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Search - "threading"
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Toilets and race conditions!
A co-worker asked me what issues multi-threading and shared memory can have. So I explained him that stuff with the lock. He wasn't quite sure whether he got it.
Me: imagine you go to the toilet. You check whether there's enough toilet paper in the stall, and it is. BUT now someone else comes in, does business and uses up all paper. CPUs can do shit very fast, can't they? Yeah and now you're sitting on the bowl, and BAMM out of paper. This wouldn't have happened if you had locked the stall, right?
Him: yeah. And with a single thread?
Me: well if you're alone at home in your appartment, there's no reason to lock the door because there's nobody to interfere.
Him: ah, I see. And if I have two threads, but no shared memory, then it is as if my wife and me are at home with each a toilet of our own, then we don't need to lock either.
Me: exactly!12 -
Most satisfying bug I've fixed?
Fixed a n+1 issue with a web service retrieving price information. I initially wrote the service, but it was taken over by a couple of 'world class' monday-morning-quarterbacks.
The "Worst code I've ever seen" ... "I can't believe this crap compiles" types that never met anyone else's code that was any good.
After a few months (yes months) and heavy refactoring, the service still returned price information for a product. Pass the service a list of product numbers, service returns the price, availability, etc, that was it.
After a very proud and boisterous deployment, over the next couple of days the service seemed to get slower and slower. DBAs started to complain that the service was causing unusually high wait times, locks, and CPU spikes causing problems for other applications. The usual finger pointing began which ended up with "If PaperTrail had written the service 'correctly' the first time, we wouldn't be in this mess."
Only mattered that I initially wrote the service and no one seemed to care about the two geniuses that took months changing the code.
The dev manager was able to justify a complete re-write of the service using 'proper development methodologies' including budgeting devs, DBAs, server resources, etc..etc. with a projected year+ completion date.
My 'BS Meter' goes off, so I open up the code, maybe 5 minutes...tada...found it. The corresponding stored procedure accepts a list of product numbers and a price type (1=Retail, 2=Dealer, and so on). If you pass 0, the stored procedure returns all the prices.
Code basically looked like this..
public List<Prices> GetPrices(List<Product> products, int priceTypeId)
{
foreach (var item in products)
{
List<int> productIdsParameter = new List<int>();
productIdsParameter.Add(item.ProductID);
List<Price> prices = dataProvider.GetPrices(productIdsParameter, 0);
foreach (var price in prices)
{
if (price.PriceTypeID == priceTypeId)
{
prices = dataProvider.GetPrices(productIdsParameter, price.PriceTypeID);
return prices;
}
* Omitting the other 'WTF?' code to handle the zero price type
}
}
}
I removed the double stored procedure call, updated the method signature to only accept the list of product numbers (which it was before the 'major refactor'), deployed the service to dev (the issue was reproducible in our dev environment) and had the DBA monitor.
The two devs and the manager are grumbling and mocking the changes (they never looked, they assumed I wrote some threading monstrosity) then the DBA walks up..
DBA: "We're good. You hit the database pretty hard and the CPU never moved. Execution plans, locks, all good to go."
<dba starts to walk away>
DevMgr: "No fucking way! Putting that code in a thread wouldn't have fix it"
Me: "Um, I didn't use threads"
Dev1: "You had to. There was no way you made that code run faster without threads"
Dev2: "It runs fine in dev, but there is no way that level of threading will work in production with thousands of requests. I've got unit tests that prove our design is perfect."
Me: "I looked at what the code was doing and removed what it shouldn't be doing. That's it."
DBA: "If the database is happy with the changes, I'm happy. Good job. Get that service deployed tomorrow and lets move on"
Me: "You'll remove the recommendation for a complete re-write of the service?"
DevMgr: "Hell no! The re-write moves forward. This, whatever you did, changes nothing."
DBA: "Hell yes it does!! I've got too much on my plate already to play babysitter with you assholes. I'm done and no one on my team will waste any more time on this. Am I clear?"
Seeing the dev manager face turn red and the other two devs look completely dumbfounded was the most satisfying bug I've fixed.5 -
Dev: This could be sooooo easily optimized...
Me: Uhm. Don't think so. What's your idea?
Dev: Just use threads.
Me: Nope. Problem requires 3 shared resources per process step, it won't be faster by threading. Shared resource will only lead to locking contention, decreasing performance.
Dev: I don't think that will happen. Can you PROOF to ME that this will happen?
Me: It was your suggestion, so you should proof me wrong. Nice try, but no thanks.
Dev: Yeah, but it's too slow and it should run faster.
Me: If you cannot find a better approach than the current one, it runs as fast as it can while providing correct results. That's not slow. That's just working as intended and designed.
Dev: Yeah, but it's still slow.
....
You know these conversations where you just wanna rip some people's face off, stick it in the shit hole they use to talk and toss them out of the window....
Yeah. Had those conversations today.10 -
I guess my best AHHA moment was back when I learned that good code is simple code.
When I started out I wanted to prove myself by showing of how good of a programmer I was(and which I retrospectively wasn't) , which basically meant to use every high level concept I was aware of whenever possible. Multi threading where linear execution would have been totally okay, polymorphism with x meta classes where a switch would have been enough, all that shit.
It wasn't until I had to guide the first person through that mess of useless ego stroking that I found out how much time and money I wasted by not going with the easiest approach that solves the problem.
Took me some time to fully lay off that attitude but it surely was one of the most influential moments of my career.6 -
Have I mentioned lately how much I LOVE the stability of slack (and electron apps in general)?
Got notified of a new message in slack, clicked the channel and this is what I see, even after a restart. No content or UI controls of any kind are being rendered. No workspaces, no loading spinners, no errors, no warnings ... just nothing.
I don't give a fuck about your integrations, apps, giphy, video calls, search, threading ... I just want to read text.
Piece of fucking shit9 -
That would probably be implementing multithreading in shell scripts.
https://gitlab.com/netikras/bthread
The idea (though not the project itself) was born back when I still was a sysadmin. Maintaining 30k servers 24/7 was quite something for a team of merely ~14 people. That includes 1st line support as well.
So I built a script to automate most of my BAU chores. You could feed a list of servers - tens or hundreds or more - and execute the same action on each of them (actions could be custom or predefined in the list of templates). Neither Puppet nor Chef or Ansible or anything of sorts was consistently deployed in that zoo, not to mention the corp processes made use of those tools even a slower approach than the manual one, so I needed my own solution.
The problem was the timing. I needed all those commands to execute on all the servers. However, as you might expect, some servers could be frozen, others could be in DMZ, some could be long decommed (and not removed from the listings), etc. And these buggars would cause my solution to freeze for longer than I'd like. Not to mention that running something like `sar -q 1 10` on 200 servers is quite time-consuming itself :)
And how do I get that output neatly and consistently (not something you'd easily get with moving the task to a background with '&'. And even with that you would not know when are all the iterations complete!)?
So many challenges...
I started building the threading solution that would
- execute all the tasks in parallel
- do not write anything to disks
- assign a title to each of the tasks
- wait for all the tasks to complete in either
> the same sequence as started
> as soon as the task finishes
- keep track of each task's
> return code
> output
> command
> sequence ID
> title
- execute post-finish actions (e.g. print to the console) for each of the tasks -- all the tracked properties are to be accessible by the post-finish actions.
The biggest challenges were:
a) how do I collect all that output without trashing my filesystems?
b) how do I synchronize all those tasks
c) how do I make the inception possible (threads creating threads that create their own threads and so on).
Took me some time, but I finally got there and created the libbthread library. It utilizes file descriptors, subshells and some piping magic to concentrate the output while keeping track of all the tasks' properties. I now use it extensively in my new tools - the ones where I can't use already existing tools and can't use higher-level languages.4 -
Doing linguistic research where I need to parse 2000 files of a total of 36 GB. Since we are using python the first thing I thought was to implement multi threading. Now I changed the total runtime from three days to like one day and a half. But then when I checked the activity monitor I saw only 20 percent of the CPU usage. After a searching process I started to understand how multi threading and multi processing works. Moral of the story: if you want to ping a website till they block you or do easy tasks that will not use up all power of one core, do multi thrading. If you need to do something complicated that can easily consume all the powers of a single CPU core, split up the work and do multi processing. In my case, when I tried to grab information from a website, I did multi thrading since the work is easy and I really wanted to pin the website 16 times simultaneously but only have 4 cores. But when it come to text processing which a single file will take 80 percent of cpu, split it up and do multi processing.
This is just a post for those who are confused with when to use which.12 -
Trying to run a process on each CPU thread in our vps only to find that our vps has just one CPU and no multi threading. :/
We need an upgrade.1 -
Oh boy some mutex deadlocks inside the 16 year old, unmaintained, company application framework.
Time to look at the stack traces of 24 different threads and try and guess which one fucks it up
(Send help)5 -
<just got out of this meeting>
Mgr: “Can we log the messages coming from the services?”
Me: “Absolutely, but it could be a lot of network traffic and create a lot of noise. I’m not sure if our current logging infrastructure is the right fit for this.”
Senior Dev: “We could use Log4Net. That will take care of the logging.”
Mgr: “Log4Net?…Yea…I’ve heard of it…Great, make it happen.”
Me: “Um…Log4Net is just the client library, I’m talking about the back-end, where the data is logged. For this issue, we want to make sure the data we’re logging is as concise as possible. We don’t want to cause a bottleneck inside the service logging informational messages.”
Mgr: “Oh, no, absolutely not, but I don’t know the right answer, which is why I’ll let you two figure it out.”
Senior Dev: “Log4Net will take care of any threading issues we have with logging. It’ll work.”
Me: “Um..I’m sure…but we need to figure out what we need to log before we decide how we’re logging it.”
Senior Dev: “Yea, but if we log to SQL database, it will scale just fine.”
Mgr: “A SQL database? For logging? That seems excessive.”
Senior Dev: “No, not really. Log4Net takes care of all the details.”
Me: “That’s not going to happen. We’re not going to set up an entire sql database infrastructure to log data.”
Senior Dev: “Yea…probably right. We could use ElasticSearch or even Redis. Those are lightweight.”
Mgr: “Oh..yea…I’ve heard good things about Redis.”
Senior Dev: “Yea, and it runs on Linux and Linux is free.”
Mgr: “I like free, but I’m late for another meeting…you guys figure it out and let me know.”
<mgr leaves>
Me: “So..Linux…um…know anything about administrating Redis on Linux?”
Senior Dev: ”Oh no…not a clue.”
It was all I could do from doing physical harm to another human being.
I really hate people playing buzzword bingo with projects I’m responsible for.
Only good piece is he’s not changing any of the code.3 -
When I was about 10 I tried to make a basic midi sequencer/synthesiser using just the python standard library.
The only sound production there was was winsound.beep, which played a sine wave at the frequency given.
I realised that if I put enough really short beeps together I could make some mildly convincing instruments - I remember an electric piano, acoustic guitar, some kind of bass synth, and maybe more?
Then I put them together to make a song. The problem was though that you can't play multiple notes together as winsound.beep was blocking (though I didn't understand that at the time).
I had no knowledge of threading or async so I opened multiple python interpreter instances to play multiple channels. That's how I learnt about command-line arguments!
But I really struggled to get the sounds to be in time because python is not exactly rapid.
I made a kind of note sequencer using a library called easygui, based on tkinter (TCL wrapper), and I remember being told off at school for bringing in a usb stick with the exe of my program that I made with py2exe.
So many old technologies and fond memories...2 -
There's a lil tool someone wrote that runs as a post build event for one of our projects. I got bored of watching that tool hog a single CPU thread for like half a minute each time I had to build, so I tried making the thing multi-threaded...
...and it worked! Shit runs on all threads for just a few seconds now 💪🏻7 -
Hell World
So to followup with the enterprise grade goodness, I made a little prototype~
https://github.com/EnterpriseSoftwa...
Not very enterprise like yet, but a fun first 'extension' to writing a proper hello world program.
Ideas
--------
*Things that might make it more business like*
- Lots and lots of abstraction
- Tests ( not very business like but more stuff = better )
- FFI | Shared library, because why not
- Threading / workers
Hardcore:
Design a dedicated language for writing hello world programs that is compiled / interpreted on a simulated custom hello-world-cpu and displays it's content on a simulated screen.
Note
--------
I want to keep the documentation & code normal / actually helpful as a contrast to the concept itself and of course to keep my sanity.24 -
Dear everyone who doesn't write JS and has some hand-wringing concern about its lack of static typing, lack of threading, or its suitability for large back-end services:
It's fine, we've got this. You go back to discussing contravariance or whatever it is you do.
Signed,
Team JS4 -
Yeaaahhh that moment when the program flawlessly crunches through ten thousands of files, only limited by the slowish HDD! :-)
In full multi-threading, tons of dynamic buffer resizing, pointer shit left and right, also two star programming, and everything written in raw C!14 -
Best:
Really getting into Rust. It has taught me so many things.
1. Null is evil
2. Sum types are amazing
3. Compiler can actually have good error output
4. Multi threading is actually really scary if you don't have a compiler to back you up
Worst:
I had to deal with SSIS. It has also taught me many things:
1. No matter how 'mature' a product is, it can be awful. Simply dump a random error code, the user can figure out what went wrong, no need for good error messages.
2. The modern concept of the database is crap. It's a gigantic global state that is used by everyone and owned by no one.
3. Don't use tools that aren't made to be used with version control.
4. Even when you tell your team that it's bad, you will be ignored. -
Wanted to do a 1 hour coding challenge. Thought "hey why not use js this time". 3 hours later, my blood pressure is skyrocketing and i am really bothered by js threading.2
-
Prior to a tech conference in Las Vegas, the department manager held pre-meetings (yes, more than one)
with the developers to outline their expected behavior (yes, there was an outline in Word). Since
they would be representing the company, professionalism would be expected at all times, not just
during the conference. He knew he couldn’t forbid gambling and drinking, but any unruly behavior
that could reflect badly on the company would be dealt with severe disciplinary action up to and
including termination. He wrote up very detailed itinerary, what track each developer was
expected to attend, meal times (yes, what time to get up for breakfast, meet for lunch, and time
to eat at night). First day was fine, casinos are kinda crazy so having an itinerary wasn’t the
worst idea and no one got lost. Days following however, got interesting. After the first evening
meal, everyone hit the casino as expected (too much drinking, etc..normal single twenty-something
guys do) and the manager especially had a good time.
Next, and following days, the manager could not be found in any of the ‘required’ technical tracks.
Not that they cared that much, but couple of devs decided to check out the casino, and sure enough,
there he was at one of the tables, drunk, and being very loud around at 10 in the morning.
Again, nobody cared much, manager wasn’t very tech savy, and so attending a track on C #threading
would be lost on him. It was more of ‘do as I say, not as I do’ kind of thing.
The manager kept to the itinerary, he met everyone at breakfast, lunch, and dinner, etc, but the
‘WTF’s didn’t get good until the manager was bragging about how wonderful the conference was, how
much he was learning and couldn’t wait to get back and start implementing everything he was learning.
It was such a joke, the guys would bait him on tracks they know he didn’t attend and an amazing amount
of BS could not be believed.
On the last day of the conference several decided to follow him after breakfast to see where he went
and watched him go into a technical track, just to walk back out and straight to the casino floor.
Again, around 10, he was drunk, not quite as loud until he threw up in a trash can (they said it was quite a scene).
He left to go back his room, which they suspected he took a nap before meeting everyone for lunch.
After that, they gathered his daily itinerary was:
- Get up for breakfast
- walk around and make sure it looked like he was heading to a track
- head to the casino
- take a nap
- eat lunch
- walk around some more
- head to the casino
- take a nap
- eat dinner
- head to the casino
- wash-rinse-repeat
Last day caught up with him. After about week of drinking, staying up late, etc, his body (he’s in his mid 50’s, 350lbs+, so imagine)
kinda’ gave up. Could barely walk 50 feet without needing to sit down, and the flight back was worse for everyone,
throwing up occasionally, moaning, you get the idea.
On the following Monday with the VP if IT, everyone was discussing the conference, what they learned,
what they liked, etc, the manager also bragged, yes bragged, on how tired he was because of how much
he learned and the reason why he probably caught the flu (he couldn’t hide how sick he was on the flight)
saying “When you’re in the learning zone, you lose track of time and then you are so exhausted, your
immune system is susceptible to all kinds of things.” . VP was so impressed by his dedication and
fighting through the exhaustion for the good of the company, he gave him the rest of the day off.
Other devs? No, they had to go back to work.9 -
Can someone help me understand?
I subscribed to a nifty IT-releated magazine, and on its back, there's an ad for "Dedicated root server hosting", nothing unusual at a first glance, but after I read the issue, I decided to humor them and see what it is that they offered, and... It just... Doesn't make sense to me!
An ad for "Dedicated Root Server" - What is a dedicated root server first of all? Root servers of any infrastructure sound pretty important.
But, the ad also boasts "High speed performance with the new Intel Core i9-9900K octa-core processor", that's the first weird thing.
Why would anyone responsible enough want to put an i9 into a highly-reliable root server, when the thing doesn't even support ECC? Also, come on, octa-core isn't much, I deal with servers that have anywhere between 2 and 24 cores. 8 isn't exactly a win, even if it has a higher per-core clock.
Oh, also, further down the ad has a list of, seeming, advantages/specs of the servers, they proclaim that the CPU "incl. Hyper-Threading-Technology"... Isn't that... Standard when it comes to servers? I have never seen a server without hyperthreading so far at my job.
"64 GBs of DDR4 RAM" - Fair enough, 64 gigs is a good amount, but... Again, its not ECC, something I would never put into a server.
"2 x 8 TB SATA Enterprise Hard Drive 7200 rpm" - Heh, "enterprise hard drive", another cheap marketing word, would impress me more if they mentioned an actual brand/model, but I'll bite, and say that at least the 7200 rpm is better than I expected.
"100 GBs of Backup Space" - That's... Really, really little. I've dealt with clients who's single database backup is larger than that. Especially with 2x8 TB HDD (Even accounting for software raids on top)
This one cracks me up - "Traffic unlimited"
Whaaaat?! You are not gonna give me a limit to the total transferred traffic to the internet for my server in your data center? Oh, how generous of you, only, the other case would make the server just an expensive paperweight! I thought this ad was for semi-professionals at least, so why mention traffic, and not bandwidth, the thing that matters much more when it comes to servers? How big of a bandwidth do I get? Don't tell me you use dialup for your "Dedicated Root Server"s!
"Location Germany or Finland" - Fair enough, geolocation can matter when it comes to latency.
"No minimum contract" - Oooh, how kiiiind of you, again, you are not gonna charge me extra for using the server only as long as I pay? How nice!
"Setup Fee £60" - I guess, fair enough, the server is not gonna set itself up, only...
The whole ad is for "monthly from £55.50", that's quite the large fee for setup.
Oh, and a cherry on top, the tiny print on the bottom mentions: "All prices exclude VAT and are a subject to..." blah blah blah.
Really? I thought that this sort of almost customer deceipt is present only in the common people's sphere!
I must say, there's being unimpressed, and then... There's this. Why, just... Why? Anyone understands this? Because I don't...12 -
Fuck this shitty C ecosystem! Multible compilers, one standard complying, one hacked toghether? Only one GPL poisoned standart library, with no real chance of switching it, which prevents me of making staticly linked programs? And then there is microsofts compiler, with fucking ANSI support. Thanks. No dependency handling. Concurrency? pthreads. Are you fucking kidding. JSON? Have fun finding something static. Compile times where you can read entire books. Segfaults without one helpful info, so you have to debug with prints. And every library, every tool, installer, compiler, stdlib, anything is poisoned by GPL. But hey, its fast. And efficient. After you spend many slow and inefficient months developing something. I am so done with this shit.
Well.
Tommorow i will continue working with C on my backup project.
Did i mention that the stdlib has no features? Not even threading? Which is IN THE STANDARD?8 -
The fact that the sleep function is in the time module and not in, like, the threading module is so stupid.7
-
<opinion>
You may be a prod ninja but I believe that every dev should have a decent level of exposure with a low level language(s). Sure you can make an HTTP server, do a sentimental analysis, topic modeling, set up multinode clusters, write ORM queries from dbs and all sorts of awesome stuffs with Python/Ruby/PHP/JS/GO etc but none of them teaches you what happens at kernel level. Things like memory leaks, threading, multiprocessing, memory allocations etc can only be better learnt from a low level language.
</opinion>
P.S. Not a C/C++ fanboy. I'm a python dev 😄5 -
I am reviewing a piece of code as I type this, and I just had to make a rant about it. In the code there's all these measures for syncing multiple threads, while the entire thing runs does not even use threading. But that's not the worst: when an InterruptedException is caught, is calls Platform.exit() WHICH CLOSES THE FUCKING PROGRAM. WHY WOULD YOU EVER DO THAT?1
-
** this means words are muted **
Friday:
I send a mail the client a Google doc with elaborate details about evaluation of an Android tablet from a Chinese manufacturer.
Monday:
The client is upset, he says "You say there is no GPS chip on the tablet while the manufacturer says otherwise"
Me- "I have clearly mentioned that it has a GPS chip"
Client- Opens the Google doc, points to a sentence. Looks at me like I did something horrible.
Me - **This guys is either word blind or something else is wrong with him, the line reads 'GPS chip available'**
Me- "Look, it says 'GPS chip available'.
Client- **Blinks n blinks again** "Alright, but why did you share a Google document, why not PDF, docx"
Me-**Politely** "You can download the document in any format, look I will show you..."
Client- "It should have been in the mail itself ideally"
Me- **WTH** "We normally maintain a document for such things to keep everything organised, but if you want I will put everything in mail itself"
Client- "Hmm.. do both from next time"
Me- "Alright" **BS**
Client- "Why is the new feature taking so much time"
Me- "As planned earlier, we going to deliver it tomorrow"
Client- "Why not today??" **Gives a strange look.**
Me thinking - **Enough**
Me- "See, I am trying to integrate a smarten with a socket connection, reading it's data via exposed APIs that are hardly documented, we need faster performance so I need to implement caching, multi threading, offline handling, multiple processes to avoid memory fluctuations, sync adapter to sync data...."
Client- "Ok ok ok, it's fine if you give working build tomorrow"
Me- "Ok, fine"
#limit1 -
It's always so funny when a person starts using multiprocessing in Python, because if there's "multi", obviously THIS is the thing that should free the person from a headache of having GUI frozen. You know, because it does "multiple" ehm... stuff..... at once....... yeah. And it's popular, it must work for me too! Oh how often I see this. :D
Stupidly enough that's not entirely a user's fault, but Python's as naming things with "multi" doesn't end up well basically with anything. I bet if there was such thing as multipointer in C half of the beginners would be totally fucked and the other one would just break their machines beyond repair with a joy.
Yet... reading the damn documentation should be a requirement before using threading or multiprocessing to prevent the confusion, because there's this funny difference between multiple threads and multiple processes which will haunt you unless you see what's what and use it correctly.2 -
Thinking about including a file that is named: pleasedontdelete.cpp into the codebase. Don't include it in the project and put vague references to things in the code. Put variables that could be misconstrued as being related to bitcoin or some other cryptocoin. Put lots of comments saying: experimental.
Got a weird growth on my finger. Tried cutting if off with a razor blade. Now it is a stinging bleeding growth. Is not getting bigger. Just seems like a weird callous.
Found out gdscript has threading. Now I understand why Godot went away from Python. They actually wanting to do shit like threading. Every time I look into the gdscript library I find new gems. I mean it has a xml stuff in there. Found that today too.
Probably going to make a simple custom editor for a game I have been playing. I built a prototype a few years back on a weekend. Played the game again and now want it. I originally used Qt and C++. I think I will now try to make it in Godot.
I have been moved around the building as they move offices around. Now back upstairs instead of downstairs. Currently alone in a huge room that had cubicles. I am the only cube left. It feels like Davy Crocket at the Alamo. YOU WILL NEVER TAKE ME ALIVE!3 -
Lord. Please deliver us from the cycle of unfinished programming languages and code benches that are designed to create more work for us. We beseech thee in thy mercy to transmute all this asynchronous lead that is found in javascript into a purer form of threading that is sensible and can be willfully blocked or not so in a way that works and does not divide us through our ugly code. May also we be given the ability to purge from our midst all child molesters and string them up by barbed wire off a line of telephone poles across the entire continental usa and may there be a sudden increase in the number of ravens and buzzards to feed on them, being nice birdies that I miss seeing so much. May half their positively identified population be kept alive and delivered unto us that we might remove their scrotum with a hook-ed barb and something resembling a serrated metallic spork, amen.
and please fix fucking node js. i agree that its asynchronous methods suck ass for literally everything as there is no use for it that seems to work given its a shitty emulated single thread.2 -
Presented my project at uni, teacher was pretty pleased and I'll get my grade some time next week, but for those that are interested, here's a small video of it in aciton:
https://youtu.be/LYV3bIC6QmU
Uses: Raspberry Pi 3B, Mifare RC522 RFID reader, a breadboard, ribbon cable, neopixel rgb led ring and a TowerPro sg90
For the ui I used PyQt5, almost got the threading completely working, there's only 1 blocking thing left, that's when the message for logging in doesn't disappear -
Currently making a perfect sudoku webapp / plugin using native JS and html templates where I'm very enthousiast about.
It allows to select multiple cells and then put in a number and all selected have that number. It keeps state of every change, you can do unlimited redo's. Right click or double click someehere removes selection. Not built yet, but it will have a box where you can paste sudoku's you've found on the internet. I just parse 81 times [1-9] with regex. So all formats are supported including noisy ones as long the noise is not numbers. Making your own puzzle is very easy. Art is to make hard ones. I'm generating extra hard puzzles using C threading. For reference: there are 6,670,903,752,021,072,936,960 sudoku puzzles possible and from that I try to resolve the hard ones using simple human logging with brute forcing as fallback until it can use logic again. 30 million attempts to solve per secon. I should at some more logic. I don't do xwing or ywing, bs imho. You have to be a superhuman to spot xwing / ywing possibilities. I think i can imagine a better logic myself. We'll see.
And yes, that's a real screenshot. Puzzle is validated and it found issues. Marked with red font. Green is current selection by user11 -
Multi-rant incoming!
1.
Stereotyping.
When did that shit become the norm?
2.
I'm lost in ROS smach. Does anyone do multi-threading in ROS services, or should I flip a table on smach? 😒11 -
One responsibility of our team is general code QA for the entire dev department, DevMgr walks in our area yesterday…
DevMgr: “Has anyone reviewed the new WPF threaded model execution code?”
- everyone on the team responds “no”
DevMgr: “Can we get a review on that code ASAP? If it works as well as the developer said, it’s going to solve the lock up problems users are experiencing and automatic logging of errors.”
DevA: “Well, no amount of code is going to stop users from performing bad searches locking up the user-interface. That code is just a band-aid around the real problem. If the developers would write unit tests first …”
- rant about 5 minutes on unit testing that had nothing to do with why the DevMgr was here
DevB: “Yea, the code probably isn’t written to handle threads correctly. All the threading they’ve done so far is –bleep-”
DevMgr: “Oh, I wasn’t aware of that. Get me the results of the code review and if they don’t have unit tests, delete it from source control and let the developer know it’s not up to our standards.”
OMFG!! You have not even seen the code!
OK, DevA ..what the –bleep- does unit testing have anything to do with the user interface! You know the DevMgr is too dim to understand the separation of concerns. Shut your pompous ‘know-it-all’ mouth.
DevB…what the –bleep- have ever done in WPF? You manage the source control and haven’t written any C# in two years and never, ever written code for any significant project. Take that “handle threads correctly” and shove it up your –bleep-. Pompous –bleep-hole. Go back and watch youtube and read your twitter while the grown-ups get the work done.3 -
Hi people first as you know my English is not very poor im sorry for that.
I try to make an automat a sprinkle water and a auto light on a interior garden in aquarium.
For that in python i use main thread, a class Water.py extends Threading and Light.py extends Threading
In the __init__.py file i put my main function that get argv for execution. One of my arguments is -v (--verbose)
I want to pass that args to my class instances.
-I don't want to make one parameter in my constructors because I think we don't passe verbose mode in parameter of constructor.
-I use global not working through de import.
Do you have some magic for me :/ ?6 -
Just got made regular at my current employer, but the last month or so I've been threading the needle on whether or not to take it (unfortunately, financial woes made the decision for me, but I digress). Thing is the company culture rewards dishonesty and is slightly toxic with middling managers, even if the work is good.
That said, given the circumstances above, how long would you consider it reasonable to stay at such a company before resigning or interviewing for a new job? Give it a year, or six months, or wait for a dealbreaker like a delayed paycheck?
I don't want to be a jerk just because I work for jerks, but the lack of positive change in our workplace is just demoralizing. Being offshore as well doesn't make it easier.3 -
Okay so I have a stressball, but the kind of fucked up stress I was in the last two days required more than just my stressball.. I Okay so I have a stressball, but the kind of fucked up stress I was in the last two days required more than just my stressball.. I really need a punching bag..
FUCK!!
EDIT:
I'm not only feeling stressed, but I also have A LOT of anger inside me.2 -
I have 1000 problems and
Reached here
Function called
#############
and threading
While loop
Blah blah blah
Blah Blah blah
Is one of them
==================
lololololololololololololo
I hate threading
5555555555555555555
Shitshitshitshitshitshitshit6 -
When some colleague ask for help in a project that you're supposed to know everything but you really don't (damn multi threading in Java )4
-
!rant
Julia's mutlithreading macro is soooo awesome and clean for when you want to do computation work :33 -
I hate those "simple DIY" instructables. Just had to build something I had to get. Found out one "simple DIY". It requires owning a power drill with a table mount. And a pipe threading machine. Yes, I surely have a drill mount for drilling thru some steel, I know how to use a CNC machine, and maybe have a little metal foundry in my flat. But hey, it's a DIY not 'go to nearest store and buy that friggin piece you need' so you should have prepared yourself for some difficulties.
It's not supposed to be easy!
I still wonder why the author not assumed everyone own a metal foundry, after all. It would be much easier for all of us.
And I ended using PCV, glue, and a spare bottle. Had to buy drill for glass, less than $3. Wasted few bottles to cut out what I wanted. Beer was quite good, thou.1 -
I wrote a simple Python script to split a Wikipedia page into manageable chunks. But it took a while to load, so I decided to add a loading indicator. Just a few dots appearing and disappearing. How hard could it be?
"Okay, so I just need a few dots as a loading thing."
"Right, so I suppose I'll need a separate thread for this... Better look up Python's threading again"
"So the thread is working, but it keeps printing it out on separate lines"
"Right, that should fix it ... nope."
"I should probably fix the horrible mess here"
"Hmm... maybe if I replace the weird print() calls with all those extra parameters with sys.stdout.write()..."
"Right, that kind of works, but now there's just a permanent row of dots"
"Okay, that's fixed... Ish."
Well, it works now, but there's a weird mess of two \r's and a somewhat odd loop. Oh, and there's more code for the loading indicator than for the actual functionality. This is CLI by the way.7 -
When I was on my first internship, I started developing an Android app, while my friend developed a C# program that read a .txt with info and references from a mail service (in my country it's CTT).
The damn .txt files got really really big, na she had to display all of the data in a listbox (it was a PoC) and when he pressed the item, it had to fill some fields at the left of the listbox.
Needless to say, he didn't learn of multi-threading yet, and I had, so I taught him how to multithread so the app wouldn't lock up while loading the massive .txt file.
The listbox filling made a cool animation (like CMD executing commands from a bat file) and we even implemented a progressbar.
I felt like a badass Dev after that. -
A third party jar did nit support multi threading in our project. After the module was multi threaded it got stuck after few runs.
I felt like superman after finding the bug.1 -
I just created a wolpertinger.
https://en.m.wikipedia.org/wiki/...
We have the problem that the number one build tool for scala / java is sbt.
Sbt sucks.
There are many nice plugins for maven.
Sbt can generate a POM from an SBT build.
But the plugins need to be set up, so the generated POM must be modified...
... a POM is XML.
So Python, Pexpect (as SBT needs a PTY and is very cranky regarding exiting properly and running non interactive)… POM XML modification....
Maven - Plugin run.
But we need to do this on... Larger scale.
So, as I'm a lazy mofo, I wrapped the python thingy in bash, mostly because it was simpler than dealing with async / threading in python. Just spawning per project...
So we have Bash, Python, Java, SBT / Maven, hand in hand....
... Is it normal to feel sorry for the build server?1 -
Threading, asynchronous events and scheduling...
My straight jacket feels welcoming, and I take comfort knowing that before I put it on, I got the code working. -
So funny thing happen yesterday night. I was attending a small talk at a meeting here in our town where one guy had to present some unconventional "React" methods and the other one had to present "ClosureScript".
The "React" guy didn't show up, and the "Closure" guy told us that this compiler is multi-threading but in fact by his examples was single-threading.
So instead of learning new stuff in there I just laugh my ass off because of this event. -
I'm still on a regular basis reminded of how I might be wrong despite the absolute certainty in how obviously wrong the other person is.
Lately I've been working on setting up this API with a fairly intricate database integration. One request can lead to multiple db calls if we're not careful, so we have been polishing up the implementation to guard against ddosing ourselves and dealing with thread-unsafe concurrency.
Someone on the team could happily report that they got rid of all async use so there should no longer be threading issues. "You mean it all runs sync now?" "I guess. It works at least".
I'm just internally pulling a surrender cobra. If this was pre-dev me I would have let him and everyone know what a stupidpants he is and that I thought he had some experience in api development. But let's not make an exception to the rule; I might be wrong. I mean I'm not, but let's pretend I could be. Let's pull down the changes and maybe set up a minimal example to demonstrate how this is a bad idea.
Funny story. He got rid of explicit calls to the database entirely. When resolving data, the query is instead constructed virtually and execution is deferred until the last step. Our functions are sync now because they don't call the database, and threading isn't an issue since there's only one call per request context.
Thank god I've learned to keep my mouth shut until I can prove with absolute conclusive certainty that they are wrong. Here's to another day of not making an ass of myself. -
wrote dumb threading and sockets system to make a bunch of https calls
extracted the working code into nice objects and methods to make it look sane and so I can re-use the code for more complex functionality that builds on itself
now suddenly the threads are locking and not multi-threading anymore
turns out?
the http(s) library expects the tls / https thing in an Arc / atomic reference count
but despite Arc being literally intended and designed for threadwork it seems the library in question throttles / locks itself if they are all using the same Arc (I don't even know how that is possible?)
if I clone the tls / https thing, no throttle / lock issues 😒
why did they even try that lol, they didn't test?!
I really didn't expect to be better at multi-threading than others already. I'm newbie. pls6 -
Threading gui's and sockets...
What a painful day...
I honestly hate python dependency hell.
Started coding in python 2 months back, currently working on a distributed alarm system using rpi3's spent the whole day figuring out how to use it all without them all crashing into one another...1 -
Programmer looking for a new language
I have been a JavaScript developer for a few years now (non professionally) and I really like the language. I mainly program for execution with NodeJS rather than web, because I feel like I get more freedom (e.i. the ability to use a computer file system).
I normally never use other people's libraries and instead either write my own library/ies for the specific task or use an old one. I only ever use someone else’s if I need a quick frame work to test an idea, never for something I will actually use.
I prefer to work object / class orientated.
I have worked on distributed servers with NodeJS before, however trying to distribute a load across one computer across it's multiple threads has proved problematic due to the heavy delays of standard io transfer speeds.
Why do I want to switch?:
•Because JavaScript is not at all created with multithreading in mind, and pretty much any multithreading solution is a bodge and allot of the time it is more efficient to work single threaded.
•Also, I get the sense that JavaScript + NodeJS is not used often in the programming industry comparison to other languages like; ruby, python, and I don't want to get stuck in a nesh language of which would decrease my employment chances heavy.
Side Note: I have been working on a pet project to have a distributed database (made with nodejs), and so far, there are no language specific problems, but I feel like it would be more efficient if I used a programming language designed more to cater for multi threading.5 -
Week 1 day 3 and 4.
I didn't feel like I did a whole lot yesterday so I just pushed it into today. In the past I tried to program for hours everyday and expect to keep up my stamina for it but it didn't work so this time I'll just take days off every now and then and see if that works at all. Yesterday was one of those, the only thing I did was watch some videos on OOP and practice some more with OOP and recursion.
As far as today goes I started sketching our the ideas for my own personal app I hope to develop once I get the skill set. I tried to focus on looking at it not just from the perspective of a developer but also a user and a marketer to see vialibity and such but I have a LONG time to go before I can get my idea rolling. I decided to push starting the actual course until tomorrow because Ina small questionnaire before you go into it it asks if you're familliar with threading and networking, which I am not. So that was my main focus today, expanding my base Java skill set. If any Android Devs can give from their experience want I need to know I would love that but other than that I feel pretty good about what I did today. -
Oh for fucks sake! Why so we have threading when we synchronize EVERYTHING with a singleton... and when I actually show you that even unthreaded spaghetti code runs 40% faster under real life conditions than your shit you just brush it of because I'm still at university and don't know what I'm talking about... And not because changing it would require money or time we don't have... no, just because I “lack the necessary experience with such things.“
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Hey guys I've a problem I've been trying to solve for a while. Also I'm a college student so my knowledge isn't going to be the greatest so go easy on me if it's simple to solve😂. So I'm creating a real time licence plate detector using yolo lite, my own deep learning ocr and plan to add the model to fast api. So as an input to the rest api, the user will submit a IP camera link for openCV to get individual frames for preprocessing before yolo predictions. The problem I have is how to I handle multiple real time IP camera feeds at once?. Ive been researching multi threading but read that it can cause issues with async definitions in fast api. Any advice will be greatly appreciated and if more information is needed just shout!.
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Is it possible to record the time a thread spends processing only it's code?
E.g. capture sys.ms in thread A -> A is sliced and thread B runs -> B is sliced -> A comes back and captures current sys.ms. The resulting delta of Anow - Ainit includes the time that B spent on the machine.
Is it possible to account for this and get just the time A spent processing?
Is this doable on any other languages?
If it is or isn't, any documentation or papers explain why is appreciated. Google is flooded with "how to time" questions so I'm not seeing any answer for this.7 -
Ive been running a brute force program on kali linux virtual machine which was using multi threading by sending Hundreds of requests per 10 seconds 24/7 my laptop overheated and shut down and now my kali linux vm wont boot up something got broken heres a screenshot help please17
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python's threading is like cake. you eat one piece, then it eats the rest, and if you want the rest, you gotta convince it to vomit it out by doing absurd code. Then once it vomits it out, its still bad. So in the end, you can never win :p4
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I have to change the model of my application but I don’t like the way it was written because it was written with multi threading in mind which I don’t mind using and It makes sense to use but now Idk how I can make any changes.
And I don’t even know where the fuck to start
Also it relies on a lot of OOP stuff and it annoys me. (I don’t really enjoy OOP)9 -
Python3's asyncio is awesome.
In an IoT server we used python2 socket programming with multi-threading. Recently I have changed the socket layer to python 3 asyncio and performance was far better. I am not gonna use multi-threading anymore.
What do you guys think about asyncio?1 -
I have an app I have developed that uses concurrency. My dev env allows me to select different targets. One of those targets is WebAssembly. So I got it configured and decided to test my app. It immediately failed on compile due to the concurrency module missing. I later found that for my dev env concurrency for webassembly is experimental.
So concurrency is a thing for webassembly, but the support on my dev env end is not there yet.
Is threading difficult in webassembly?2 -
Hello, I have a question for anyone familiar with multithreading!
I just started working with threading for the first time, I mostly write powershell scripts 😅, I found that certain conditions make using multithreading an absolute time saver. And of course in some tasks it's not such a big deal.
I am currently working on a project that runs multiple threads and each thread might invoke one of my functions that also threads the work.
I'm a total newbhat when it comes to this stuff, but if my main process is 4 threads, and I can spin up, up-to 4 more threads to run one of my functions, does the math equate to a possible total number of threads of 16 or is it possible to have the threading go ape-shit bananas and utterly thrash the cpu with rampant threads getting created?
I've looked online and based on some of the info that I've managed to come across on my own, the answers elude towards being safe because I'm creating pools for running the threads first and the pool is responsible for maintaining min/max threads, but I can't seem to find good info on running a pool+threads inside another thread.
Just to let you in on what the function does that requires threading in the first place, I need to basically query CloudTrail based on ARN's to find events, but I can only pass a single ARN to the find-ctevent cmdlet. So I'm essentially making 1500-ish really really small calls to AWS just to get back event data for the ARN.
Serially, this takes like almost 20 mins, on my laptop using stupid settings like 24 threads, it completes in about 95seconds. On the actual server that will be running this code, I'm going to limit it to 4 threads and try to figure out a way to cache the info locally and update the info on a cron or schedule so only the initial scrape takes forever and then the updates can be done nightly or something.
thank you in advance for your help, I'm not too sure if the question is dumb but please let me know either way!8 -
I love ruby, except the official implementation is super slow and bad at multi threading. But that's where Jruby comes in :)
(Still relatively slow though :( ) -
Yeah... I spent way too much fucking time thinking my multi threading was fucked up. When in actuality I had a parameter in a JSON payload for an API call I neglected to check for changes.
A fucking form id! Just one parameter had me frustrated for 2 hours.1 -
Ugh, have an assignment due and just spend the last 2 hours looking for a bug that caused blocking code in one of socket threads.
Looks like it's going to be a long night -
Been looking into some of my old code (an OBSE plugin). Wanted to know how something worked I made over 10 years ago. I look through the code and some of it makes sense, some of it looks really messy compared to what I write now. I want to remake some of this code to work on a different game now.
I have some code for threading that I have no idea where it came from:
https://github.com/Demolishun/...
It allows transferring data between different threads using mutexes. It is really really simple. I searched github to see if it came from there. There is stuff with similar names, but the code is way way different in those. I honestly don't see whey this code needs to be any more complicated than it is. I wonder if it is because I don't know something or I just like simpler solutions. Maybe there are use cases the other coding solutions have that solve particular problems?
Anyway, I plan to pound out an SKSE version of this plugin. I have been wanting to make this for some time now. I don't necessarily have a need other than the fun factor. My lack of providing good directions for use on the OBSE version kept people from using it. I will try and do better on this version.2 -
Hey, I need a little help here and I don't have a lot of time to figure this out.
I have this piece of code which I wrote in flask when I had just ventured into programming. The idea is that we have two excel sheets a search file and a demand file, all we need to do is search for the names from the demand file in the search file and then produce the result in an appropriate format. The problem, the names don't match up, quite often. Sometimes the spellings are wrong sometimes the way they named one things in the files is different, so, for that I have a keyword based search and I make another sheet called guesses where this data is then written.
I made it for my mom who's a doctor and does procurement (buying stuff) for the hospital. It was just a small project to help her and her team with a very inconvenient and boring task and I never could host it cause I really didn't know how to (in py) and I had used socketIO in flask along with threading and stuff. But now, shit has hit the fan as the software is suddenly in demand for obvious reasons.
Just help me host this thing somewhere. Thanks, link in comments.3 -
People experienced with java/ multi threading , can you tell me how you build a pausing mechanism for threads? Like, if my bg thread is supposed to count for 100 seconds, and i need a mechanism to :
A: start it,
B: stop it on its counting completion/ manually
C: pause its execution at a number on a button click
D: resume its counting from the same number on another button click
How would i do that?
SO Question link here: https://stackoverflow.com/questions...21 -
Working with nightly builds and concept tech is such a fucking hassle...
I'm currently working on a WebAssembly proof of concept where I need to generate a unique id, but since threading is currently not supported (rust and webassembly) I cant use half of the libraries currently out.
And the ones that does work... guess what... are not compatible with the nightly build of the compiler I'm using for Rust. Just fucking end me.
The legit only workaround I can find is to make a server request and get the unique id from there... piece of cunt software...I need a break 😑 -
few days back i created real life example of live lock in multi threading
... and the whole night i was dreaming like i would have created dead locks in my real life... and i couldn't find how to remove those dirty synchronized blocks -
One of my big gripes about PyQt5 in particular is lack of info, especially on advanced topics. This includes books. I found this on Amazon today:
Qt5 Python GUI Programming Cookbook: Building responsive and powerful cross-platform applications with PyQt https://amazon.com/dp/B079S4Q9T2/...
It was just published in July. I’m thinking I might buy the Kindle book.
On reviewer complained about lack of info on how to handle child dialogs (after fighting with child dialogs that had their own children and dialogs with threading and all that, I feel you, brother). But the 2 reviews it’s gotten look fairly positive.
I wonder how advanced the book gets. Going to read the sample later.4 -
When every class you write inherits from threading.Thread. It doesn't need use threading.... but meh, you never know....