Python multithreading 🧵

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  • Опубликовано: 28 авг 2024

Комментарии • 86

  • @BroCodez
    @BroCodez  3 года назад +40

    # ******************************************************
    # Python threading tutorial
    # ******************************************************
    # thread = a flow of execution. Like a separate order of instructions.
    # However each thread takes a turn running to achieve concurrency
    # GIL = (global interpreter lock),
    # allows only one thread to hold the control of the Python interpreter at any one time
    # cpu bound = program/task spends most of it's time waiting for internal events (CPU intensive)
    # use multiprocessing
    # io bound = program/task spends most of it's time waiting for external events (user input, web scraping)
    # use multithreading
    import threading
    import time
    def eat_breakfast():
    time.sleep(3)
    print("You eat breakfast")
    def drink_coffee():
    time.sleep(4)
    print("You drank coffee")
    def study():
    time.sleep(5)
    print("You finish studying")
    x = threading.Thread(target=eat_breakfast, args=())
    x.start()
    y = threading.Thread(target=drink_coffee, args=())
    y.start()
    z = threading.Thread(target=study, args=())
    z.start()
    x.join()
    y.join()
    z.join()
    print(threading.active_count())
    print(threading.enumerate())
    print(time.perf_counter())
    # ******************************************************

  • @blizni3371
    @blizni3371 2 года назад +38

    If you have problem with huge amount of time displaying by time.perf_counter() function here you have solve of this problem:
    We can read in documentation:
    time.perf_counter()
    [...] The reference point of the returned value is undefined, so that only the difference between the results of two calls is valid.
    So to solve it we have to declare variable before our code, for example:
    starting_point = time.perf_counter()
    ...
    our code here
    ...
    print (time.perf_counter() - starting_point)

    • @KudoShinichii1412
      @KudoShinichii1412 11 месяцев назад +3

      thank you I understood that , but I am really wondering why did not happen to him

    • @Mildic
      @Mildic 11 месяцев назад

      wow man thank you very much, i was looking at my code for like 10 minutes and couldnt figure it out

    • @NoPo1nt
      @NoPo1nt 11 месяцев назад

      came here just for this. thank you

    • @lukaskelber
      @lukaskelber 10 месяцев назад +1

      @@KudoShinichii1412 Same, does anyone know why Bro didn't have to subtract two perf counters? Is there maybe some setting for this?

    • @Dmitopur
      @Dmitopur 9 месяцев назад +1

      Thx! I think without your solution that function counted seconds from the point of my pc was turned on.

  • @AmmarAlIessa
    @AmmarAlIessa 2 года назад +6

    Really like how you go to the heart of the subject.. Concise and clear... Thanks..

  • @d1jn
    @d1jn 2 года назад +13

    I really like how you explain everything so simply and quickly. Keep it up man !

  • @thepragmatic6383
    @thepragmatic6383 Год назад +3

    Thank you for these clear and precise explanations.
    As I am new to Python, this becomes very practical for my learning.

  • @user-vr2si8on9f
    @user-vr2si8on9f Год назад +2

    This is brilliant .
    Excellent explanation !!!
    👏👏👏

  • @waynefrannedavis9305
    @waynefrannedavis9305 6 месяцев назад +1

    Interesting to see how Python addresses multi-processing and synchronization when compared to Elixir which is my go to language. At 75 years old, I am finally looking at object-orientation.

  • @entity5678
    @entity5678 2 года назад +1

    Such a wonderful explanation..

  • @samuellopez5155
    @samuellopez5155 2 года назад +1

    great explanation, loved the theory before the actual code

  • @piotrkopcewicz5227
    @piotrkopcewicz5227 Год назад +3

    dobrze rozkminione :) Dziekowa

  • @felixnyamongo
    @felixnyamongo 2 года назад +1

    Understood in one go. Good work bro

  • @SleepyAizawa69
    @SleepyAizawa69 Год назад +2

    Firstly thank you bro
    Secondly if you guys have problem with main thread not printing 4then you must delete the() for writting the function in x=threading.thread()

    • @baldwin9207
      @baldwin9207 Год назад

      i was wondering why mine was different. thx!

    • @autoauto2000
      @autoauto2000 7 месяцев назад

      @@baldwin9207but why, now it works

  • @infinitecrafterYT
    @infinitecrafterYT Год назад +2

    nice video bro

  • @giaxlab
    @giaxlab 2 года назад

    Super, finally i learn this argument! :) Nice work!!!

  • @lawrencedoliveiro9104
    @lawrencedoliveiro9104 2 года назад +1

    For I/O bound problems, it is better to use asyncio than threads. This gives less opportunity for race conditions and their consequent hard-to-reproduce bugs.

  • @ugurbayrak9869
    @ugurbayrak9869 2 года назад +1

    >>> Very consistent explanation :)
    >>> Could you please do this kind of tuts regarding python standart libr modules like Struct, OS, SubProcess and Select ?
    >>> Have a good time

  • @ilordepic
    @ilordepic 2 года назад

    hope the algorithm blesses your channel

  • @ilhamm1915
    @ilhamm1915 Год назад

    THAT IS ACTUALLY REALLY COOL NGL

  • @FabioRBelotto
    @FabioRBelotto Год назад

    I would like that you showed an example like this : you can eat and drink at same time, but you must finish such activities to study.

  • @aaroncatolico7550
    @aaroncatolico7550 2 года назад

    Even though you sound like 'Butthead' from 'Beavis & Butthead', I still love you 'Bro'. And thanks for your awesome tutorials. 👍🏻👍🏻

  • @VenkataChalaBhaskar
    @VenkataChalaBhaskar Год назад

    Excellent Explanation !!!

  • @aliforootani9348
    @aliforootani9348 2 года назад

    great explanation, thanks

  • @Johann.Liebert
    @Johann.Liebert Год назад

    so simply, thankss

  • @HussainAli-sb1dv
    @HussainAli-sb1dv 9 месяцев назад

    love u

  • @Daniel-cl6hj
    @Daniel-cl6hj 3 года назад +1

    breh.... this is so clear...

  • @gamerawesome8105
    @gamerawesome8105 2 года назад

    you sir are the best

  • @xcorpionxyed2078
    @xcorpionxyed2078 2 года назад +1

    Hey bro I've a problem.
    Whenever I write my own code (following the same procedure) it shows only 1 thread and takes allotted time, but when I copy the given description code it and paste it, shows the 4 threads
    Can't figure out why is it happening??

  • @rubenc4696
    @rubenc4696 3 месяца назад

    thakns

  • @kamlesht.j9366
    @kamlesht.j9366 Год назад

    brooo you da bestt!!

  • @lw9954
    @lw9954 2 года назад +1

    TY bro

  • @brianwake100
    @brianwake100 2 года назад

    Great video thanks

  • @BaminIce
    @BaminIce Месяц назад

    Print("Amazing")

  • @bekturasanbekov1979
    @bekturasanbekov1979 Год назад

    thx 4 vid br
    o!

  • @shuaibalghazali3405
    @shuaibalghazali3405 Год назад

    Thanks for this

  • @nirutg5130
    @nirutg5130 3 года назад

    Thank you very much

  • @EissaAlahdul
    @EissaAlahdul 2 года назад

    شكرا جزيلا

  • @RenovaLabs
    @RenovaLabs 4 месяца назад

    Bro, Do they only work with functions?

  • @locrilydian
    @locrilydian 2 года назад +4

    for some reason my main thread waits for the other 3 threads to finish before it executes the print functions. i wrote the exact same code he wrote. anyone have an idea?

    • @blizni3371
      @blizni3371 2 года назад +6

      Hello, you probably wrote parentheses when declaring - target=
      for example:
      x = threading.Thread(target=eat_breakfast(), args=())
      Remove this and let's check again :)

    • @stevemiller123
      @stevemiller123 2 года назад

      I have the exact same issue, did you resolve it? Even when copying and pasting the code from the description.
      It's behaving as if I joined all the threads even when I haven't. So when I actually write, x.join(), y.join(), z,join().. the behaver is the same.

    • @MrPsichoKid
      @MrPsichoKid Год назад +1

      @@blizni3371 jesus Christ, thanks man, i was in a hole for like 2 hourse before figuring out this!

    • @blizni3371
      @blizni3371 Год назад

      @@MrPsichoKid No problem!

    • @ligdjumvidja8294
      @ligdjumvidja8294 8 месяцев назад

      Thanks a lot my friend ! Iwas trying to figure out why my example was faulty @@blizni3371

  • @dolevdo
    @dolevdo 2 года назад

    amazing thank!s

  • @Sstevewong36
    @Sstevewong36 6 месяцев назад

    great

  • @beingzero7541
    @beingzero7541 2 года назад

    Wow!!!!!

  • @moisesherrera71
    @moisesherrera71 5 месяцев назад

    but what if a function returns a value, how should we write that so we have the function in a separate thread then main but we can capture the return value of the function

  • @charan2446
    @charan2446 2 года назад

    Bro.. 👏 Heads down.

  • @Amir_Plays_non_stop
    @Amir_Plays_non_stop 3 года назад

    Crystal Clear!

  • @SuperStarEevee
    @SuperStarEevee 2 года назад

    Thank you!

  • @philtoa334
    @philtoa334 3 года назад

    Nice.

  • @airexpertdrop
    @airexpertdrop 3 года назад

    oh yea its cool

  • @ahiamatagabriel5696
    @ahiamatagabriel5696 2 года назад

    thank youuu

  • @Pjnpm
    @Pjnpm 3 года назад +1

    Make a tutorial for flutter please beer is on me 🍺

  • @uuhju7004
    @uuhju7004 3 года назад

    nice

  • @gustavoaponte1814
    @gustavoaponte1814 Год назад

    meow~! uwu

  • @ClydeKilgore-df8hy
    @ClydeKilgore-df8hy 4 месяца назад

    Why do I get the following error after importing threading and attempting to use it? AttributeError: partially initialized module 'threading' has no attribute 'Thread' (most likely due to a circular import)
    same message when I use active_count()

  • @manuelvaal1257
    @manuelvaal1257 2 года назад +1

    My main tread is taking 734078.1110504 seconds to complete its task. what possibly could be the issue?

    • @hinter9907
      @hinter9907 2 года назад +2

      the solution:
      # add this line just before running x.start()
      start_time = time.perf_counter()
      # add these lines after z.join
      end_time = time.perf_counter()
      delta_time = end_time - start_time
      print(delta_time)

  • @autoauto2000
    @autoauto2000 7 месяцев назад

    does not work 4 me?? how to unlock gil in pycharm

  • @cinquecento1985
    @cinquecento1985 Год назад

    yeah.. multi threading in the morning.. sounds familiar. like brushing teeth while getting the pants on.. =)

  • @aiviral_
    @aiviral_ 2 года назад +1

    Hey I got this problem with Python showing 34568.4580 seconds while it only takes 3-4 seconds and it's not the only case in which this happens. Does anyone know how to display seconds correcty?

    • @wilsonsoeparman8574
      @wilsonsoeparman8574 2 года назад +1

      Yup, me too

    • @mittlope2723
      @mittlope2723 2 года назад

      just divide it with 10,000 and you will get 3.4 secs

    • @mm-fn9uj
      @mm-fn9uj 2 года назад

      somewhy i have 374690.9 seconds

    • @hinter9907
      @hinter9907 2 года назад

      the solution:
      # add this line just before running x.start()
      start_time = time.perf_counter()
      # add these lines after z.join
      end_time = time.perf_counter()
      delta_time = end_time - start_time
      print(delta_time)

  • @techboomers8935
    @techboomers8935 Год назад

    Kindly revealed your face , we want to sees a person who know every language exist in this world

  • @estudio7753
    @estudio7753 2 года назад

    ate

  • @reinkdesigns
    @reinkdesigns 2 года назад

    should i be concerned that when i run the same code as you i get "590447.4203372" returned from "print(time.perf_counter())"

    • @ramanuj_g
      @ramanuj_g Год назад

      check above comments as the answer is there above.... nothing to be concerned just u have to add start time and subtract it from end time

  • @ixmjk
    @ixmjk 3 года назад +3

    Thank you Bro
    i run the exact same code but for me the time.perf_counter() returns a really big value for time taken sth like 11929.1326382 but in reality it takes 5 to 6 seconds to run i search online for solutions but nothing came out.
    Any solutions?

    • @aiviral_
      @aiviral_ 2 года назад

      I got the same issue :\

    • @wilsonsoeparman8574
      @wilsonsoeparman8574 2 года назад

      Me too

    • @lawrencedoliveiro9104
      @lawrencedoliveiro9104 2 года назад

      Are you taking the difference between values? Because the zero point is implementation-defined.

    • @nakiros24
      @nakiros24 2 года назад +3

      this worked for me:
      import threading
      import time
      def eat_breakfast():
      time.sleep(3)
      print("You eat breakfast")
      def drink_coffee():
      time.sleep(4)
      print("You drank coffee")
      def study():
      time.sleep(5)
      print("You finish studying")
      begin_time = time.perf_counter()
      x = threading.Thread(target=eat_breakfast, args=())
      x.start()
      y = threading.Thread(target=drink_coffee, args=())
      y.start()
      z = threading.Thread(target=study, args=())
      z.start()
      x.join()
      y.join()
      z.join()
      print(threading.active_count())
      print(threading.enumerate())
      print(time.perf_counter()-begin_time)