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You are viewing the most recent 25 entries.
31st May 2019
10:08am: This blog
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 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 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 , idea , Deutschland, freediving and trip report
18th May 2013
5:25pm: Once again, arrived to Israel, first impressions.
The first thing I did was of course swimming a kilometer in the sea. The beach is located right next to my hotel. Here is a view from my hotel room:  When I was passing through the passport control, an officer greeted me in English, then took my documents. Her first question was: "Gde vy prozhivaete?" I did not get it completely, but quickly answered: "I live in Munich. What was your question again, did I get it right?" Then she asked: "Vy govorite po russki?" And this solved it: I did not realize she was addressing me in Russian :) Before coming here, I engaged to a conversation with the customer I am visiting. Customer is in Israel and it shows: never before I had a bargaining exercise like this with a client: - We need 45% performance improvement! Please come to us and show what you can do. - I know your code quite well already, and it is good. So no low hanging fruits. There is optimization A, will get you 2%, then B will get you 3%, then another one will give you 10% but will require a lot of small changes in the code. The first scales OK with the third, but not with the second. Plus or minus couple of points. Overall you'll get about 10% give or take. - No we need 45%, at least 40%. Can you do better? - Well I can do X and Y, each potentially providing an additional 2%, but it will make your code more complex. Do you really need it? - OK you were talking about averages, can you tell what would the best case be, if everything works out smoothly? Can we approach 30%? - Well if all optimizations I am envisioning scale perfectly (which never happens) you'll get ~16%. ... ... ... I feel like I am selling fruits at a bazaar. Will see tomorrow how it goes...
16th May 2013
8:31am: habr post on PLC compilers and IDEs
Posted an article about IEC61131-3 compilers and IDEs on habrahabr. Because of selfish reasons :) I posted it few days ahead of a planned date, and it shows: I never had as bad downvotes ratio on my posts before.
15th May 2013
11:01am: Gather
Same code, when compiled and ran for Ivy Bridge and Haswell by Intel compiler works much faster on HSW than on IVB. (Can't disclose exact speedup as HSW is not yet released, but new instructions involved in speedup are not secret for a while and so are BKMs)
#define A (2*1024)
#define B 64
int a[A]; int b[B];
void main()
{
int i,j,sum = 0, min = 100000000;
ticks t1,t2;
for (i = 0; i < A; i++) a[i] = i; // Init arrays
for (i = 0; i < B; i++) b[i] = (i*113 + 113) % A;
for (j = 0; j < 10000; j++)
{
sum = 0;
t1 = rdtscll();
for (i = 0; i < B; i++) sum += a[b[i]];
t2 = rdtscll();
if (min > (t2 - t1)) min = t2 - t1; // measure best case, dont warmup
}
printf ("sum = %i, min = %i\n", sum, min); // print sum to trick compiler
}New gather instructions are useful, and compiler uses them automatically. Of course there are no miracles - as I increase A and B, performance goes down, and eventually becomes on par with old implementation because memory latency becomes a limiting factor.
14th May 2013
9:48am: Losing 3 holidays.
This Saturday: working on a plane to Israel. (My productivity goes up when I am in transit, I don't know why but it works) This Sunday: working at customer site in Israel, they have a custom to work on Sundays!!! :( Next Monday: working day in Israel, public holiday here in Bavaria. Poor, poor me :) On the bright side, they promise +11 and rain in Munich on Sunday, and +32, sunny weather in Tel Aviv. I do not have firm plans for the evenings yet, I guess 1 or 2 evening I dine with colleagues, and the rest I'll just spend on the beach. (Is it jellyfish season yet?) Would be great to meet with lj friends in Tel Aviv.
12th May 2013
12:41pm: Botanical garden, Munich
May 9th was a public holiday in Germany this year (unusual), so we sent to Munich botanical garden. We've been there once 3 years ago, but it was not the right season, and most of greenhouses were closed for renovation. Now the timing for a visit was very good. Everything is blooming, including spruce. ( Read more...Collapse )All pics are in a picasa album
11th May 2013
10:45am: First sunny days in English garden
English garden is a perfect place to go to when there is not enough time or motivation to explore something further away. We walk there or cycle almost every weekend weather permitting, and still keep finding some new things we have not seen yet. This time we figured out why the grass in the park is always green and lush. I had very rarely seen lawnmowers in the park, and considering the park's size lawnmowers should be constantly operating. Instead they have decided to use a greener approach. They took ~1000 sheep, installed an electric fence around them and keep moving the fence so the sheep mow the grass.  Do you have some grass? What if I find something?? ( Read more...Collapse )
10th May 2013
6:04pm: Trip report: Västerås
This week I went to Västerås to meet with a customer, spent 20 hours away from home. As usual, I did not have any time to see around the town: I arrived there at 1.30AM, and went back to Munich at 4PM same day. The only pic I made was in a canteen at customer site:  Of course this bank note is not real, it is realistically drawn on stairs so newcomers like me are trying to pick it up.
8th May 2013
7:52pm: Snegov
Just finished reading Норильские рассказы. I think it is the best thing in the genre, I liked it more than Shalamov and Solzhenitsyn. Dovlatov may be a better stylist, but for me he is a bit too sarcastic. Where Shalamov describes evil russian gangsters, Solzhenitsyn describes evil Soviet government, and Dovlatov tells that we are all surrounded by absurd and stupidity, Snegow calmly describes people he met in the prison and in Norilsk, including top scientists and gangsters, politicians and engineers, GULAG officials and NKVD officers. Among all those groups, the author finds interesting people worth respecting. It was very touching moment to read when the author was suffering from scurvy and anemia and forced to dig ground, he was discussing mathematical foundation of general relativity with other inmates. When the author was moved to work in first Norilsk nickel smelter as engineer, the story became more interesting and tense. As an engineer too, I felt compassion to the author when he described that he was given orders to improve the yield of Nickel by 20% or else. Or else in 1943 was scary. I wonder, if I was moved to the "sharashka" environment, would my productivity in Lines Of Code go up or down???
5th May 2013
6:52pm: Back home from Italy
Just got back home from a short trip to south Tirol.  Our permit to use Austrial autobahns is valid for 9 more days, I think I know where do we go next weekend (unless it rains).
3rd May 2013
10:02am: Wildpark Poing 2
It is a great time to visit the Poing zoo. Most of the animals are nurturing new born babies, and birds are either mating or building nests. May be 1st of May was not the best day to come there because of the huge crowds of visitors. 90% come with children, 10% come with a zoom lens. As we don't have children yet, I had no choice but to bring a zoom lens.  River rat youngsters fighting. ( Read more...Collapse )The entry price is 6.50 for adult ticket, and it is just 20 minutes drive from Munich city center. All pics are in picasa album
1st May 2013
10:15am: Walking around Munich center
Yesterday I took a day off, so only had to spend half day at work :) Other halve day I spent working around Munich city center.  This looked like a group of local students studying film making shooting a part of their diploma work. ( Read more...Collapse )
30th April 2013
11:50am: Productivity
When coding, being in the "flow" helps. There are well known methods how to enter and how to keep this state. Some of the methods are more or less applicable for everyone. For me, the top three factors that help getting the "flow" are 1. Interesting work (not unusual), 2. Deadline approaching soon. (I am not proud of this fact but I guess it is common), and my favorite: 3. Being just on and around a trip to customer. In that case, flying somewhere helps the most, then goes ICE train, then driving, then using public transport. (The mean I use for travel depends on the distance). I have no idea why it helps me a lot. By the way 80% of the worthwhile ideas related to my work come to my head when I am travelling for business :). Anyone has similar experience?
21st April 2013
6:51pm: Public swimming pools in Munich
A building on the right side of a photo is located in the center of Munich on the right side of Isar.  It is the oldest public swimming pool - Volksbad. It is about 100 years old. The swimming lanes are 30 meters long. There are 3 lanes - 2 for sporty swimmers, and 1 wide lane for others. The depth is 3.5 meters to 50 centimeters. It is usually not crowded, and the interior is really beautiful. My impressions from other swimming pools - under cut. ( Read more...Collapse )
20th April 2013
10:52am: Strange drawing in a swimming pool
Usually I go to Michaelibad or Volksbad, but some times I go to Kosimabad. Recently I noticed there is an exhibition of children's drawings on display in Kasimabad hall. All drawings are very similar, except for this one:  I like the drawing, especially that women wear nice dresses. However, the slogans are a bit scary. From right to left, they are: "One", "Arab", "Irak is one"(with a typo), "God is great" (Allah Akbar), "Death". In a next post, I'll write a review of public swimming pools of Munich.
17th April 2013
1:12pm: Industrial revolution 4.0
Just published a short article on industrial revolution 4.0, Ethernet based fieldbuses and an ad for Intel I210 NIC. When writing about fieldbuses I made several minor omissions, simplifications and probably mistakes too. I know that several real professionals in automation are reading my blog, can you guys point me any mistakes I made in describing fieldbuses? My experience is limited to optimizing their s/w stacks.
16th April 2013
8:12am: Commute
I use A94 for commute. It usually takes just 10 minutes, and goes past Munich trade fair (Messe). Very often there are some fairs but I have never seen traffic jams on the autoban at that places before. Unfortunately last few days it takes me 20 more minutes than usual to get to work.  All because of this building cranes trade fair. I hope it ends soon so I can drive 150km/h as usual, not 50km/h as yesterday.
15th April 2013
8:36am: Declare the late spring open
Spring had started in Munich at last.  Yesterday there were crowds of ppl everywhere enjoying the sun and a first really warm day of spring. Julia and me tried to find a free ping-pong table, but no avail.
13th April 2013
11:52am: Best wine comes out of an old vessel. [2/2]
In a previous post I mentioned a very interesting LJ of a retired professor and promised to post a link to another one. The second LJ of a retired professional I found few years ago is LJ of a former KGB/FSB general, who was deployed in Afghanistan twice (right after the war started and just before it ended). He writes great novels about Afghanistan and about KGB/FSK operations in early 90-s in his blog. In a recent post he refuted those who thought he is not the person he pretends to be, and had never fought in Afghanistan. He picked a Soldier Švejk for one of his avatars, and I think he has a good reason. The protagonist in his novels very often resembles this noble soldier. Like Dr Berezin, detnix often writes series of posts telling a story. Some series describing late 80-s, early 90-s can be found under this tagInterestingly enough, political views of detnix and berezin-fb are similar. It is very interesting to read the bits written by detnix that reveal the professional paranoya: "Я аплодирую Фэйсбуку: из шести предложенных персон только одну я так и не смог опознать. А что у них еще есть в загашнике! Так скажите на милость, какая спецслужба у нас главная? Та, что на Лубянке, или то сообщество, что раскинуло свои щупальца по всем узлам глобальной сети? Мне также интересно, а наши так могут? Когда я уходил со службы, в Конторе в этом смысле "и конь не валялся!". Хотелось бы верить, что мы и здесь "впереди планеты всей" или хотя бы - на уровне. Но тогда почему в тех же "одноклассниках" я встречаю весело щебечущих действующих сотрудники наших спецслужб? Или теперь после последнего провала все можно? Хотя, это тоже риторические вопросы. Достаточно вспомнить: за рубежом осели наши советские (!!!) деньги в частных вкладах в размере 500 млрд. Почти все (!!!) дети высших чиновников учатся за рубежом. В проклятые годы тоталитарного СССР мы бы такой шанс не упустили. А они?..." (c) detnix Unlike wannabe conspiracy theorists, this gentleman probably knows wheat he writes. The only sorrow thing about detnix is his conflict with anhar. I respect anhar because I used here services as a toor guide in middle east twice (on 2003 and 2004) and she was very professional and helpful. By the way. Could someone advice me if there are any other interesting blogs by retired folks to read?
2nd April 2013
11:18am: Best wine comes out of an old vessel.
Few years ago I was thinking: the most interesting blogs are written by the brightest professionals: engineers, doctors, managers, scientists. However, they often have timing and confidentiality constraints so they cannot share most interesting insight they have. But there must be some who are now retired and who are willing to share their vast professional experience. I think livejournal is a perfect medium for a live memoir genre, including live discussions with readers. I have to admit I only found two so far. The most notable example is a LJ (in Russian) of Dr. Berezin. For a layman like me, he is most famous for MMPI adaptation. He is writing about different topics, but one I like most is series of posts where he narrates stories from his practice as a psychologist. Such stories often illustrate how science and industry were operating in Soviet Union times. His journal title is "One live through four epochs" for very a good reason. His stories show how society of Soviet Union was changing as time passed. For instance, I enjoyed a story he published few months ago about his client, a physicist. He uses pseudonyms for his patients, but in some cases like this one he provides enough details so it is theoretically possible to de-anonymize. Another example is a story of "Фселикос". The patient's name was also changed. However he is so famous that I knew the real name from a very beginning. And he had enough pseudonyms so I do not quite understand why he needed another one. For a technical folks like me who are interested in CPU design and manufacturing there is another interesting story is about Soviet CPU manufacturing. And I love the communication style of Felix Borisovich! He responds to every comment he receives in his blog posts, sharing even more interesting insights. It is very rare thing to see someone in internet using proper Russian language even in comments. I'll point to another LJ I found in a next post.
31st March 2013
7:25pm: Trip report: Zwiesel
Two days off for a Catholic easter came handy. We went to Bavarian Forest mountains for hiking.  When hiking in the woods, we have not seen any animals, let a lone a Wolpertinger. We hoped we will encounter start of spring, but in fact it was winter. It was a too late for skiing, and too early for hiking, so we were the only guests in a small family hotel. The hotel owner suggested we can stay in the bar and try to see a wolpertinger right there, but instead we went to the woods. ( Read more...Collapse )More about Zwiesel in a next post.
26th March 2013
8:58pm: Ich hab Haus, Ich will nicht raus
Strange that I have not seen this earlier. Sorry if it is a duplicate. From a German TV: The video clip is old, posted 6 years ago but still funny.
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