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31st May 2019
I'm writing the blog in English because I type twice as fast this way than in Russian (yes I am improving...), and 90% of my friends and : friends
can read English any way. I answer comments in the same language they are posted.
I am trying not to post anything related to my employer, but if I do so, this expresses only my own views and does not represent an official position of my employer.
When I post about some technical topic which seems non trivial and is related to my employer's product, don't expect it to be inside information. If I post about it, it means that this info is already public. Usually I do not post any personal information or anything that is related to my family.
All photos are mine, and I allow anyone to copy, change, do anything you please with them. I don't post "friends only".
Useful tags are: software
and trip report
30th June 2016
Julia just told me about an encounter with a typical german gentleman, ~50 y.o. She parked near his house (parking was allowed there), and he was staring at the car. She asked if everything is alright, and told him she will drive away in 10 minutes, and that she can park elsewhere if he needs this parking place. :
His answer was: "No, it is ok for you to park here. But you see, you wheels are not perfectly aligned! Not good." Front right wheel was about 10cm further from a curb than rear right wheel...
20th June 2016
Jacob - Kazanova
Jacob always liked girls. :
This weekend, he was playing with a little girl (G) - 2.5 y.o. (Jacob (J) is now 2.0 y.o)
(J) - Пойдем туда, в комнату!
(G) - Нет!
(J) - Пойдем туда, в комнату! (Берет девочку за руку, тащит, та упирается, не идет.)
(Мама) - Зачем в комнату?
(J) - Массаж! (Девочка перестает упираться, заинтересовано идет с Яшей в комнату.)
17th June 2016
Skylake is the currently selling CPU, and it is a good one. (I have it in my home desktop too). :
But there is a small undocumented regression. It should not bother anyone, unless in very specific settings.
Here is the code to test it:( Read more...Collapse )
The code just reads RTC (but does not parse the output). On Broadwell, previous gen, it takes less than 1k cycles. On Skylake, it takes 200k-500k cycles. Why? If you would read MSR 0x34 (SMIs handled since boot) before and after the test on Broadwell, the increment will be 0. On Skylake, it would be 2.
So any IN or OUT operation on ports below 0xff are now handled in SMI. This is legacy IO that is rarely used in a modern OS, and even if it is occasionally used, ~10 microseconds delay would not affect performance. Unless you are trying to control equipment with 31.25 microsecond response time ;)
12th June 2016
Jacob speaks, 2yo
Jacob is few days short from 2 years old. Here is his thinking about future: :
- Яша будет врач.
- А не инженер?
- Нет. Яша будет строитель.
- Что будет строить Яша, домики?
- Нет, Яша строить завод!
- А что за завод? Что будет производить завод, который ты построишь?
- Мотоциклы! .... И вертолеты.
9th June 2016
Be right back!
Until end of 2016 (at least) I am back as the main realtime performance issues solver in Europe in our org. :
Only in 50% capacity - the rest stays with NFV performance on Intel servers.
I already got a very nice embedded Skylake board on my desk, and a pipeline of performance issues to investigate and hopefully to resolve. Last 2 days I spent at customer factory wearing white doctor's coat, doing what I described to Jacob as "папа у клиента чинит робота. папа - инженер."
4th June 2016
No wonder PC sales are going down for 8 years in a row (I hope VR would change this trend, if not in units but in revenue) :
But in my experience today high end PCs are less robust than in 90s and 2000s.
First, a motherboard of my new PC broke down after 1 week of operations. There were no apparent burns, and if I manually short PC_ON it starts CPU fan, but nothing else. Anyway, the board I got from US, it was cheap and it was not practical to return it.
So I went to south of Hauptbahnhof to buy a new MB: this time, MSI with Z170 chipset. I assembled it, and POST failed because of DRAM. OK, then I successfully booted with single DRAM module. Then with two DRAM modules. Then with all four modules, but I had to manually switch DRAM frequency from 2.6Ghz to 2.1Ghz. So now it works, but I am bitter as I paid premium for faster DRAM and can't use it at the marked speed.
30th May 2016
My new desktop.
My last desktop was Pentium 4 (Northwood) based, Gygabyte motherboard with Intel chipset, Nvidia graphics. I used it in 2002-2004. :
Since that time, I never used desktops at home. (I had access to too many "fresher than new" dekstops at work, with maxed specs and stuff.)
But now I just got another one at home:
CPU is i7 6700K at 4.4Ghz (I bought it with a very big discount, unfortunately I am not allowed to disclose it).
The motherboard is GIGABYTE H170M-D3H. It is very cheap, and I don't mind the limitations of H170 chipset: having just one full speed PCIe slot (so no SLI) and limited overclocking (6700K is unlocked anyway).
Graphics card: waiting when 1070 is available...
The config is for VR, and also I noticed that even my trivial experiments with tensorflow take too long on my Macbook pro 2012; and I don't want to abuse my servers in a datacenter.
Upd: On overclocking, I am not a big fan, because reliability drops and desktop SKUs are already less reliable than server and embedded. Still, I installed a liquid cooler from Intel (value deal $ too, he-he) because Yulia asked me to make the system quiet, and with good cooling I have some headroom in CPU freq.
23rd May 2016
Autobahns are great?
I am not very fond of driving. So next time we go north we can just take a train... with our car ; :
Like this gentleman on a Porsche who took a train from Berlin or Hamburg and arrived to Munich in the morning. Cool service, is it?
21st May 2016
Jacob speaks, again
Now at 1 year and 11 months, still zoo is the favourite subject to talk about. :
- А в зоопарке.. Там лев! Придет к Яше. Опасно! Укусит Яшу лев! Папа расстроится... А мама придет и спасет!
- Ага, мама спасет от льва, и хобот ему оторвет.
17th May 2016
There is nothing else around but VR, IOT and deep learning. And combinations of thereof like IOT+5G+Deep learning+autonomous driving. :
13th May 2016
Positive discrimination in the airport
I am in MUC airport now, waiting for my flight to Duesseldorf. Just had a funny moment recently. :
When I was standing in a line for security control, two lines were merging before the X-ray machine. It was zip merge, as usual, and ppl in the end of the line were standing behind each other, located slightly closer towards a line they were coming from. When I was first in the line, I was invited to the X-ray machine, and then immediately a member of security stuff asked me to step back and give way to a passenger who was standing behind me in the line. I complied, and eventually asked why break a zip merge?
The answer was, I quote: "yes it is zip merge, but men should yield for wifes, so wifes have priority." Needless to say, my wife was not with me at the moment ;)
p.s. confusing "woman" and "wife" word is very common for German native speakers, even when their English is good.
10th May 2016
Latest from Jacob
Here are his best phrases when he was 1 year 10 months old: :
- Яша, не надо обнимать ножик! [игрушечный]
- Ножиком можно порезаться, и люди не обнимают ножики.
- Кто не обнимает ножики?
- Люди не обнимают ножики. А Яша обнимает ножики!
In the zoo:
- Лев съест?
- Лев в клетке, поэтому не опасен.
- Лев идет к Яше! Не надо!!! [убегает, прикрываясь папой]
- Какие животные были в зоопарке?
- Слон, жираф, лев, обезьяна огутан, обезьяна гамадил.
- А кто из них больше всех тебе понравился?
9th May 2016
Yet another interesting book from samlib
The : author
claims he writes hard sci-fi superhero comic novel. Much like in "Цветок камнеломки", the book is about singularity. As Bostrom noted, one of possible causes of the singularity could be a strong AI developed by a small dedicated team "in a garage".
This book is about a discovery in physics that triggers singularity, but unlike "Цветок камнеломки" the settings are modern, not USSR. Also protagonists come from social and educational background that I understand quite well.
Unfortunately as action evolves and more ppl gain "supepowers", the script turns much closer to other books from samlib.ru where main characters are super-spetznaz types who fight with "пиндосами" and "масонами". Completely weird - reading something where jokes are familiar and protagonist's figure is even more familiar, but he still fights with illuminati and other enemies of Russian state.
20th April 2016
Developerz, developerz... Windowz debugging.
Now real stuff comes: :
After weird setup experience
I need to do a real work: set a breakpoint on an undocumented windows kernel API function.
Windbg then. OK, when running windbg locally one can't use breakpoints. OK, remote then. On host, modern Visual studio only supports remote debugging over ip. But Windows 7 target does not. Ok, windbg host then. Remaining connectivity options are FireWire, USB and COM. There is no Firewire on target. There is no COM on target. COM over USB won't work because :).
That is it folks. All one should know about Windows driver/kernel debugging.
19th April 2016
One can't just install Windows 7 embedded 32 bit on Skylake
To reproduce a performance regression reported by customer I had to install Windows 7 embedded 32 bit on Skylake NUC. It took me a while! Don't know why manually installing USB3 drivers to Windows 7 install images does not work every time, and no idea why it breaks user services. Still after 2 weeks of part time work it is finally up. :
It was worse than trying to manually compile some major open source project with all dependencies tree on Yocto Linux running on pre-production hardware :) - because there is no source to look at when something breaks, no logs and weird error messages.
13th April 2016
Here is what I spotted in an U-Bahn yesterday. :
Cool! I did not know IntelliJ is so rich so they can afford this type of ads in public transport. Besides, what about ad targeting :) ?
Full pic and explanation is under the cut.( Read more...Collapse )
7th April 2016
When coming to Aying/Poing, they sell animal food at the gates. The trick is that animals are literally fed up with this food. And this is the only sure way to get close to an animal. :
But they love carrots and apples :)
And this is when Jacob told the longest sentence so far, at 1 year and 9 months:
"Аалень!!! Отдай морковку Яше!!! Отдай! Отдай! Отдай!!!"
I should not have made him give a carrot to a deer, Jacob apparently planned to eat it himself.
4th April 2016
There is a common story with with some customers I help with s/w performance: :
First they come and tell that they expect the server to perform ~1.3x better on their workload. After some analysis I tell them: yeah, you can achieve it by upgrading from your 2.6.18 kernel (even 2.6.9 :( ) to at least 3.10. Or upgrade JVM from 1.5 to at least 1.7.
No, they tell, we need a magic trick to have at least 30% performance improvement, but without upgrade. The best would be a magic BIOS switch combination... Or software recompile with different compile flags.
Actually sometimes a magic BIOS combination plus different compiler/flags actually provide extra ~15%..
31st March 2016
Bad snorkelling [2/2]
Still I was a bit disappointed: :
In the Red Sea, even in Eilat, there is more diversity in coral species. Even more so in Indonesia.
More fish and the most dangerous animal in the sea are under cut.( Read more...Collapse )
All pics are in the album
30th March 2016
It is very difficult to get close to this crab. It spots me from several meters, quickly runs to its burrow and hides there. :
However I managed to make this picture using a macro lens from about 30cm. And this was a great experience. Because of jet lag, I woke up at 6AM, and went outside at 6.20, while Yulia and Jacob were both still sleeping. At 6.25, sun started rising, and all crabs that were lurking around a beach suddenly stopped moving and started staring at sun.
That looked amazing! I just went to this one, and it did not run and hide as usual. It was too busy watching the sunrise... I read somewhere before that crabs do enjoy sunrise, but I never checked as I never woke up early enough in my previous trips to tropical islands.
Hermit crabs watch sunrise too: ( Read more...Collapse )
19th March 2016
Bad snorkelling [1/2]
Most reviews of our hotel I read on tripadvisor indicated "bad snorkelling". Let's see... :
This unicornfish and a small shark swam just ~30 meters from our room door. (20 meters to the shore, then 10 meters towards the reef). But there was a small trick.. I actually chased these two buddies towards the coast from deeper waters :)
Some more sea life under cut.( Read more...Collapse )
18th March 2016
Home sweet home
I am back online. :
Very good freediving and snorkelling experience it was, now when Jacob is almost two it is much easier to travel with him.
P.s. I will get back to my work stuff on Monday.