Archive for the ‘Performance Tuning’ Category

Remove pre-installed HP, Dell, Asus, Acer, Toshiba not needed default vendor software on a new bought PC notebook quickly with Decrap My Computer

Thursday, April 14th, 2016

While browsing today and looking for software to clean up all the spy software from my corporate HP laptop, I've come across an interesting tool called Decrap which aims at removing Bloatware from a Windows PC / notebook

So what is Bloatware ?

The term Bloatware (also called jokingly crapware) is term is the one that was coined to describe, the default pre-installed software that comes to you together with Windows pre-installed OS by the hardware manufacturer.
I'm sure anyone who bought brand new branded PC or laptop over the last 10 years have already suffered the unwanted and unnecessery
bunch of software that comes pre-installed freeware programs aiming to help you in your daily work but in reality just slowing down your PC
and showing annoying popups or at best keeping useless in Windows system apptray.

Let me give you an example:

Cleanup (Remove) common ASUS, HP, Dell default  installed unneded (Bloatware) software

Many users may want to uninstall ASUS Crapware software such as ASUS Tutor, ASUS LifeFrame3, ASUS WebStorage and ASUSVibe.

Like Asus, HP computers often come preloaded with useless software from factory, example for this is HP Customer Service enhancements, HP Update, HP Total Care Setup and ProtectSmart.

If you buy Dell PC notebook soon you'll discover that there are several preloaded software (often unnecessery software) such as Dell Stage, Dell Digital Delivery and Dell DataSafe.

Toshiba computers and notebooks contain pre-loeaded "crapware" software from Toshiba.
Just to mention a few of those: Toshiba Disc Creator, Toshiba ReelTime, Service Station, Bulletin Board and Toshiba Assist.

Often there are fingerprint reader programs, Wi-Fi connection managers, Bluetooth managers, Audio Management sofware and other third party vendor software which tend to be not working as good as others softwares from third vendor, so Decrap is to help you to identify and remove these too in a easy GUI manner.

Non-experienced Computer users often leave the bloatware to hang around for even years and only if some relative that is an IT involved person / sysadmin / Even once you're aware that the Bloatware is on the system the ordinary user is hard to remove it as he is scared not to break the system.
Besides that fften this bloatware just soft comes so much integrated into Windows that removing it costs hours of tries and research online on
all the Bloatware components and even then could mislead you so you break the PC. programmer etc. comes home of such users finds out about the happily existing of the useless software on the notebook.

So here is Decrap My Computer coming at place aiming to help to remove the unnecessery Hardware vendor software in few easy (Click, Click, Click Next ..) steps.


Then decrap does silently all the complex operations and suggestions to make the HP, Dell, Asus, Toshiba manufacturer prebundled software to be stopped and uninstalled.
Decrap My Computer is a freeware, lightweight and easy to use and lets you safely remove crapware and bloatware, or any software, from any Windows PC.

Even for Old computers, Decrap comes handy for the unexperienced avarage user who used his laptop with this useless  default vendors programs silently killing the performance respectively user experience for years.

Using Decrap is quite intuitive PC is scanned for Bloatware and then after a backup Windows Restore Point is offered you're offered to review and Uninstall the unwanted softwares. There is also an automatic mode but those one still could be a bit dangerous, so use the automatic mode only on multiple machines with the same model  / brand notebooks that comes prebundled with same sofware after testing and confirming the automatic mode on 1 initial machine will not break up some needed functionality.


Here is few screenshots of the tool in action:



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Migrate Webserver and SQL data from old SATA Hard drive to SSD to boost websites performance / Installing new SSD KINGSTON 120GB hard disk on Linux

Monday, March 28th, 2016

Blog and websites hosted on a server were giving bad performance lately and the old SATA Hard Disk on the Lenovo Edge server seemed to be overloaded from In/Out operations and thus slowing down the websites opeining time as well as SQL queries (especially the ones from Related Posts WordPress plugin was quite slow. Sometimes my blog site opening times were up to 8-10 seconds.

To deal with the issue I obviously needed a better speed of I/O of hard drive thus as I've never used SSD hard drives so far,  I decided to buy a new SSD (Solid State Drive) KINGSTON SV300S37A120G, 605ABBF2, max UDMA/133  hard disk.
Mounting the hard disk physically on the computer tower case wasn't a big deal as there are no rotating elements of the SSD it doesn't really matter how it is mounted main thing is that it is being hooked up somewhere to the case.

I was not sure whether the SSD HDD is supported by my Debian GNU / Linux so I had see whether Linux Operating System has properly detected your hard disk use dmesg

1. Check if SSD Hard drive is supported in Linux


linux:~# dmesg|grep -i kingston
[    1.182734] ata5.00: ATA-8: KINGSTON SV300S37A120G, 605ABBF2, max UDMA/133
[    1.203825] scsi 4:0:0:0: Direct-Access     ATA      KINGSTON SV300S3 605A PQ: 0 ANSI: 5


linux:~# dmesg|grep -i sdb
[    1.207819] sd 4:0:0:0: [sdb] 234441648 512-byte logical blocks: (120 GB/111 GiB)
[    1.207847] sd 4:0:0:0: [sdb] Write Protect is off
[    1.207848] sd 4:0:0:0: [sdb] Mode Sense: 00 3a 00 00
[    1.207860] sd 4:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[    1.207928]  sdb: unknown partition table
[    1.208319] sd 4:0:0:0: [sdb] Attached SCSI disk


Well great news as you see from above output obviously the Kingston SSD HDD was detected by the kernel.
I've also inspected whether the proper dimensions of hard drive (all 120 Gigabytes are being detected by the OS):


linux:~# fdisk -l /dev/sdb
Disk /dev/sdb: 120.0 GB, 120034123776 bytes
255 heads, 63 sectors/track, 14593 cylinders, total 234441648 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Even better as the proper HDD sizing was detected by Linux kernel.
Next thing to do was of course to create ext4 filesystem on the SSD HDD.
I wanted to give 2 separate partitions for my Webserver Websites DocumentRoot directories which all lay under the standard Apache location inside /var/www as well as MySQL data folder which is also under the standard Debian based Linuces – /var/lib/mysql as the SQL data directory was just 3.3 GB size, I've decided to reserve 20GB gigabytes for the MySQL and another 100 GB for my PHP / CSS / JS / HTML and other data files /var/www.

2. Create SSD partitions with cfdisk

Hence I needed to create:

1. SSD partition of 100GB
2. SSD partition of 20GB

I have cfdisk installed and I believe, the easiest way to create the partitions is using interactive partitioner as CFDISK instead of fdisk: so in order to make the proper partitions I've ran


linux:~# cfdisk /dev/sdb

I' will skip explainig details on how to use CFDISK as it is pretty standard – display or manipulate disk partition table tool.
Just press on NEW button (moving with arrow keys buttons) and choose the 2 partitions size 100000 and 20000 MB (one thing to note here is that you have to choose between Primary and  Logical creation of partitions, as my SSD is a secondary drive and I already have a ) and then press the
WRITE button to save all the partition changes.

!!! Be very careful here as you might break up your other disks data make sure you're really modifying the SSD Hard Drive and not your other /dev/sda or other attached external Hard drive or ATA / SATA disk.
Press the WRITE button only once you're absolutely sure, you do it at your own (always create backup of your other data and don't blame me if something goes wrong) …

Once created the two partitions will look like in the screenshot below:


3. Create ext4 filesystem 100 and 20 GB partitions

Next thing to do before the two partitions are ready to mount under Webserver's files documentroot /var/www and /var/lib/mysql is to create ext4 filesystem, though some might prefer to stick to ext3 or reiserfs partition, I would recommend you use ext4 for the reason ext4 according to my quick research is said to perform much better with SSD Hard Drives.

The tool to create the ext4 filesystems is mkfs4.ext4 it is provided by debian package e2fsprogs I have it already installed on my server, if you don't have it just go on and install it with:

linux:~# apt-get install –yes e2fsprogs


To create the two ext4 partitions run:

linux:~# mkfs4.ext4 /dev/sdb5


linux:~# mfs4.ext4 /dev/sdb6

Here the EXT4 filesystem on partition that is supposed to be 100 Gigabytes will take 2, 3 minutes as the dimensions of partition are a bit bigger, so if you don't want to get boring go grab a coffee, once the partitions are ready you can evaluate whether everyhing is properly created with fdisk you should get output like the one below


linux:~# fdisk -l /dev/sdb
Disk /dev/sdb: 120.0 GB, 120034123776 bytes
255 heads, 63 sectors/track, 14593 cylinders, total 234441648 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1              63   234441647   117220792+   5  Extended
/dev/sdb5             126    39070079    19534977   83  Linux
/dev/sdb6        39070143   234441647    97685752+  83  Linux


4. Mount newly created SSD partitions under /var/www and /var/lib/mysql

Before I mounted /var/www and /var/lib/mysql in order to be able to mount under the already existing directories I had to:

1. Stop Apache and MySQL server
2. Move Mysql and Apache Documentroot and Data directories to -bak
3. Create new empty /var/www and /var/lib/mysql direcotries
4. Copy backpups ( /var/www-bak and /var/lib/mysql-bak ) to the newly mounted ext4 SSD partitions

To achieve that I had to issue following commands:

linux:~# /etc/init.d/apache2 stop
linux:~# /etc/init.d/mysql stop

linux:~# mv /var/www /var/www-bak
linux:~# mv /var/lib/mysql /var/lib/mysql-bak

linux:~# mkdir /var/www
linux:~# mkdir /var/lib/mysql
linux:~# chown -R mysql:mysql /var/lib/mysql

Then to manually mount the SSD partitions:

linux:~# mount  /dev/sdb5 /var/lib/mysql
linux:~# mount /dev/sdb6 /var/www

To check that the folders are mount into the SSD drive, ran mount cmd:


linux:~# mount
/dev/sda1 on / type ext3 (rw,errors=remount-ro)
tmpfs on /lib/init/rw type tmpfs (rw,nosuid,mode=0755)
proc on /proc type proc (rw,noexec,nosuid,nodev)
sysfs on /sys type sysfs (rw,noexec,nosuid,nodev)
udev on /dev type tmpfs (rw,mode=0755)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=620)
fusectl on /sys/fs/fuse/connections type fusectl (rw)
/dev/sdc1 on /backups type ext4 (rw)
/dev/sdb5 on /var/lib/mysql type ext4 (rw,relatime,discard,data=ordered))
/dev/sdb6 on /var/www type ext4 (rw,relatime,discard,data=ordered))


That's great now the filesystem mounts fine, however as it an SSD drive and SSD drives are being famous for having a number of limited writes on disk before the drive lifetime is over it is a good idea to increase a bit the lifetime of the SSD by mounting the SSD partitions with noatime and errors=remount-ro (in order to not log file access times to filesystem table and to remount the FS read only in case of some physical errors of the drive).

5. Configure SSD partitions to boot every time Linux reboots

Now great, the filesystems gets mounted fine so next thing to do is to make it automatically mount every time the Linux OS boots up, this on GNU / Linux is done through /etc/fstab, for my 2 ext4 partitions this is the content to add at the end of /etc/fstab:


/dev/sdb5               /var/lib/mysql      ext4        noatime,errors=remount-ro       0       1
/dev/sdb6               /var/www        ext4    noatime,errors=remount-ro       0       1


quickest way to add it without a text editor is to echo to the end of file:

linux:~# cp -rpf /etc/fstab /etc/fstab.bak_25_03_2016
linux:~# echo ' /dev/sdb5               /var/lib/mysql      ext4        noatime,errors=remount-ro,discard       0       1' >> /etc/fstab
linux:~# echo ' /dev/sdb6               /var/www        ext4    noatime,errors=remount-ro,discard       0       1 ' >> /etc/fstab

Then mount again all the filesystems including the 2 new created SSD (100 and 20 GB) partitions:

linux:~# umount /var/www
linux:~# umount /var/lib/mysql
linux:~# mount -a

To assure properly mounted with noatime and remount-ro on errors options:

linux:~# mount | grep -i sdb
/dev/sdb5 on /var/lib/mysql type ext4 (rw,noatime,errors=remount-ro)
/dev/sdb6 on /var/www type ext4 (rw,noatime,errors=remount-ro)


It is also a good idea to check a statistics of disk free command:

linux:~# df -h|grep -i sdb
/dev/sdb5         19G  0G    19G  0% /var/lib/mysql
/dev/sdb6         92G   0G    92G  0% /var/www

6. Copy all Webserver and SQL data from backupped directories to new SSD mounted

Last but not least is to copy all original content files from /var/www-bak and /var/lib/mysql-bak to the new freshly  created SSD partitions, though copying the files can be made with normal linux copy command (cp),
I personally prefer rsync because rsync is much quicker and more efficient in copying large amount of files in my case this were 48 Gigabytes.

To copy files from with rsync:


linux:~# rsync -av –log-file /var/log/backup.log  /var/www-bak /var/www
linux:~# rsync -av –log-file /var/log/backup.log  /var/lib/mysql-bak /var/lib/mysql

Then ofcourse, finally to restore my websites normal operation I had to bring up the Apache Webservers and MySQL service


linux:~# /etc/init.d/apache2 start
linux:~# /etc/init.d/mysql start

7. Optimizing SSD performance with periodic trim (discard of unused blocks on a mounted filesystem)

As I digged deeper into how to even further optimize SSD drive performance I learned about the cleaning action TRIM of the partitions for a long term performance proper operation, to understand it better think about trimming like Windows degrament operatin.

fstrim – discard unused blocks on a mounted filesystem

fstrim [-o offset] [-l length] [-m minimum-free-extent] [-v] mountpoint

fstrim is used on a mounted filesystem to discard (or "trim") blocks which are not in use by the filesystem. This is useful for
solid-state drives (SSDs) and thinly-provisioned storage.

By default, fstrim will discard all unused blocks in the filesystem. Options may be used to modify this behavior based on range or
size, as explained below.

Trimming is really necessery, otherwise SSD become very slow after some time. All modern SSD's support TRIM, but older SSD's from before 2010 usually don't.
Thus for an older SSD you'll want to check this on the website of the manufacturer.

As I mentioned earlier TRIM is not supported by all SSD drives, to check whether TRIM is supported by SSD:

linux:~# hdparm -I /dev/sdb|grep -i -E 'trim|discard'
                  *          Data set Management TRIM supported (limit 1 block)

It's easiest to let the system perform an automatic TRIM. That can be done in several ways.

The quickest way for trimming is to place into /etc/rc.local trim  commands, in my case it was the following commands:


fstrim -v /var/lib/mysql
fstrim -v /var/www

To add it I've used my favourite vim text editor.
Adding commands to rc.local will make SSD trimming be executed at boot time so this will reduce a bit the downtime during the trim with some time so perhaps for those like me which are running a crually important websites a better

An alternative way is to schedule a daily cron job to do just place a new job in /etc/cron.daily/trim e.g.:

linux:~# vim /etc/cron.daily/trim


fstrim -v /var/lib/mysql
fstrim -v /var/www

linux:~# chmod +x /etc/cron.daily/trim

However the best way to enable automatic trimming to SSD  is to just add the discard parameter to /etc/fstab I've already done that earlier in this article.

Not really surprising the increase of websites opening (page load times) were decreased dramatically web page loading waiting time fall down 2 to 2.5 times, so the moral of story for me is always when possible from now on to use SSD in order to have superb websites opening times.

To sum it up what was achieved with moving my data into SSD Drive, before moving websites and SQL data to SSD drive the websites were opening for 6 to 10 seconds now sites open in 2 to 4.5 seconds which is below 5 seconds (the normal waiting time for a user to see your website).
By the way it should be not a news forfor people that are into Search Engine Optimization but might be for some of unexperienced new Admins and Webmasters that, all that all page opening times that  exceeds 5 secs is considered to be a slow website (and therefore perhaps not worthy to read).
The high load page times >5 secs makes the website also less interesting not only for end users but also for search engines (Google / Yahoo / Bing / Baidoo etc.) will is said to crawl it less if website is slow.
Search Engines are said to Index much better and crawl more frequently into more responsive websites.
Hence implementing SSD to a server and decreasing the page load time should bring up my visitors stats a bit too.

Well that's all for today, hope you enjoyed 🙂

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Howto Fix “sysstat Cannot open /var/log/sysstat/sa no such file or directory” on Debian / Ubuntu Linux

Monday, February 15th, 2016

I really love sysstat and as a console maniac I tend to install it on every server however by default there is some <b>sysstat</b> tuning once installed to make it work, for those unfamiliar with <i>sysstat</i> I warmly recommend to check, it here is in short the package description:<br /><br />

server:~# apt-cache show sysstat|grep -i desc -A 15
Description: system performance tools for Linux
 The sysstat package contains the following system performance tools:
  – sar: collects and reports system activity information;
  – iostat: reports CPU utilization and disk I/O statistics;
  – mpstat: reports global and per-processor statistics;
  – pidstat: reports statistics for Linux tasks (processes);
  – sadf: displays data collected by sar in various formats;
  – nfsiostat: reports I/O statistics for network filesystems;
  – cifsiostat: reports I/O statistics for CIFS filesystems.
 The statistics reported by sar deal with I/O transfer rates,
 paging activity, process-related activities, interrupts,
 network activity, memory and swap space utilization, CPU
 utilization, kernel activities and TTY statistics, among
 others. Both UP and SMP machines are fully supported.


If you happen to install sysstat on a Debian / Ubuntu server with:

server:~# apt-get install –yes sysstat

, and you try to get some statistics with sar command but you get some ugly error output from:


server:~# sar Cannot open /var/log/sysstat/sa20: No such file or directory

And you wonder how to resolve it and to be able to have the server log in text databases periodically the nice sar stats load avarages – %idle, %iowait, %system, %nice, %user, then to FIX that Cannot open /var/log/sysstat/sa20: No such file or directory

You need to:

server:~# vim /etc/default/sysstat

By Default value you will find out sysstat stats it is disabled, e.g.:


Switch the value to "true"


Then restart sysstat init script with:

server:~# /etc/init.d/sysstat restart

However for those who prefer to do things from menu Ncurses interfaces and are not familiar with Vi Improved, the easiest way is to run dpkg reconfigure of the sysstat:

server:~# dpkg –reconfigure



root@server:/# sar
Linux 2.6.32-5-amd64 (pcfreak) 15.02.2016 _x86_64_ (2 CPU)

0,00,01 CPU %user %nice %system %iowait %steal %idle
0,15,01 all 24,32 0,54 3,10 0,62 0,00 71,42
1,15,01 all 18,69 0,53 2,10 0,48 0,00 78,20
10,05,01 all 22,13 0,54 2,81 0,51 0,00 74,01
10,15,01 all 17,14 0,53 2,44 0,40 0,00 79,49
10,25,01 all 24,03 0,63 2,93 0,45 0,00 71,97
10,35,01 all 18,88 0,54 2,44 1,08 0,00 77,07
10,45,01 all 25,60 0,54 3,33 0,74 0,00 69,79
10,55,01 all 36,78 0,78 4,44 0,89 0,00 57,10
16,05,01 all 27,10 0,54 3,43 1,14 0,00 67,79

Well that's it now sysstat error resolved, text reporting stats data works again, Hooray! 🙂

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Apache Webserver disable hostnamelookups “HostnameLookups off” for minor performance increase

Friday, February 12th, 2016


If you don't much care about logging in logs from which domain / hostnames requests to webserver originate and you want to boost up the Apache Webserver performance a bit especially on a heavy loaded Websites, where no need for stuff like Webalizer, Awstats etc. , e.g. you're using GoogleAnalytics to already track requests (beware as sometimes GoogleAnalytics could be missing requests to your webserver, so having some kind of LogAnalyzer software on server is always a plus). But anyways accepting that many of us already trust GoogleAnalytitcs.

Then a great tuning option to use in default domain configuration or in multiple VirtualHosts config is:

HostnameLookups off

If you want to make the HostnameLookups off as a default behaviour to all your virtualhosts on  Debian / Ubuntu / CentOS / SuSE / RHEL distro virtualhosts add either to default config /etc/apache2/sites-enabled/000-default (on Deb based Linuxes) or (on RPM based ones), add directive to /etc/httpd/httpd.conf

For self-hosted websites (if run your own small hosting) or for a home situated webservers with up to 20-50 websites it is also a useful optimization tip to include in /etc/hosts file all the IPs of sites with respective domain names following the normal syntax of /etc/hosts, e.g. in my own /etc/hosts, I have stuff like:

pcfreak:~$ cat /etc/hosts localhost localhost.localdomain pcfreak new-pcfreak fw
# for wordpress plugins
# The following lines are desirable for IPv6 capable hosts

# … etc. put IPs and hostnames following above syntax

As you see from above commented section for wordpress plugins, I've included some common websites used by WordPress enabled plugins to prevent my own hosting server to query DNS server every time. The normal way the Linux / Unix works is it first checks in /etc/hosts and only if the hostname is not defined there then it queries the DNS caching server in my case this is a local DJBDNS cache server, however defining the hosts in /etc/hosts saves a lot of milisecons on every request and often if multiple hosts are defined could save (decrease site opening for end users) with seconds.

Well now use some website speed testing plugin like Yslow, Firebug Fiddler or HTTPWatch


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Windows “God Mode” one shortcut to see and configure all setttings in Microsoft Windows 7 / 8 / 10 – Windows Master Control Panel hidden feature

Monday, January 25th, 2016

One very handy "secret" feature of Windows Operating System which is very useful to people who administrate a dozen of Windows servers daily is called "God Mode".
The idea behind "God Mode" is pretty simple it aims to give you maximum control and viability concentrated in one single Window interface.

God Mode was quite a lot ranted over the past years so it is likely that many of my blog readers are already aware of that Windows secret, but for those who didn't it will be
nice to check it out. To see the God Mode Windows functionality just create a New Folder in Windows Desktop or Anywhere on the Windows PC and Rename the New Folder to:



By creating folder witth his text string you will be able to do almost everything you ever tend to do on Windows from changing the outlook of theme and mouse cursor, changing,
Win explorer's folder's options, modify fonts, change cursor blink rate, get windows performance tools and information, add / remove programs, modify language, modify
firewall settings and in short do everything that is provided by Control Panel + some other goodies like Administrative Tools, Restore Options, Event logs etc. grouped in a fantastic readable manner.
GodMode naming says it all more or less it aims to give you "Godlike" accessibility to the Windows. Of course to be able to properly use the feature you will have to create
the Folder named GodMode.{ED7BA470-8E54-465E-825C-99712043E01C} with Administrator user.
The GodMode is available in Windows OSes since quite a long (2007) and is documented officially by Microsoft

Another alternative shortcut that gives the Godmode Master control panel is:



Enjoy 🙂

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No space left on device with free disk space / Why no space left on device while there is plenty of disk space on drive – Running out of Inodes

Tuesday, November 17th, 2015



On one of the servers, I'm administrating the websites started showing some Mysql database table corrup errors like:


Table './database_name/site_news_list_com' is marked as crashed and last (automatic?) repair failed

The server is using Oracle MySQL server community stable edition on Debian GNU / Linux 6.0, so I first thought during work the server crashed either due to some bug issue in MySQL or it crashed due to some PHP cron job that did something messy. Thus to solve the crashed tables, tried using mysqlcheck tool which helped pretty fine, at many times whether there were database / table corruptions. I've run the following set of mysqlcheck commands with root (superuser) in a bash shell after logging in through SSH:


server:~# /usr/bin/mysqlcheck –defaults-extra-file=/etc/mysql/debian.cnf \–check –all-databases -u root -p`grep -i password /root/.my.cnf |sed -e 's#password=##g'`>> /var/log/cronwork.log
server:~# /usr/bin/mysqlcheck –defaults-extra-file=/etc/mysql/debian.cnf –analyze –all-databases -u root -p`grep -i password /root/.my.cnf |sed -e 's#password=##g'`>> /var/log/cronwork.log
server:~# /usr/bin/mysqlcheck –defaults-extra-file=/etc/mysql/debian.cnf \–auto-repair –optimize –all-databases -u root -p`grep -i password /root/.my.cnf |sed -e 's#password=##g'`>> /var/log/cronwork.log
server:~# /usr/bin/mysqlcheck –defaults-extra-file=/etc/mysql/debian.cnf \–optimize –all-databases -u root -p`grep -i password /root/.my.cnf |sed -e 's#password=##g'`>> /var/log/cronwork.log

In order for above commands to work, I've created the /root/.my.cnf containing my root (mysql CLI) mysql username and password, e.g. file has content like below:




Btw a good note here is its generally a good idea (if you want to have consistent mysql databases) to automatically execute via a cron job 2 times a month, I've in root cronjob the following:


crontab -u root -l |grep -i mysqlcheck
04 06 5,10,15,20,25,1 * * /usr/bin/mysqlcheck –defaults-extra-file=/etc/mysql/debian.cnf \–check –all-databases –silent -u root -p`grep -i password /root/.my.cnf |sed -e 's#password=##g'`>> /var/log/cronwork.log 07 06 5,10,15,20,25,1 * * /usr/bin/mysqlcheck –defaults-extra-file=/etc/mysql/debian.cnf –analyze –all-databases –silent -u root -p`grep -i password /root/.my.cnf |sed -e 's#password=##g'`>> /var/log/cronwork.log 12 06 5,10,15,20,25,1 * * /usr/bin/mysqlcheck –defaults-extra-file=/etc/mysql/debian.cnf \–auto-repair –optimize –all-databases –silent -u root -p`grep -i password /root/.my.cnf |sed -e 's#password=##g'`>> /var/log/cronwork.log 17 06 5,10,15,20,25,1 * * /usr/bin/mysqlcheck –defaults-extra-file=/etc/mysql/debian.cnf \–optimize –all-databases –silent -u root -p`grep -i password /root/.my.cnf |sed -e 's#password=##g'`>> /var/log/cronwork.log

Strangely I got a lot of errors that some .MYI / .MYD .frm temp files, necessery for the mysql tables recovery can't be written inside /home/mysql/database_name

That was pretty weird and I thought there might be some issues with permissions, causing the inability to write, due to some bug or something so I went straight and checked /home/mysql/database_name permissions, e.g.::


server:/home/mysql/database_name# ls -ld soccerfame
drwx—— 2 mysql mysql 36864 Nov 17 12:00 soccerfame
server:/home/mysql/database_name# ls -al1|head -n 10
total 1979012
drwx—— 2 mysql mysql 36864 Nov 17 12:00 .
drwx—— 36 mysql mysql 4096 Nov 17 11:12 ..
-rw-rw—- 1 mysql mysql 8712 Nov 17 10:26 1_campaigns_diez.frm
-rw-rw—- 1 mysql mysql 14672 Jul 8 18:57 1_campaigns_diez.MYD
-rw-rw—- 1 mysql mysql 1024 Nov 17 11:38 1_campaigns_diez.MYI
-rw-rw—- 1 mysql mysql 8938 Nov 17 10:26 1_campaigns.frm
-rw-rw—- 1 mysql mysql 8738 Nov 17 10:26 1_campaigns_logs.frm
-rw-rw—- 1 mysql mysql 883404 Nov 16 22:01 1_campaigns_logs.MYD
-rw-rw—- 1 mysql mysql 330752 Nov 17 11:38 1_campaigns_logs.MYI

As seen from above output, all was perfect with permissions, so it should have been something else, so I decided to try to create a random file with touch command inside /home/mysql/database_name directory:


touch /home/mysql/database_name/somefile-to-test-writtability.txt touch: cannot touch ‘/scr1/data/somefile-to-test-writtability.txt‘: No space left on device

Then logically I thought the /home/mysql/ mounted ext4 partition got filled, because of crashed SQL database or a bug thus, checked with disk free command df whether there is enough space on server:

server:~# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/md1 20G 7.6G 11G 42% /
udev 10M 0 10M 0% /dev
tmpfs 13G 1.3G 12G 10% /run
tmpfs 32G 0 32G 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 32G 0 32G 0% /sys/fs/cgroup
/dev/md2 256G 134G 110G 55% /home

Well that's weird? Obviously only 55% of available disk space is used and available 134G which was more than enough so I got totally puzzled why, files can't be written.

Then very logically, I thought it might be that /home directory has remounted as read only, because the SSD memory disk on server is failing and checked for errors in dmesg, i.e.:


server:~# dmesg|grep -i error

Also checked how exactly was partition mounted, to check whether it is (RO) read-only:


server:~# mount -l|grep -i /home
/dev/md2 on /home type ext4 (rw,relatime,discard,data=ordered)

Now everything become even more weirder, as obviously the disk continued to be claiming no space left on device, while in reality there was plenty of disk space.

Then after running a quick research on the internet for the no space left on device with free disk space, I've come across this great thread which let me realize the partition run out of inodes and that's why no new file inodes could be assigned and therefore, the linux kernel is refusing to write the file on ext4 partition.

For those who haven't heard of Linux Partition Inodes here is link to Wikipedia and a quick quote:


In a Unix-style file system, the inode is a data structure used to represent a filesystem object, which can be one of various things including a file or a directory. Each inode stores the attributes and disk block location(s) of the filesystem object's data.[1] Filesystem object attributes may include manipulation metadata (e.g. change,[2] access, modify time), as well as owner and permission data (e.g. group-id, user-id, permissions).[3]
Directories are lists of names assigned to inodes. The directory contains an entry for itself, its parent, and each of its children.

Once I understood it is the inodes, I checked how many of them are occupied with cmd:


server:~# df -i /home
Filesystem Inodes IUsed IFree IUse% Mounted on
/dev/md2 17006592 17006592 0 100% /home

You see, there were 0 (zero) free file inodes on server and that was the reason for no space left on device while there was actually free disk space

To clean up (free) some inodes on partition, first thing I did is to delete all old logs which were inside /home and files I positively know not to be necessery, then to find which directories allocating most innodes used:


server:~# find . -xdev -type f | cut -d "/" -f 2 | sort | uniq -c | sort -n

If you're on a regular old fashined IDE Hard Drive and not SSD or you have too much files inside this command will take really long …:

Therefore a better solution might be to frist:

a) Try to find root folders with large inodes count:

for i in /home/*; do echo $i; find $i |wc -l; done
Try to find specific folders:

You should get output like:



b) Then once you know the directory allocating most inodes, run the command again to see the sub-directories with most files (eating) partition innodes:


for i in /home/webservice/*; do echo $i; find $i |wc -l; done


One usual large folder which could free you some nodes is the linux source headers, but in my case it was simply a lot of tiny old logs being logged on the system for few years in the past without cleaning:

After deleting the log dirs and cache folder in my case /home/new_website/{log,cache}:

server:~# rm -rf /home/new_website/log/*
server:~# rm -rf /home/new_website/cache/*



a) Then, stopping Apache webserver to check prevent Apache to use MySQl databases while running database repair and restaring MySQL:

server:~# /etc/init.d/apache2 stop Restarting MySQL server
server:~# /etc/init.d/mysql restart

b) And re-issuing MySQL Check / Repair / Optimize database commands:


mysqlcheck –defaults-extra-file=/etc/mysql/debian.cnf \–check –all-databases -u root -p`grep -i password /root/.my.cnf |sed -e 's#password=##g'`>> /var/log/cronwork.log

mysqlcheck –defaults-extra-file=/etc/mysql/debian.cnf –analyze –all-databases -u root -p`grep -i password /root/.my.cnf |sed -e 's#password=##g'`>> /var/log/cronwork.log

mysqlcheck –defaults-extra-file=/etc/mysql/debian.cnf \–auto-repair –optimize –all-databases -u root -p`grep -i password /root/.my.cnf |sed -e 's#password=##g'`>> /var/log/cronwork.log

mysqlcheck –defaults-extra-file=/etc/mysql/debian.cnf \–optimize –all-databases -u root -p`grep -i password /root/.my.cnf |sed -e 's#password=##g'`>> /var/log/cronwork.log

c) And finally starting the Apache Webserver again:

server:~# /etc/init.d/apache2 start

Some innodse got freed up:

server:~# df -i /home Filesystem Inodes IUsed IFree IUse% Mounted on
/dev/md2 17006592 16797196 209396 99% /home

And hooray by God's Grace and with help of prayers of The most Holy Theotokos (Virgin) Mary, websites started again !

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Check Windows load avarage command – Get CPU usage from Windows XP / 7 / 8 / 2012 server cmd prompt

Wednesday, August 19th, 2015


If you used to be a long years Linux / UNIX sysadmin and you suddenly have to also admistrate a bunch of Windows hosts via RDP (Remote Desktop Protocol)  / Teamviewer etc. and you need to document The Load Avarage of a Windows XP / 7 / 8 servers but you're puzzled how to get an overall load avarage of Windows host via command in a UNIX way like with the good old uptime  Linux / BSD command e.g.

 ruth:$ uptime
 11:43  up 713 days 22:44,  1 user,  load average: 0.22, 0.17, 0.15

Then its time to you to get used to WMICWMIC extends WMI for operation from several command-line interfaces and through batch scripts. wmic is a wonderful command for Command addicted Linux guys and gives a lot of opportunities to query and conduct various sysadmin tasks from Windows command prompt.

To get an loadavarage with wmic use:

C:\>wmic cpu get loadpercentage



@for /f "skip=1" %p in ('wmic cpu get loadpercentage') do @echo %p%


on Windows 7 / 8 and 10 as well Windows Server 2010 and Windows Server 2012 for more precise CPU loadavarage results, you can also use:

C:\> typeperf "\processor(_total)\% processor time"

"(PDH-CSV 4.0)","\\Win-Host\processor(_total)\% processor time"
"08/19/2015 12:52:53.343","0.002288"
"08/19/2015 12:52:54.357","0.000000"
"08/19/2015 12:52:55.371","0.000000"
"08/19/2015 12:52:56.385","0.000000"
"08/19/2015 12:52:57.399","0.000799"
"08/19/2015 12:52:58.413","0.000000"
"08/19/2015 12:52:59.427","0.000286"
"08/19/2015 12:53:00.441","0.000000"
"08/19/2015 12:53:01.455","0.000000"
"08/19/2015 12:53:02.469","0.008678"
"08/19/2015 12:53:03.483","0.000000"
"08/19/2015 12:53:04.497","0.002830"
"08/19/2015 12:53:05.511","0.000621"
"08/19/2015 12:53:06.525","0.768834"
"08/19/2015 12:53:07.539","0.000000"
"08/19/2015 12:53:08.553","1.538296"


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Top AIX UNIX Performance tracking commands every Linux admin / user should know

Monday, March 16th, 2015


Though IBM AIX is basicly UNIX OS and many of the standard Linux commands are same or similar to AIX's if you happen to be a Linux sysadmin and you've been given some 100 AIX servers,  you will have to invest some time to read on AIX, however as a starter you should be aware to at least be able to do performance tracking on system to prevent system overloads. If that's the case I advise you check thoroughfully below commands documentation.

fcstat – Displays statistics gathered by the specified Fibre Channel device driver

filemon – Performance statistics for files, logical/physical volumes and virtual memory segments

fileplace – Displays the placement of file blocks within logical or physical volumes.

entstat – Displays the statistics gathered by the specified Ethernet device driver

iostat – Statistics for ttys, disks and cpu ipcs – Status of interprocess communication facilities

lsps – Statistics about paging space

netstat – Shows network status

netpmon – Performance statistics for CPU usage, network device-driver I/O, socket calls & NFS

nfsstat – Displays information about NFS and RPC calls

pagesize – Displays system page size ps – Display status of current processes

pstat – Statistics about system attributes

sar – System Activity Recorder

svmon – Captures a snapshot of the current contents of both real and virtual memory

traceroute – intended for use in network testing, measurement, and management.

tprof – Detailed profile of CPU usage by an application vmstat – Statistics about virtual memory and cpu/hard disk usage

topas – AIX euqivalent of Linux top command

Here are also useful examples use of above AIX performance tracking commands

To display the statistics for Fiber Channel device driver fcs0, enter:

fcstat fcs0

To monitor the activity at all file system levels and write a verbose report to the fmon.out file, enter:

filemon -v -o fmon.out -O all

To display all information about the placement of a file on its physical volumes, enter:

fileplace -piv data1

To display a continuous disk report at two second intervals for the disk with the logical name disk1, enter the following command:

iostat -d disk1 2

To display extended drive report for all disks, enter the following command:

iostat -D

To list the characteristics of all paging spaces, enter:

lsps -a

List All Ports (both listening and non listening ports)

netstat -a | more

The netpmon command uses the trace facility to obtain a detailed picture of network activity during a time interval.

netpmon -o /tmp/netpmon.log -O all;

netpfmon is very much like AIX Linux equivalent of tcpdump To print all of the supported page size with an alphabetical suffix, enter:

pagesize -af

To display the i-nodes of the system dump saved in the dumpfile core file

pstat -i dumpfile

To report current tty activity for each 2 seconds for the next 40 seconds, enter the following command:

sar -y -r 2 20

To watch system unit for 10 minutes and sort data, enter the following command:

sar -o temp 60 10

To report processor activity for the first two processors, enter the following command:

sar -u -P 0,1

To display global statistics for virtual memory in a one line format every minute for 30 minutes, enter the following command:

svmon -G -O summary=longreal -i 60 30

The traceroute command is intended for use in network testing, measurement, and management. While the ping command confirms IP network reachability, you cannot pinpoint and improve some isolated problems

traceroute aix1

Basic global program and thread-level summary / Reports processor usage

prof -x sleep 10

Single process level profiling

tprof -u -p workload -x workload

Reports virtual memory statistics

vmstat 10 10

To display fork statistics, enter the following command:

vmstat -f

To display the count of various events, enter the following command: vmstat -s To display the count of various events, enter the following command:

vmstat -s

To display time-stamp next to each column of output of vmstat, enter the following command:

vmstat -t

To display the I/O oriented view with an alternative set of columns, enter the following command:

vmstat -I

To display all the VMM statistics available, enter the following command:

vmstat -vs

If you already have some experience with some BSD (OpenBSD or FreeBSD) you will feel much more confortable with AIX as both operating system share common ancestor OS (UNIX System V), actually IBM AIX is U. System V with 4.3 BSD compatible extensions. As AIX was the first OS to introduce file system journalling, journalling capabilities on AIX are superb. AIX was and is still widely used by IBM for their mainframes, on IBM RS/6000 series (in 1990s), nowdays it runs fine on PowerPC-based systems and IA-64 systems.
For GUI loving users which end up on AIX try out SMIT (System Management Interface tool for AIX). AIX was using bash shell in prior versions up to AIX 3 but in recent releases default shell is Korn Shell (ksh88).
Nowdays AIX just like HP-UX and rest of commercial UNICes are loosing ground as most of functionalities is provided by commercial Linux distributions like RHEL so most of clients including Banks and big business clients are migrating to Linux.

Happy AIX-ing ! 🙂

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How to install and configure djbdns from source as a Cachening Localhost Proxy resolver to increase resolving efficiency on Debian 6 Squeeze

Monday, August 1st, 2011

It seems DjbDNS on Debian Squeeze has been not included as a Debian package. There is still possibility to install djbdns from an older deb package or install it from source. I however decided to install it from source as finding the old Debian package for Lenny and Etch takes time, plus I'm running an amd64 version of Debian and this might even more complicate the situation.
Installing it from source is not really a Debian way but at least it works.

In this article I assume that daemontools and ucspi-tcp are preliminary installed, if not one needs to install them with:

debian:~# apt-get install ucspi-tcp daemontools daemontools-run

The above two ones are required as DJBDNS is originally made to run through djb's daemontools.

Here is the exact step I took to have it installed as local caching DNS server on a Debian Squeeze server:

1. Download and untar DjbDNS

debian:~# wget -q debian:~# tar -zxvvf djbdns-1.05.tar.gz

2. Add DjbDNS users to /etc/passwd

Creating the below two users is not arbitrary but it's recommendable.

echo 'dnscache:*:54321:54321:dnscache:/dev/null:/dev/null' >> /etc/passwd
echo 'dnslog:*:54322:54322:dnslog:/dev/null:/dev/null' >> /etc/passwd

3. Compile DJBDNS nameserver

First it's necessery to use the below echo command to work around a common Linux bug:

debian:~# cd djbdns-1.05
debian:/root/djbdns-1.05# echo gcc -O2 -include /usr/include/errno.h > conf-cc

Next let's make it:

debian:/root/djbdns-1.05# make

4. Install the compiled djbdns binaries

debian:/root/djbdns-1.05# make setup check
# here comes some long install related output

If no errors are produced by make setup check this means that the djbdns should have installed itself fine.

As installation is compileted it's a good idea to report about the newly installed DjbDNS server if running a mail server. This info is used by Dan Bernstein to gather statistical data about the number of installations of djbdns servers throughout the world.

5. Do some general configurations to the newly installed DJBDNS

Now let's copy the list of the IP addresses of the global DNS root servers in /etc/.

debian:/root/djbdns-1.05# cp -rpf /etc/ debian:/root/djbdns-1.05# ./dnscache-conf dnscache dnslog /etc/dnscache

dnscache-conf will generate some default configuration files for djbdns in /etc/dnscache

Next allow the networks which should be able to use the just installed djbdns server as a caching server:

debian:/root/djbdns-1.05# cd /etc/dnscache/root/ip
debian:/etc/dnscache/root# touch 192.168.1
debian:/root/djbdns-1.05# touch 123.123

First command will allow all ips in range 192.168.1.* to be able to access the DNS server and the second command will allow all ips from 123.123.1-255.1-255 to be able to query the server.

Some further fine tunning can be done from the files:

/etc/dnscache/env/CACHESIZE and /etc/dnscache/env/DATALIMIT

As a last step, before it's running, we have to link the /etc/dnscache to daemontools like so:

debian:/root/djbdns-1.05# ln -sf /etc/dnscache /etc/service/dnscache

If the daemontools is not linked to be accessible via /etc/service it's also a good to link it there:

debian:~# ln -sf /etc/service /

Now the DJBDNS should be running fine, to test if it's running without errors through daemontools I used:

debian:~# ps ax|grep -i readproc
5358 pts/18 R+ 0:00 grep -i readproc
11824 ? S 0:00 readproctitle service errors: ...........

If no errors are displayed it's configured and running to also test if it's capable of resolving I used the host command:

debian:~# host localhost
Using domain server:
Name: localhost
Aliases: has address mail is handled by 0

Now the DJBDNS is properly installed and if you test it for a while with time host localhost , you will see how quick it is in resolving.

The advantage of running DJBDNS is it does not require almost no maintance, its rock solid and great just like all other Dan Bernstein's written software.
Enjoy 😉

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