Linux distro and architecture.

There are few other caching, variables to tune, though I doubt if they will have impact on Flash Player performance it is good to know they're there. To see all Mozilla caching variables in Search filed, type "cache". One other non Flash Player performance related variable to check and tune is:


In time of writting on my Firefox ver. 18.0.1 it is set to 5242880.
I'm looking forward to hear if this little tuning tips helped improve Flash Player. If you happen to have some positive impact on Video flow, please drop a comment with Linux distribution type and version, Flash Player version and changed caching variables.
Hope this little post helps. Happy tuning 🙂