Some Of The Workloads Still Seeing Lower Performance On Linux 5.5 Git

[caligula]

No gain/use in return? You constantly say how easy it is to find regressions using the PTS, yet whenever you uncover one you make it sound like a big deal to actually submit a bug report to get it fixed

I realise writing articles makes you money, but reporting bugs - especially ones that are affecting yourself - pays off when they're fixed!

The most infuriating thing is bisecting is the time consuming hard part, submitting what you've found is the _easy_ part, it makes sure that the right people are notified and can start working on a fix or revert

Typical open source mentality. He's already done the most significant contribution here. Maybe the incompetent coders who introduced the regression should pay more attention to the largest Linux news sites when the articles are discussing their work? How is it possible that they're not interested?

[Guest]

The kind of code copyright license doesn't impact software bugs here.

FTFY. You're right in essence though, it's the software development methods used that matter, and the efforts taken by the software developers.

[Guest]

If the PTS is capable of bisecting these issues using graphs and what not, why not get it to submit the bug report automatically directly to bugzilla

I know the Gentoo tinderbox used to submit bug reports to the Gentoo bugzilla so I know this automation is possible

Because it would start flooding kernel bugzilla with automated bots and no replies to queries from kernel developers. Especially if mitigations were added for hardware vulnerabilities like Spectre and Meltdown.

[FireBurn]

FireBurn @others he has to make a living. plus he's not really affected by the bug. he has material to write about regardless of kernel status. i say he's doing a great job already. you have seen the bug already so why don't you do your own test and file a bug report? he's only one person. maybe more can do the test and see for themselves how that appblabla (i'm lazy to look for the name) change the performance. the phoronix test suit it out there. just give it a try and then you can report the issue.

I do report all the bugs I find, I _do_ spend the time manually bisecting the kernel and mesa when I find an issue. I didn't notice this one because I don't use apparmour

The point is I _do_ give back and do help to get things fixed, Michael on the other hand seems to care about producing another article more than actually fixing the issues he's finding

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/log/?qt=grep&q=mike%40fireburn.co.uk

https://cgit.freedesktop.org/mesa/mesa/log/?qt=grep&q=mike%40fireburn.co.uk

There are others sprinkles around other projects too

[FireBurn]

Because it would start flooding kernel bugzilla with automated bots and no replies to queries from kernel developers. Especially if mitigations were added for hardware vulnerabilities like Spectre and Meltdown.

I'm not saying it should submit it automatically, but if you are hunting for a bug it would be great to be able to submit it from the PTS once you've found it

[mbello]

From past experience, this article will quickly reach the relevant kernel dev.

[FireBurn]

From past experience, this article will quickly reach the relevant kernel dev.

And how much time has that wasted?

[ferry]

The point is I _do_ give back and do help to get things fixed, Michael on the other hand seems to care about producing another article more than actually fixing the issues he's finding

Open source is done by a mixture of volunteers and paid professionals. And even volunteers have their own reasons to contribute. So regardless your reasons thanks for contributing!

But let's not forget Micheal is a paid professional, his business is writing stories that people want to read. We read it, so it worked. Fixing or reporting the issue or not is not his job and would be entirely voluntary.

[kozman]

Hey all. I took the time to write an email to John Johansen and this is what he replied:

"I don't read Phoronix unless some one points me at a specific article. That particular issue was identified and the patch already exists. It didn't get pushed yet as another issue was raised that I was hoping to send in at the same time. I will be sending a pull request out today."

So looks like they know about it and are fixing it.

[kozman]

The fix for this has been posted for RC5:
The following changes since commit fd6988496e79a6a4bdb514a4655d2920209eb85d:

Linux 5.5-rc4 (2019-12-29 15:29:16 -0800) are available in the Git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor tags/apparmor-pr-2020-01-04

for you to fetch changes up to 8c62ed27a12c00e3db1c9f04bc0f272bdbb06734:

apparmor: fix aa_xattrs_match() may sleep while holding a RCU lock (2020-01-04 15:56:44 -0800) ----------------------------------------------------------------
+ Bug fixes - performance regression: only get a label reference if the fast path check fails
- fix aa_xattrs_match() may sleep while holding a RCU lock
- fix bind mounts aborting with -ENOMEM
----------------------------------------------------------------
John Johansen (2):
apparmor: only get a label reference if the fast path check fails
apparmor: fix aa_xattrs_match() may sleep while holding a RCU lock

Patrick Steinhardt (1):
apparmor: fix bind mounts aborting with -ENOMEM