Linux Kernel Performance Bottlenecks Spotted By Mold Developer

[intelfx]

That means you make sacrifices elsewhere others may not be willing to make, including instruction code quality, size, potentially even sacrifice security considerations.

Can you back this up somehow, e.g. by quoting the maintainer saying that he's willing to make these sacrifices up to and including security, or by citing history of known issues in that regard?

Because if you can't, then this is called FUD.

[bug77]

Because the goal of MOLD is performance at all costs. That means you make sacrifices elsewhere others may not be willing to make, including instruction code quality, size, potentially even sacrifice security considerations.

I believe you're mistaking Mold (a linker) for a compiler.

[geerge]

To hear him tell it, you'd think so. He was more of a self-appointed spokesman for FOSS than a real leader, IMO. The FOSS movement he described was more how he wished to see it, than a faithful reporting of it as it really was.

Back in the day, someone published web comic featuring leading personalities from the FOSS movement and tech industry, called Everybody Loves Eric Raymond (which was itself a parody of the TV series Everybody Loves Raymond, which I should disclose that I've never seen).

https://geekz.co.uk/lovesraymond/

TL;DR: a grizzly, old libertarian blow-hard. Yes, he did actually write some code at one point in time.

Everybody Loves Raymond is alright if you like cheesy 90's sitcoms, mostly a vehicle for Ray Romano but the other regulars were decent. Nothing I'd go out of my way to watch, but if I owned a TV and it was on when it got turned on it might stay on until the ad break.

[Anux]

Depends on the SSD, FS, bus attachment, and how full it is. Broad generalizations like this aren't helpful in diagnosing problems of this sort. I found the details in the post lacking, as I'm sure some of the kernel devs will.

Dude, do you really think a dev today is using an SATA1 SSD? If so, the times should not be 1 or 2 seconds for the linking process but much more.
We can at least expect him to use an NVMe/PCIe2 SSD. And even if he was super greedy and bought the cheapest one he could get it still wouldn't be the cause for one second delay.

Edit: ah ok someone posted already ext4 and a Gen5 SSD.

[Guiorgy]

Dude, do you really think a dev today is using an SATA1 SSD?

I'm using Samsung PRO SATA... 😅

[ahrs]

Because the goal of MOLD is performance at all costs. That means you make sacrifices elsewhere others may not be willing to make, including instruction code quality, size, potentially even sacrifice security considerations.

There are also some instances where Mold fails to link correctly because of this lofty goal. I use Mold by default on my Gentoo system but occasionally I end up having to

env LDFLAGS="$(portageq envvar LDFLAGS | sed 's|mold|lld|g')" emerge …

or bfd, or gold, etc, if something has issues.

[coder]

Everybody Loves Raymond is alright if you like cheesy 90's sitcoms, mostly a vehicle for Ray Romano but the other regulars were decent. Nothing I'd go out of my way to watch, but if I owned a TV and it was on when it got turned on it might stay on until the ad break.

Thanks for filling in that detail.

As for Everybody Loves Eric Raymond, I don't recall it usually being super funny or insightful, but it's certainly possible I was missing some context. Interesting enough to look at, every now and then. No web comic I've seen holds a candle to XKCD.

[schmidtbag]

On an SSD this should take a few ms not a whole second.

Most of what I said is not limited to disk bandwidth. There's quite a lot of overhead to collect the necessary information and to communicate over the various busses.

[ssokolow]

I'm using Samsung PRO SATA... 😅

And, as far as I know, those things are SATA3, not SATA1, just like the cheap WD Blue SSDs in my mother's old laptop, my hand-me-down laptop, and the hand-me-down 2012 HP prebuilt that I turned into a "game console but not a console". Hell, the 2011 Athlon I used to be using does SATA3 and has a WD Blue I'll probably repurpose as I slowly part it out.

There's no reason aside from "test platform for preventing minimum requirements creep" for a developer to be using something that drives the link at 1.5Gbits instead of 6Gbits in this day and age.

[ssokolow]

No web comic I've seen holds a candle to XKCD.

Oglaf is pretty good.