understanding mmap, the workhorse behind keeping memory access efficient in linux

Поділитися
Вставка
  • Опубліковано 19 жов 2024

КОМЕНТАРІ • 30

  • @yonahcitron226
    @yonahcitron226 Рік тому +11

    It’s a joke that this is available online for free. Absolute gold. Love every minute!

  • @j5ylim396
    @j5ylim396 Рік тому +7

    wished my lecturers were like this. great one man, cheers

  • @whata4head666
    @whata4head666 4 роки тому +9

    Greetings from Brazil Chris, just wanna say thank you, you're really helping me :)

    • @ZubairAhmad-wu2tw
      @ZubairAhmad-wu2tw 3 роки тому

      you might also want to watch "Tech Instance" ua-cam.com/users/TechInstance

  • @kafoby8732
    @kafoby8732 3 місяці тому

    Thank you for making these lectures FREE!!

  • @flyxtop
    @flyxtop 4 роки тому +4

    thanks I learned some things today again! (I knew this earlier but it's interesting every program or library exists as a file)

    • @ZubairAhmad-wu2tw
      @ZubairAhmad-wu2tw 3 роки тому

      give "Tech Instance" a try too ua-cam.com/users/TechInstance

  • @stevewu9372
    @stevewu9372 3 роки тому +3

    Thank you, Chris, I learned a lot from you!

  • @DJ-vx9gl
    @DJ-vx9gl 2 роки тому +3

    Wonderful explanations, thank you!

  • @ninjazhu
    @ninjazhu Рік тому +1

    That is one method of implementing VM. There are multiple methods. Not all hardware has the came features which limits sometimes which techniques are used and can even force you to think outside the box which programmers should do anyway.

  • @urbankoistinen5688
    @urbankoistinen5688 3 місяці тому

    It is also worthwhile to test that the system does what the documentation seems to imply it should do.
    Try mmap on a large file using different flags, see what happens when the file is cashed in main memory.

  • @glenyeldho5782
    @glenyeldho5782 4 роки тому +3

    Waiting for the next video in this series 😁😁

    • @ZubairAhmad-wu2tw
      @ZubairAhmad-wu2tw 3 роки тому

      I found Y/T channel "Tech Instance" helpful too ua-cam.com/users/TechInstance

  • @wonderfulworld2475
    @wonderfulworld2475 6 місяців тому +1

    When someone on UA-cam compress your 4 hour lecture into 20mns :D

  • @demablogia
    @demablogia 2 роки тому +4

    Great video, thanks. One question: when source is compiled & linked into an ELF file , this file doesn't have any virtual address but local offsets. So , I guess, someone and sometime translate those local offsets to virtual adresses . Is the code (.text, .data ) stored into real memory modified ( by someone ) with virtual address references ? Or code stored into real memory still has got offsets ?

    • @Henry-sv3wv
      @Henry-sv3wv Рік тому +3

      (i am no expert, just writing what i just learned from web)
      * every process only "sees" virtual memory.
      * a static linked ELF contains no symbols and is ready to run with a fixed entry point address.
      * an ELF that uses dynamic libraries contains symbols and needs dynamic linking which is done by the loader ( ld-linux )
      In my current Arch Linux the dynamic linker/loader ld-linux is: ld-linux-x86-64.so.2 coming from the glibc 2.36 library package. (it itself is a statically linked ELF executable)

  • @janshaka
    @janshaka 4 місяці тому

    Thank you!

  • @nang88
    @nang88 3 роки тому +1

    cool

  • @gleventhal
    @gleventhal 8 місяців тому +4

    Boy, do I love when a native english speaker who actually knows the topic well presents a technical topic this well. Thanks for being you!

  • @alex_d_lee
    @alex_d_lee 5 місяців тому

    this is so good

  • @venumaj112
    @venumaj112 4 роки тому +3

    Is it possible to use mmap which is huge pages backed ?

    • @gleventhal
      @gleventhal 8 місяців тому

      Yes, see the man page (MAP_HUGETLB and MAP_HUGE_2MB, etc)

  • @jiezhang5325
    @jiezhang5325 3 роки тому +1

    This vedio solve my confusion!

  • @winstonacousticstudio445
    @winstonacousticstudio445 4 роки тому

    how many weeks does this course last for?

    • @ChrisKanich
      @ChrisKanich  4 роки тому +3

      It's a 15 week course - I put a link to the schedule in the description.

  • @halleluyahwoldesenbetbrhan1099

    where can i get the slides

  • @arunraju9705
    @arunraju9705 2 роки тому +2

    0.75 speed is good.