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Threadripper 3960X Compiles Linux Kernel in Under 30 Seconds

phoronix.com

21–30 of 57 posts

Re: Threadripper 3960X Compiles Linux Kernel in Under 30 Seconds

#21
post #19

I don't really understand why this is newsworthy, so maybe someone could help me understand. It's a big, power hungry desktop CPU with incremental performance gains over the last generation. Why is this important? Is there some kind of architectural breakthrough these CPUs are using? Are these CPUs recovering performance lost to Spectre/Meltdown mitigation?

3970x almost halves the LLVM compilation time compared to 2990wx using the same core count. I would call that more than incremental performance gain.

Why? Isn't that within a modest error margin for the general arc of these? I'm looking at this graph over time and it seems like a linear projection wouldn't be broken by this.

"The next generation of processors is not quite twice as fast as the current generation" just seems like a pretty normal statement to me.

Re: Threadripper 3960X Compiles Linux Kernel in Under 30 Seconds

#22
post #12

I was compiling the kernel for my boxes for the most part of the 90's and 00's and the funny thing is a sub-60-second compile time was always possible with the "latest gear". Like a 100 MHz pentium. Of course the number of modules you want/need to compile has steadily increased but still funny to see someone impressed with a 30 second compile time 25 years later and with a 100x+ increase in CPU power :)

The kernel has gotten bloated. Back in the day, it could easily run in 8 megabytes of RAM, with plenty left over for the userspace and cache. Nowadays, just the kernel code (before loading any modules) is already bigger than that.

Re: Threadripper 3960X Compiles Linux Kernel in Under 30 Seconds

#23
post #16
post #12

I was compiling the kernel for my boxes for the most part of the 90's and 00's and the funny thing is a sub-60-second compile time was always possible with the "latest gear". Like a 100 MHz pentium. Of course the number of modules you want/need to compile has steadily increased but still funny to see someone impressed with a 30 second compile time 25 years later and with a 100x+ increase in CPU power :)

Everybody knows the REAL test is a FreeBSD 'make world' anyway :)

I used to think 'make world' on BSD was some big deal until I started to synthesize HDL code to bitfiles or GDS.

Re: Threadripper 3960X Compiles Linux Kernel in Under 30 Seconds

#25

Earlier quoted context omitted.

That's why I also use the LLVM compilation test (C++) and other workloads besides just the Linux kernel... But it seems the Linux kernel results are always what generates the most interest.

I would bet it's just familiarity. Most people that are interested in PCs have heard of Linux, and know that it has a Kernel. Or they even have already compiled kernels themselves. Whereas LLVM is more of a thing that is known to a subset of software developers. I'm personally happy to see the LLVM tests, since it gives a good impression on what benefits software developer which work on big native code-bases can expe…

I think it's path dependence. The kernel has a large number of compile-time configuration options; back in the 90s, it was common to compile your own kernel, after tuning these options to your own particular hardware. It was also common to get new kernel releases (as a source code .tar.gz, or as a patch to the previous source code .tar.gz) directly from kernel.org, instead of waiting for the next release of the distribution you were using. So the time it took to compile a new version of the kernel for your machine was something many Linux users had experience with, and it was clear when a machine was faster (perhaps as a consequence of having previously compiled and installed a newer kernel!) because it took less time to compile the kernel. To turn that into a benchmark was just a matter of standardizing on a kernel release and a set of configuration options.

Re: Threadripper 3960X Compiles Linux Kernel in Under 30 Seconds

#26
post #19

Earlier quoted context omitted.

3970x almost halves the LLVM compilation time compared to 2990wx using the same core count. I would call that more than incremental performance gain.

Why? Isn't that within a modest error margin for the general arc of these? I'm looking at this graph over time and it seems like a linear projection wouldn't be broken by this. "The next generation of processors is not quite twice as fast as the current generation" just seems like a pretty normal statement to me.

The last decade has been pretty stagnant in CPU development. That AMD has gotten ahead, and is making significant CPU advancements in each generation for the past two years, is something we haven't seen in 10-15 years.

Re: Threadripper 3960X Compiles Linux Kernel in Under 30 Seconds

#27
post #19

Earlier quoted context omitted.

3970x almost halves the LLVM compilation time compared to 2990wx using the same core count. I would call that more than incremental performance gain.

Why? Isn't that within a modest error margin for the general arc of these? I'm looking at this graph over time and it seems like a linear projection wouldn't be broken by this. "The next generation of processors is not quite twice as fast as the current generation" just seems like a pretty normal statement to me.

Dont take these gains for granted. We're nearing the physical limit for current technologies. Transistors a handful of atoms across. My guess is in 20 years we will celebrate a 5 percent gain.

Re: Threadripper 3960X Compiles Linux Kernel in Under 30 Seconds

#28
Wow... I still remember recompiling the NetBSD kernel on my Amiga 3000 to tweak the timings on my Retina Z3. Took 14 hours to compile the kernel...

So if processors are now >1500x faster than they were in 1991, why is it that my Amiga 3000 has a faster, more responsive UI?

Why is it that an ssh session takes 8 seconds to establish?

Why is it that browsing a network share is 10x slower than viewing a file list was on a BBS?

Re: Threadripper 3960X Compiles Linux Kernel in Under 30 Seconds

#29

Wow... I still remember recompiling the NetBSD kernel on my Amiga 3000 to tweak the timings on my Retina Z3. Took 14 hours to compile the kernel... So if processors are now >1500x faster than they were in 1991, why is it that my Amiga 3000 has a faster, more responsive UI? Why is it that an ssh session takes 8 seconds to establish? Why is it that browsing a network share is 10x slower than viewing a file list was on…

Because not everything is CPU bound.

Re: Threadripper 3960X Compiles Linux Kernel in Under 30 Seconds

#30

Wow... I still remember recompiling the NetBSD kernel on my Amiga 3000 to tweak the timings on my Retina Z3. Took 14 hours to compile the kernel... So if processors are now >1500x faster than they were in 1991, why is it that my Amiga 3000 has a faster, more responsive UI? Why is it that an ssh session takes 8 seconds to establish? Why is it that browsing a network share is 10x slower than viewing a file list was on…

Something's wrong with your DNS setup, I guess. SSH session takes less than one second to establish for me.
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