Node.js Tutorial - 45 - I/O Queue

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I/O Queue

[fesbb]

Update: The inconsistency shown on 4:40 seems to be fixed on the latest versions of Node.js. The order is guaranteed being the timerCb() always executed before the readCb(), even when 1ms delay is passed.

[narotamkumarmishra]

Vishwas - you are one of the best educator of Youtube community (for Web Dev), just hats off to your technical knowledge and details, I am just fan of it, May God bless you and you keep creating such wonderful content.🙏

[thuanncats]

amazing video. I've been trying to follow the nodeJS official tutorial, but their event loop explanation was not the best. So your videos did save the day for me. Now I can confidently go back to that tutorial. Thanks again!

[matthewslyh]

Good info on the actual underlying setTimeout(..., 0) implementation. I never knew that. Also, using the huge for-loop at the end to "even the score" so to speak further reinforces the idea that these queues do not get run until the main thread is done or yields control. Nicely done! Great series!

[avijitsaha]

Now you are my coding hero. I watched so many channels for learning different topics. But I learned so much and all those things I learned I'll never forget those topics. Take love bro.

[awh]

I had read articles about these anamoly but never got exact reason. Thanks to u for that explanation 👌.

[googlemani]

Best Series on Nodejs, Enjoyed the explanation about different queues and it's priority of execution. Thank you.

[caaltz]

Dude is a real web mage, thanks Vishwas

[MultiMtech]

Hats off to you bro.. Nice explanation...

[loveutube]

Jahapana tussi great ho, toufa kubul karo

[mkrzyzowski]

in my tests readFile is always last. pehaps it depends on disk speed. any way setTimeout is always first in my tests.

[freebe]

Hello, Sir in further video you explain that fileread actually needs I/O polling to run in the first round and then a callback will be pushed into the I/O queue and in the second cycle won't the setTimeout CB function be present in the Timer queue.

[andreuamadeusayaipomacondo]

setimmediate is being called before I/O queue, when I try to run this kind of tests

[mohitpal]

Does the "emptied until live completion" only happens between promise queue and nextTick queue?

[prajwalm.s]

After completing a CB from I/O callback, will the event loop check the microtask queue again?

[ChineduUmeh-sp]

the inconsistency in the setTimeout() with I/O async with a 0 delay has been fix, so in my system it runs successfully

[mohitpal]

When it comes to Timer queue, does the callback function of setTimeout gets enqueued after the time passed has elapsed, or is it first enqueued and then the timer begins?

[shineLouisShine]

Mmm... this one, I'm sure I nailed.
First (no pun intended), conceptually, I find it ironic that a callback with a name such as "setTimeout" and with an argument of 0 - won't run first (before any other callback in the event loop beside the micro-tasks queue).
Second, the interval part is not entirly clear .
Why if the CPU was busy and the even loop start after 1:01 milisecond, there isn't inteval of max 1 milisecond as well.
And the reason that it is not clear is because THE TRIGGER of the inteval ITSELF isn't clear.

[Alexandru-OM]

Hello, I notice something strange. If I use node -v 16.x.x the above inconsistency is the same. But If I use node v 20.x.x it seems that the timer queue always comes before the I/O queue. Did not check the documentation but it seems that at some version between 16-20 this got changed

[krishdeva]

Bro please I need some suggestions from you
I'm currently Working as a python developer with 1.5 years of experience.
Two weeks before amazon contacted me and offered me a support engineer role
I got selected in the interview rounds.But I'm Confused whether to join or not
bcaz the mass layoffs
location: chennai amazon alexa data services
I'm a moderate in coding..Not an expert
Even if i go amazon and got layed off after 6 months..Can i get a good job after that? can this be affect my career and made a dent on my cv