
Linux 3.4 kernel released - keyist
http://kernelnewbies.org/Linux_3.4
======
christianbryant
What I thought was more interesting (Linus noted "Nothing really exciting
happened since -rc7...") was the exchange between Linus and Peter Zijlstra, in
particular this Linus eruption:

<https://lkml.org/lkml/2012/5/19/97>

~~~
6ren

      > And I *do* know that the real world simply isn't simple enough that we could
      > ever do a perfect job, so don't even try - instead aim for "understandable,
      > maintainable, and gets the main issues roughly right".
    

It's striking that his manner is blunt and over-general... and his technical
content is also blunt and over-general. He's known for his pragmatic and
effective engineering decisions.

~~~
christianbryant
Found this article citing Peter on NUMA scheduling in March:

Toward better NUMA scheduling <http://lwn.net/Articles/486858/>

Peter's cited email: <http://lwn.net/Articles/486850/>

Actually, in reviewing the data, it seems this issue has been around for a
long time, and could be the root of Linus's irritation in the first place.
Perhaps he feels no headway is being made for such a long time, even the
smallest perceived misstep sets him off.

If nothing else, I would love to actually see some technically detailed papers
come out of this that get to the root of the problem, propose solutions to it,
and identify what of those solutions are being tested and when they are
expected to be implemented. Nothing like a good argument between engineers to
get a root cause rooted out and a solution in place.

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andrewvc
The X32 ABI is interesting. Who'd have thought this many years after 64 bit
becoming mainstream, (and decades after it becoming mainstream on servers)
something like this would be needed.

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slug
Anyone has a good argument why NOT to use this for every non memory intensive
application? I always thought that using 64bit pointers was a waste of memory
when not needed and this x32 abi to me seems fantastic since it keeps the
several advantages of newer 64bit cpus (more registers for example as
mentioned in the article).

~~~
seats
If an application is not memory intensive, why would you care if there is
'waste'? Personally I wish everyone would just move to 64 bit all the time.

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cpeterso
An application that uses 64-bit pointers but doesn't need 64-bits of _virtual_
address space is wasting _physical_ memory because your pointers are twice as
large. The application would waste physical memory pages and memory bus
traffic just to store 64-bit pointers with lots of unused zero bits like
0x00000000ffffffff.

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planckscnst
"...making slow start suboptimal" caught my eye, but I didn't understand the
rest. Is this for a specific circumstance or general? Did they find something
better than slow start or did they break it, causing it to be suboptimal?

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solox3
Is default support for dynamic graphics switching (~bumblebee) meant to be
implemented as part of the kernel or the graphics driver?

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mutex023
Has the slow USB copy bug been fixed yet?

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ibotty
there is progress on this. the bulk of this bug (these bugs) should have been
fixed one or three releases ago. there was a lwn article about it.

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nextparadigms
Wasn't this one supposed to have some Android kernel integration, too? Or
maybe the next one.

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hughw
Btrfs is getting the love.

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antimora
Is it me or Linux kernel releases becoming more frequent?

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zokier
It is you. Since 2005 (early days of 2.6), there has been four to five major
releases per year. 3.4 is the second release for this year, so it seems to
continue the trend almost perfectly.

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damncabbage
I'm confused. Is 3.x meant for a different class of system, or are distros
like Ubuntu intentionally lagging behind in 2.6.x land?

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pranjalv123
Ubuntu 12.04 runs kernel 3.2.

~~~
damncabbage
Ugh, thanks. I forgot I'm still running 11.10. I should've checked around
first.

