[laumars]

I’m not related to the GP.

Let me explain the point further:

Your readme has a performance section, that section focuses on nnn vs two other tools. You only benchmark against Memory usage under normal circumstances (ie no other performance metric, no other file system nor device types, etc). Then you have a whole other page dedicated to “why is nnn so much smaller” which is directly linked to from the performance comparisons. There’s no other way to take that other than you’re directly comparing nnn to other tools and objectively saying it’s better.

So with that in mind, I think the developers of the other tooare totally with in their right to challenge you on your claims.

Edit: the “multiple contributors” point you made is also rather dishonest too. It’s your personal GitHub account for a project you chiefly contribute too and the documents in question were created and edited by yourself (according to git blame). Yes nnn has other contributors too but it was yourself who wrote and published the claims being questioned.

[apjana]

> totally with in their right to challenge you on your claims

Yes, and within the limits of common courtesy.

The other utility does only one thing - reports disk usage so there's not much to compare. The dev did mention that `ncdu's memory usage is definitely its weak point`.

> no other performance metric, no other file system nor device types

because lstat64() is at the core of the performance metric of the feature we are comparing here and with the same number of files on the same storage device the number of accesses are exactly the same. The only metric that differentiates the utilities is memory usage.

> Edit: the “multiple contributors” point you made is also rather dishonest too.

Not really, I prefer to edit the readme myself because I want to keep the documentation clean. You will see features contributed by other devs for which I have written the docs from readme to manpage. Regarding the metrics, sometimes I have taken the data and sometimes I have requested someone else to collect it. Or doesn't that count as contribution?

[laumars]

What I actually care most about a file manager is how they perform on mounts with low IOPS and how gracefully they handle time outs and other exceptions.

RAM is cheap and any file manager will be snappy on an SSD. But edge cases are where most file managers fall apart yet are situations where you might need to depend on your tools the most.

However now I understand the point of this project was purely to optimise against memory usage, I can better understand the arguments you were making.

> or doesn't that count as contribution?

Not in this case, no. You published it, so you’re still ultimately accountable for it.

You cannot request figures then play the “nothing to do with me guv’” card when someone queries the benchmarks that you subsequently published. At best it comes across as an unlikely story; at worst you’re still complicit.

[imtringued]

>RAM is cheap

This is the wrong mindset. RAM is only cheap if you don't use it. As soon as you go just 1 byte over the maximum RAM it turns into the most precious resource of the entire computer.

If an app uses more memory than another then it is not better because RAM is cheap. It is better because it provides more or higher quality features at a reasonable cost of increased memory usage. But at the same time it is also worse for people who do not need those features.

Here is an example: When I launch the graphical file manager nautlius it consumes roughly 26 MB of RAM showing my home folder but when I go to my "Pictures" folder it suddenly shoots up to 300MB. There is a reason for that and it is not "RAM is cheap", if that were the case it would always use 300MB regardless of what I do with it (electron apps are a major offender of this). Nautlis consumes that much RAM because it has more features like displaying 1000 thumbnails of all those pictures.

Now this feature would get in my way if I set up something like a Raspberry Pi Zero to take a photo every hour. Nautilus will crash because it needs too much memory to display the thumbnails.

[laumars]

I agree from an idealistic point of view (I've often make the same argument myself with regards to non-native applications and self-indulgent GUIs) but you're missing the context of the argument here.

We're not talking about burning through hundreds of megabytes (nor even gigs) on a pretty UI that adds no extra function; we are talking about only a few megabytes to save stressing low bandwidth endpoints.

It isn't 1990 any more, sacrificing a few megabytes of RAM in favour of greater stability is very much a worthwhile gain in my opinion. Hence why I say RAM is cheap - we don't need to cut every corner just to save a few bytes here and there.

In the example we were discussing, the idle RAM usage was higher because it doesn't hammer low bandwidth endpoints with frequent rescans. Caching is actually a pretty usage for spare RAM - your kernel does it too. So we are not talking about anything out of the ordinary here and we're certainly not talking about wasting RAM for the sake of wasting RAM. We're talking about trading some cheap RAM for the sake of potentially expensive (computationally speaking) access times.

However I do feel I need to reiterate a point I've said throughout this discussion: there is no right or wrong way; it's just a matter of compromise. eg the goals for an embedded system would be different to the goals for an CLI tool on a developers laptop.

[apjana]

> then play the “nothing to do with me guv’” card when someone queries the benchmarks that you subsequently published

No, you are cooking things up. I did respond as per my understanding. My statement was very clear - "_Please don't judge me_ by the project page of a utility which is a work of several contributors."

I had problems with the _personal remarks_. And I am not surprised you chose to ignore that and describe it in the light that I have problem with someone challenging the benchmarks.

I am yet to come across figures that can challenge the current one.

[smashedtoatoms]

I have no idea how people convince themselves to contribute to open source and/or participate regularly in online discourse. It’s basically working really hard for the easiest-to-offend and least-likely-to-appreciate-anything-you-do people on earth, so they can throw shade at everything you do, and then get mad because you did something different than they would have done.

FWIW, I appreciate everything you all are doing, even the stuff I’m not using right now. You all don’t hear it enough, and you’re certainly not getting paid enough for what you’re doing.

[laumars]

I contribute loads to open source too.

It’s actually not that hard to do so without talking trash about other projects. In fact I find those kind of comparisons are often the laziest and least researched ways of promoting a particular project as anyone who’s spent any time dissecting other peoples work in detail (not just running ‘ps’ in another TTY) will usually gain an appreciation for the hard work and design decisions that have gone into competing solutions.

But that’s just the opinion of one guy who has been contributing to the open source community for the last two decades. ;)

[apjana]

> talking trash about other projects

Cleverly fabricated and blown out of proportions. Yes, 2 decades of rich experience sure teaches that!

To clear the context for others, you are talking about a list of performance numbers here, and as I said, I am yet to come across figures that can challenge the current one.

[apjana]

> What I actually care most about a file manager is how they perform on mounts with low IOPS

Purely technical questions (let's put `being very snarky` and `dishonesty` and my other irrelevant personal traits aside):

- How does "low IOPS" affect readdir()/scandir() and lstat64() in two C utilities differently?

- What else would be affected?

[laumars]

It’s about how and when they get used. Eg if you’re running on a lower performing mount then you might want to rely on caches more than frequent rescans. What I would often do on performance critical routines running against network mounts was store a tree of inodes and time stamps and only rescan a directory if the parents time stamp changed. It meant I’d miss any subsequent metadata changes to individual files (mtime, size, etc) but I would capture any new files being created. Which is the main thing I cared about so that was the trade off I was willing to make.

There’s no right or wrong answer here though. Just different designs for different problems. Which was also the point the other developer was making when he was talking about his memory usage.

[apjana]

> There’s no right or wrong answer here though.

The processor cache plays an important role which you are ignoring.

External storage devices: most of the time they are write-back and even equipped with read-ahead. Yes, I know there are some exceptions but if you are write-through non-read-ahead you _chose_ to be slow in your feedback already and this discussion doesn't even apply.

Network mounts: cache coherency rules apply to CIFS as well. And again, if you _choose_ to ignore/disable, you are OK to be slow and this discussion does not apply.

If `nnn` take n secs the first time, another utility will take around the same time on the first startup (from a cold boot).

Now the next scans where you go into subdirs would be much faster even in `nnn` due to locality of caching of the information about the files (try it out). The CPU cache already does an excellent job here. And if you go up, both `nnn` and the other utility would rescan.

> point the other developer was making

Yes, he was saying - my memory usage may be 15 times higher because of storing all filenames (in a static snapshot!!!) but you are dishonest if you show the numbers from `top` output without reading my code first for an education of my utility.

[laumars]

I’m not sure what you mean by processor cache here. The processor wouldn’t cache file system meta data. Kernels will, but that is largely dependant on the respective file system driver (eg none of the hobby projects I’ve written in FUSE had any caching).

Different write modes on external hardware also confuses the issue because you still have the slower bus speeds (eg a USB2 for an older memory stick) to and from the external device than you might have with dedicated internal hardware.