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Friday, 20 April, 2012

Moving to DISQUS Comment system

The Echo Comments service that I've used for years until now will be EOL-ed in few months and discontinued.

So, I'm moving my site to another comment system called DISQUS. The export/import formats between these systems are completely different and most of data needed for DIQUES are missed, so I'm in way to copy/paste most of conversation threads as a single comment block, still keeping author names and discussion less or more readable ;-)

Sorry if some of data will be lost at the end - it was not intentional..


Posted by Dimitri at 21:01 - Comments...
Categories: x-files...

Thursday, 01 December, 2011

MySQL Performance: Full Time since Today ;-)

Until now, all my work around MySQL Performance was just a part of fun rather my main job... But things are changing since today ;-) I'm moving to MySQL Team, and will work on MySQL Performance full time from now on! ;-) Which is meaning yet more fun (I hope ;-)), more blog posts (I'm sure ;-)), more benchmarks (of course), and more brain work (even more than sure ;-))..

And as I've mentioned benchmarks - many of you complained over a time that we're not really testing what we should.. Well, everything is relative and depending directly on what you're trying to fix or analyze.. ;-) So, I'll not stop running dbSTRESS or Sysbench workloads (or TPCC-like, DBT-2, etc.).. But, I'm also looking for other various test scenarios to reproduce different MySQL performance problems you're observing in your production, or your customer's sites, etc. Please, leave comments on this post, or contact me directly if you prefer. I'll try then to group all such test scenarios together and then ship them as extension to dbSTRESS or any other way (I don't have yet a final test kit, but many ideas are running in my head ;-)), publish performance results and their analyzes (as usual).

As well if you have in mind some top priority performance problems in MySQL 5.5/5.6 - please share them too. I promise you to add them all into my TODO list, and once the impact is validated - see how better it should be fixed (but, of course, I have to be able to reproduce it first ;-)) I'm already have in head issues with adaptive flushing, purge lag delay, Performance Schema overhead, etc. - but you may see other things and have other priorities..

So don't wait - share! ;-)


Posted by Dimitri at 11:30 - Comments...
Categories: MySQL, x-files...

Saturday, 14 August, 2010

EeePC-1005PE & openSUSE 11.2

I've started this year by acquiring a netbook EeePC-1005PE :-)

This post is to share and not forget useful tips to run Linux on EeePC netbook with a success :-)

First - I've wanted to have such a small device for a long time before, but still did not find a small and big enough on the same time :-)

  • Screen become usable since 1024 pixels width, not less :-)
  • Too small keyboard bring too many typos while typing :-))
  • Battery autonomy is very important for freedom :-)

1005PE model (precisely PE) matched perfectly this criteria:

  • Keyboard is absolutely great and usable even with my big fingers! :-)
  • Touchpad is really well integrated :-)
  • Screen is not glassy and very pleasant for eyes! :-)
  • 12 hours of autonomy! (well, under Windows, but means more than 5 hours under Linux :-))
  • Intel CPU single core bi-thread, 250GB disk and 1GB or RAM quite enough for common tasks :-)
  • Intel Video with 2D acceleration randing KDE4 interface so beautiful! :-)

So far, happy owner of the mini-laptop :-)

Of course every day there was at least one colleague who asked the same question - how is it possible to work on the so small "machine".. - well, all depends what do you really need :-) people are very quickly forgetting that just 20 years ago everybody worked on 80x24 video terminal screens :-) and yet 10 years ago 800x600 laptop resolution was not yet a problem :-) - so having 1024x600 resolution makes not a big difference comparing to 1024x768.. - but of course if you cannot live without a big screen don't choose a netbook :-) Personally it's not a problem for me, and it's absolutely exciting to come in the office with a "pocket machine" :-) and keep all you need in a such small computer bag :-))

But well, the next challenge was my desktop migration - I'm using Linux over 12 years now, and since several last year a big lover of openSUSE. Since openSUSE 11.2 creation of the USB live stick was greatly simplified - all you need to obtain a live USB stick is to simply copy the LiveCD image directly to the USB device:

   # dd if=/tmp/LiveCD.iso of=/dev/sdb

where "/dev/sdb" is your USB device (check it first what its name in your system once you've plugged it in)

NOTE: once the copy is finished, you may run "fdisk /dev/sdb" and create a second partition on your USB stick; then this partition will be used to save your local data when you're booting your netbook from the Live USB stick with openSUSE - means that you may keep your live configuration forever with your data and boot from any other laptop / netbook /desktop which allows to boot from USB device! :-)

Then, if you choose to install on the hard disk - installation is going fast and smoothly on 1005PE :-) mostly everything is working except some details you'll need to adjust (as in many cases when you're using Linux :-))

Following a list of my tips I've used on my netbook.

by default a sound level is very low... I've resolved it by adding the following line:

  options snd-hda-intel model=quanta 
intto the "/etc/modprobe.d/99-local.conf" file, after what the sound become "acceptable" :-))


it's very annoying to see the text you're typing to be randomly reformatted just because you've accidentally put your finger(s) on your touchpad :-)) One of the ways to disable your touchpad while typing is to start a following program from a terminal or by launcher via Alt+F2:
  $ syndaemon -i 1 -k -d
And you may find other solutions as well (by installing synaptiks for ex., etc.)


seems to be a common problem for many laptop devices: brightness levels are changing randomly when you're trying to increase or reduce your screen brightness. Following options should be added to your boot line to fix these issues:
   acpi_osi=Linux acpi_backlight=vendor 
then you may also easily change your brightness from the command line:
   $ solid-powermanagement brightness get/set 33  
and assign such actions to any shortcut in case if your Fn+ kays are not working or not recognized by default..

Intel Video Hang

One of the most annoying issues are system hangs due Intel Video Card.. Seems these hangs came since latest changes in the Intel driver code, etc. and can be avoided by installing an old driver, etc... The error messages in your sys log file are looking like this:
Feb 6 12:01:06 dimbook kernel: [ 4067.545514] render error detected, EIR: 0x00000010
Feb 6 12:01:06 dimbook kernel: [ 4067.545562] page table error                      
Feb 6 12:01:06 dimbook kernel: [ 4067.545595] PGTBL_ER: 0x00100000                  
Feb 6 12:01:06 dimbook kernel: [ 4067.545635] [drm:i915_handle_error] *ERROR* EIR stuck: 0x00000010, masking                                                                                      
Feb 6 12:01:06 dimbook kernel: [ 4067.545712] render error detected, EIR: 0x00000010             
Feb 6 12:01:06 dimbook kernel: [ 4067.545753] page table error                                   
Feb 6 12:01:06 dimbook kernel: [ 4067.545787] PGTBL_ER: 0x00100000                               
Some people suggesting to disable KMS by booting with "nomodeset" option set, etc.. - but the workaround I've found which is 100% working for me is: never hibernate your netbook!! :-)) just use suspend to RAM or poweroff :-)) since then by suspend to RAM I've did not reboot ever several months :-)) (why reboot UNIX?.. :-)) of course you've to be sure about your battery, but this EeePC model can sleep 10 days on the battery without problem :-))


Your WiFi connection will become much more stable if you disable the power management of your wifi card :-))
  # ifconfig wlan0 power off

FAN Control

Personally, I'm avoiding to use a laptop having a fan noise :-)) I even prefer it runs on 600Mhz but without any noise, rather on 2400Mhz but noisy :-)) BTW, 600Mhz is largely enough for all common tasks you're doing on your computer :-)) (well, except if your "common" tasks are CPU-bound like games or streaming, etc. ;-)) Also, a it's always easier to accept a constant low noise, rather jumping periods from silence to noise every time :-)) and the default EeePC setting I'd call pessimistic rather optimal :-)) I've found many interesting posts about fan noise on EeePC, some people even suggesting to remove the fan physically from your netbook and saying there is no any danger :-)) Well, I've found a reasonable workaround with a setting via command line - you may easily switch from BIOS (automatic) management to the manual management, and then set the fan speed according your feeling:
check control (0= BIOS, 1= manual)
   # cat /sys/devices/platform/eeepc/hwmon/hwmon1/pwm1_enable

switch to manual:
   # echo 1 > /sys/devices/platform/eeepc/hwmon/hwmon1/pwm1_enable
switch back to BIOS:
   # echo 0 > /sys/devices/platform/eeepc/hwmon/hwmon1/pwm1_enable

Set FAN Speed:
   # echo 10 > /sys/devices/platform/eeepc/hwmon/hwmon1/pwm1
   # echo 40 > /sys/devices/platform/eeepc/hwmon/hwmon1/pwm1


Then another optimization to increase your autonomy time while on batteries is to enable EeePC Hyper Engine: it improved my autonomy time from 6 to 8 hours! :-))
 Check HyperEngine state:
   # cat /sys/devices/platform/eeepc/cpufv

 where the last digit:
   0= Perf
   1= Default
   2= Powersave
   (ex. x301 = Default)

 Enable Powersave:
   # echo 2 > /sys/devices/platform/eeepc/cpufv

That's all from my list..

Seems there are many improvements came with openSUSE 11.3 now, but I'm not changing a horse which is working already very well and will stick with 11.2 until nothing forcing me to upgrade :-))

If you have any other tips / findings, please share! :-))

Posted by Dimitri at 10:33 - Comments...
Categories: Linux, x-files...

Sunday, 16 August, 2009

Butterfly & Summer...

X-files category grouping all posts "about nothing" :-) or just yet more another occasion to say that life is beautiful and plenty of surprises! :-)

Hard to resist and not to think about life beauty while looking on a butterfly... :-)

But when you discover such beautiful specimens inside of your proper garden - you find yourself smiling like a child :-)

Large Tortoiseshell / Grande Tortue & Peacock / Paon du jour

The most common, but so fun :-)

The Swallowtail / Machaon

Don't know why, but Machaon was always my preffered butterfly as far as I remember myself :-) The King (or Queen) Butterfly - as you prefere :-)

Scarce Swallowtail/ Flambé

Very beautiful butterfly, seems to be very rare nowdays in France... We're happy they like our garden! :-) Flambés and Machaons are flying like birds... And the most magic is to observe them plane..


But well.. When butterflies are gone - Summer is finished...

Posted by Dimitri at 16:23 - Comments...
Categories: x-files...

Sunday, 19 April, 2009

Hello World! :-)

Did not expected to write any blog until today, but seems it's the most adapted news sharing solution :-)
Will try to adapt it now...

My main home page is http://dimitrik.free.fr
And blog entries will be used as news feeds rather to tell you my life :-)

Posted by Dimitri at 14:21 - Comments...
Categories: x-files...