Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Show HN: A “living” Linux process with no memory

github.com

Post reply on HN
Print view View original

51–60 of 117 posts

Re: Show HN: A “living” Linux process with no memory

#51

Post by ebg13 »

Dylan16807 wrote: post #31
kick wrote: post #10

Earlier quoted context omitted.

There's also a strong argument to be made that people shouldn't have to care about ecosystems that are so delicate that a proof of concept in a previous version "hurts the overall [ecosystem]." "How dare you use a hammer! We're all using Hammer 2 now! I don't care that it was 'Only one nail," put it down and pick up Hammer 2! Your hammer is what, ten years old? That's ancient! It's not even compatible with my Hammer…

To make the analogy work I have to imagine that the two hammers cause horrible problems when used at the same time, and that they're both free with 5 minute shipping. It's a sucky situation to be in, but we should probably get everyone on the same hammer. (If we want a somewhat less nonsensical analogy, replace hammer with screwdriver. Two incompatible screw head patterns and you can only use one driver on any partic…

> But all of this is a dumb tangent, and we should just appreciate how funny it is to ask that this nonsensical pointless quasi-OS-breaking code be done in python 3 instead.

I'll admit that I did not expect it to start a thread.

Re: Show HN: A “living” Linux process with no memory

#52

Post by kick »

Dylan16807 wrote: post #44
kick wrote: post #42

Earlier quoted context omitted.

Wouldn't occur in this case, as the script starts with: #!/usr/bin/env python2

You're arguing against something I never said. Yes, this file, completely in isolation, has no problem. But people want to different pieces of python code together. If one or the other only works with a specific version, it becomes a problem when you try to combine them. Therefore, best practice is to get everyone on the same version. We want to stop having to ask which version everything is, and facing the disappoin…

...use the hammer that didn't arbitrarily break compatibility, then? (Note that the original analogy pointed out that they couldn't be mixed, anyway: "or even take advantage of the nails you've hit!")

This is like complaining that the well is poisoned when you're the one who put arsenic in it.

This also isn't even an open source project, so it's not like you can mix and match anyway.

Re: Show HN: A “living” Linux process with no memory

#53

Post by gue5t »

geofft wrote: post #11

I've now seen a similar case multiple times in the wild - if a process has a thread in uninterruptible sleep (e.g., blocked on a bad disk or a stuck network filesystem) and you kill it, the process dies, but the kernel waits forever for that thread before informing the parent process. The parent doesn't get SIGCHLD, and wait() doesn't return. (So, for example, your favorite init/supervisor won't restart the process o…

The solution to this situation, as I understand it (on Linux), is TASK_KILLABLE, which effectively supercedes uninterruptible sleep as a concept: https://lwn.net/Articles/288056/

But TASK_KILLABLE is not used in most places it should be. Patching your (least) favorite driver to use TASK_KILLABLE could be a good entry point to contributing to the kernel.

This older, tangential HN discussion and the comments on LWN have a bit more info: https://news.ycombinator.com/item?id=18056946

Re: Show HN: A “living” Linux process with no memory

#54

Post by jldugger »

croo wrote: post #9

> Why? I don't know. I thought it was funny This is the profit. While job searching I went on an interview where I got asked why I did a side gig listed on my resumee. "For friend or for money?" It was neither and I said "I don't know, because programming is fun?" I got hired.

> I got hired.

So, for money.

Re: Show HN: A “living” Linux process with no memory

#55

Post by darkwater »

klyrs wrote: post #22
rat9988 wrote: post #5

Earlier quoted context omitted.

He could. You also could have done it in Python3, and you still can.

"He" is named Isabella. https://github.com/izabera

Why pointing this detail out is being downvoted? It is a polite message and it is correct above all. Don't upvote it if you think it's not that relevant (I personally think it is) but don't downvote it either.

Re: Show HN: A “living” Linux process with no memory

#56

Post by jshevek »

jldugger wrote: post #54
croo wrote: post #9

> Why? I don't know. I thought it was funny This is the profit. While job searching I went on an interview where I got asked why I did a side gig listed on my resumee. "For friend or for money?" It was neither and I said "I don't know, because programming is fun?" I got hired.

> I got hired. So, for money.

Not all of the outcomes of our actions give evidence for the motivations for our actions.

Re: Show HN: A “living” Linux process with no memory

#57

Post by OJFord »

darkwater wrote: post #55
klyrs wrote: post #22

Earlier quoted context omitted.

"He" is named Isabella. https://github.com/izabera

Why pointing this detail out is being downvoted? It is a polite message and it is correct above all. Don't upvote it if you think it's not that relevant (I personally think it is) but don't downvote it either.

Maybe it's a level deeper, the down-voters objecting to the assumption that 'he' can't be called 'Isabella'!

(I haven't voted either way and have no strong feelings on it, just pointing out how doomed this line of objection/correction is. Personally I generally say 'they' or 'the OP', and did long before (all my life) I was aware of anyone having pronoun preferences, it's just correct isn't it? Never used to be a problem. 'Is that a person over there?' 'Yes, they're just in a funny pose.')

Re: Show HN: A “living” Linux process with no memory

#58

Post by Dylan16807 »

kick wrote: post #52
Dylan16807 wrote: post #44

Earlier quoted context omitted.

You're arguing against something I never said. Yes, this file, completely in isolation, has no problem. But people want to different pieces of python code together. If one or the other only works with a specific version, it becomes a problem when you try to combine them. Therefore, best practice is to get everyone on the same version. We want to stop having to ask which version everything is, and facing the disappoin…

...use the hammer that didn't arbitrarily break compatibility, then? (Note that the original analogy pointed out that they couldn't be mixed, anyway: "or even take advantage of the nails you've hit!") This is like complaining that the well is poisoned when you're the one who put arsenic in it. This also isn't even an open source project, so it's not like you can mix and match anyway.

I didn't make python 3, and "stick on python 2 forever" doesn't seem like the solution here as far as I can tell.

> This also isn't even an open source project, so it's not like you can mix and match anyway.

Again focusing on the execution of one specific project, as-is, is beside the point of "get everyone on the same hammer".

Re: Show HN: A “living” Linux process with no memory

#59

Post by state_less »

kd22 wrote: post #43
saagarjha wrote: post #41

Earlier quoted context omitted.

Can someone write a program to tell me how much money I’d need to give you?

Give me time and I'll tell you at the end how much money you need to give me.

No need to be difficult, just give me an estimate. Is this going to be a small, medium or large t-shirt size task?

Re: Show HN: A “living” Linux process with no memory

#60

Post by amelius »

geofft wrote: post #11

I've now seen a similar case multiple times in the wild - if a process has a thread in uninterruptible sleep (e.g., blocked on a bad disk or a stuck network filesystem) and you kill it, the process dies, but the kernel waits forever for that thread before informing the parent process. The parent doesn't get SIGCHLD, and wait() doesn't return. (So, for example, your favorite init/supervisor won't restart the process o…

For anyone who was wondering, I found a post explaining why threads can be in "uninterruptible sleep" in the first place:

https://eklitzke.org/uninterruptible-sleep

Post reply on HN