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60x speed-up of Linux “perf”

eighty-twenty.org

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Re: 60x speed-up of Linux “perf”

#51

Post by vient »

vlovich123 wrote: post #14

I haven't blogged about this yet, but we saw a 1000x fold speed-up doing several things around symbolication. The more optimal approach we found was to use the gimli crate[1] directly & carefully optimize it to read in the data structures for the executable(s) you are symbolicating upfront & then issuing in-process queries. They also have a drop-in replacement of addr2line that outperforms it (both in symbolication s…

Looks interesting. I've encountered some annoying bugs with latest addr2line when trying to get symbols for addresses, wonder how gimli performs in that sense. Also, it seems that addr2line 2.37 has some performance regressions compared to 2.36.1 which I didn't look at yet.

Re: 60x speed-up of Linux “perf”

#52

Post by saagarjha »

faho wrote: post #20
varajelle wrote: post #15

Earlier quoted context omitted.

Is there not an exception in the license for "system libraries" which libbfd kind of is?

Is it? On my system the only things depending on binutils (which libbfd is part of) are gcc, clang and perf (seems archlinux doesn't care). That makes it arguably not a system library, so it's fair that Debian would want to steer clear of that interpretation.

What is Clang using it for? I thought it had its own suite of that.

Re: 60x speed-up of Linux “perf”

#53

Post by lnxg33k1 »

josephg wrote: post #42
lnxg33k1 wrote: post #36

Earlier quoted context omitted.

The thing is with GPL you have to contribute back, see how much Linux has grown in functionalities and how backwards are other kernels with MIT --- You may copy and distribute the Program (or a work based on it, under Section 2) in object code or executable form under the terms of Sections 1 and 2 above provided that you also do one of the following: a) Accompany it with the complete corresponding machine-readable so…

The most recent exploitation of opensource code comes from Amazon & friends making their own paid, hosted versions of redis, elastic search, mongodb, and so on. And not making any sort of proportionate contribution to the developers - whose free work their profits entirely rely on. And in this case I’m not sure how gpl helps. With gpl2 you only need to distribute source code if you distribute binaries - so they have…

Can someone with legalese knowledge make a license that states that you have to donate back 5% of the revenue you get from using a software?

Re: 60x speed-up of Linux “perf”

#54

Post by citrin_ru »

lnxg33k1 wrote: post #36
NelsonMinar wrote: post #31

Earlier quoted context omitted.

You understand there's nothing in the GPL that prevents companies from making billions on the code without compensating the contributors?

The thing is with GPL you have to contribute back, see how much Linux has grown in functionalities and how backwards are other kernels with MIT --- You may copy and distribute the Program (or a work based on it, under Section 2) in object code or executable form under the terms of Sections 1 and 2 above provided that you also do one of the following: a) Accompany it with the complete corresponding machine-readable so…

> The thing is with GPL you have to contribute back

Not contribute, but share the sources if they distribute a binary which uses code derived from GPL-ed one. Wireless router vendors used to share modified sources as an archive on some obscure ftp without comments and documentation (so you'll have a hard time building a binary from these sources). It's better than nothing, but this is not a contribution.

Re: 60x speed-up of Linux “perf”

#55

Post by fabianhjr »

josephg wrote: post #42
lnxg33k1 wrote: post #36

Earlier quoted context omitted.

The thing is with GPL you have to contribute back, see how much Linux has grown in functionalities and how backwards are other kernels with MIT --- You may copy and distribute the Program (or a work based on it, under Section 2) in object code or executable form under the terms of Sections 1 and 2 above provided that you also do one of the following: a) Accompany it with the complete corresponding machine-readable so…

The most recent exploitation of opensource code comes from Amazon & friends making their own paid, hosted versions of redis, elastic search, mongodb, and so on. And not making any sort of proportionate contribution to the developers - whose free work their profits entirely rely on. And in this case I’m not sure how gpl helps. With gpl2 you only need to distribute source code if you distribute binaries - so they have…

AGPL-like clauses classifying usage through network as distribution would help there and many platform capitalism[1] companies are against AGPL[2] for that reason.

[1]: https://theceme.org/richard-godden-platform-capitalism-nick-...

[2]: https://opensource.google/docs/using/agpl-policy/

Re: 60x speed-up of Linux “perf”

#56

Post by faho »

saagarjha wrote: post #52
faho wrote: post #20

Earlier quoted context omitted.

Is it? On my system the only things depending on binutils (which libbfd is part of) are gcc, clang and perf (seems archlinux doesn't care). That makes it arguably not a system library, so it's fair that Debian would want to steer clear of that interpretation.

What is Clang using it for? I thought it had its own suite of that.

This... is some weirdness in Arch's clang package.

It depends on gcc, for some reason, and that depends on binutils?

(and I have no idea if anything here uses libbfd, since it's just a part of the binutils package and not split out)

Re: 60x speed-up of Linux “perf”

#57

Post by [deleted] »

faho wrote: post #3

> Michał Sidor suggests building against libbfd, something that the Debian maintainers don’t want to do. "don't want to" isn't quite correct - they can't . Perf is licensed under the GPLv2, libbfd under the GPLv3. The licenses are incompatible, which makes the combination unredistributable - which is what Debian would be doing with it. Debian is legally not allowed to do this.

[deleted]

Re: 60x speed-up of Linux “perf”

#58

Post by pathseeker »

lnxg33k1 wrote: post #22
junon wrote: post #2

Yet another case of GPL virality causing more issues than it solves. E: Downvoters, have you read the article? The program started a new process for each address lookup instead of using a library because that library is GPL. Shall we have a discussion?

I guess MIT and Apache would be better, so that company can make billions on the code and contributors would still be poor (see AAPL -> FreeBSD)

Right, and GPL is making all of us open source devs rich. I can't fathom getting into open source and then getting mad when people use your tools to great success.

Re: 60x speed-up of Linux “perf”

#59

Post by yakubin »

globular-toast wrote: post #23
yakubin wrote: post #7

Earlier quoted context omitted.

The "or later" clause is a backdoor. Not wanting backdoors in your license doesn't seem like a bad reason to me.

So what's the solution? You can use a permissive licence which has a huge "backdoor" allowing derivatives to turn up under any licence, including GPLv3 (or v4). Or you can use GPLv2 with no "or later" clause which means you get situations like this.

This incompatibility is a unique feature of GPL. Wherever it goes, it's incompatible with something (in this case, with itself). You could use MPL or CDDL and, as long as GPL isn't involved, you won't have problems with license compatibility.

However, in the case of the Linux kernel (which "perf" is distributed with) changing the license is not an option --- no CLA and, even if it was practical to ask so many people for permission, many contributors are dead now. So here the only option is using dependencies which are compatible with GPLv2. So maybe we need a new library to replace libbfd, which would be more permissively licensed.

Re: 60x speed-up of Linux “perf”

#60

Post by jraph »

AstralStorm wrote: post #6
junon wrote: post #2

Yet another case of GPL virality causing more issues than it solves. E: Downvoters, have you read the article? The program started a new process for each address lookup instead of using a library because that library is GPL. Shall we have a discussion?

No. That is the case of Linus Torvalds not using the standard "or later" clause. He has his (bad) reasons. The incompatibility is caused by "lack of restrictions" clause. Without that, GPL becomes essentially BSD with all the corporate thievery that entails.

Well, I don't think I agree with him and would licence GPL code with the "or later" clause, but he has a very reasonable and convincing argument against it.

See this video of him explaining his take on GPLv3 and the "or later" clause at Deb Conf if you are interested: https://www.youtube.com/watch?v=PaKIZ7gJlRU

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