how do you guys handle qtwebengine

[logrusx]

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2024-10-14T12:47:02 >>> dev-qt/qtwebengine: 9:19:17

on

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Intel(R) Core(TM) i5-7600T (4) @ 3.70 GHz

with 32GiB of RAM.

Holy compilation marathon, Batman!
I knew qtwebengine was big, but that big? Although I had USE=-jumbo-build.
Has anyone measured how much jumbo-build reduces the compilation time? In percents?

It's been a while since I actually tried, but I would still guess it should be about 50% of the time with 'jumbo-build' disabled (assuming the increased memory-use will not be a problem).

Back in the days of jumboo-enabled chromium builds it was something like 7 hours compared to more than 35 hours for my poor old E6200 - dual core dual thread processor with 6 GB of RAM.

Also I always thought it was based on webkit and not the chromium (blink) fork.

There was Qt Webkit [1], which kind of fell into slumber, and eventually lost its outside-Qt maintainers as well.

1. https://code.qt.io/cgit/qt/qtwebkit.git/

Chromium was initially based on webkit but that was more than a decade ago. That's why it was fast and compiled quickly. Then I abandoned Linux for a while and I don't know when it dropped the webkit part and became the monster that it now is.

Webkit itself was an internal Apple project that I think Safari was based on. It may still be.

p.s. I just checked because I remember something about KDE. Webkit is a fork of KHTML.

Best Regards,
Georgi

[Zucca]

Counterpoint: -O0 disables optimizations that lead to smaller code size, which means that the linker needs to do more work to link it all.

Ah. I didn't think that... Good (counter)point. ;)

Anyways... webkit-gtk seems quite lighter to compile:

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2024-10-15T03:44:16 >>> net-libs/webkit-gtk: 5:38:39

.
I might as well now rebuild both with USE=jumbo-build... Let's gather some statistics.

[Zucca]

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M710q ~ # qlop
2024-10-15T22:49:10 >>> net-libs/webkit-gtk: 1:51:00
2024-10-16T00:40:10 >>> dev-qt/qtwebengine: 4:57:55

As expected. Webkit-gtk compiles quite a lot faster with jumbo-build.

[tckosvic]

I just did an emerge update and emerge compiled two different versions of qtwebengine in one emerge task. These were 5.15.14 and 6.7.3. This took about a day and a half on a reasonably fast i7 chip with 6 cpus dedicated to the task.

I am not sure how this could occur. Anyone with any insights?

[logrusx]

I just did an emerge update and emerge compiled two different versions of qtwebengine in one emerge task. These were 5.15.14 and 6.7.3. This took about a day and a half on a reasonably fast i7 chip with 6 cpus dedicated to the task.

I am not sure how this could occur. Anyone with any insights?

When two versions can coexist, they are given slots, so that applications requiring different versions can still coexist together. You emerged two different slots. Whether you have applications that necessitated it or you just had qtwebengine in world and portage found the update.

Best Regards,
Georgi

[Zucca]

I needed to compile qtwebengine on my main laptop.
With AMD Ryzen 5 3500U and non expandable 8GiB of RAM from which 6.7GiB is available (the missing is used by iGPU). So I chose to go with USE="-jumbo-build".
Although the CPU has 4 cores and 8 threads I normally let portage use 4 per build process so that I can still use the laptop while updates are being built. Also if I was to set jobs any higher I think I'd run out of memory.
Because of the lack of memory, I also used the NVMe SSD disk space for PORTAGE_TMPDIR since the temp files for qtwebengine take a little over 6GiB at worst.
Lastly, I use a daemon which downclocks the CPU so that the fan doesn't make too much noise.

And...

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NBLK-WAX9X ~ # qlop qtwebengine
2024-11-04T02:57:11 >>> dev-qt/qtwebengine: 28:01:00

... Yeah. I understand why some people like to use binary packages.
Yes. I did quickpkg'd that after the compilation.

I think I could only speed up the compilation by letting CPU clock as high as possible.
My rough guess would be that the compilation would then take 16-18 hours.

I think I'll set the minimum RAM requirement for my future systems to 16GiB.

[logrusx]

I think I could only speed up the compilation by letting CPU clock as high as possible.

viewtopic-p-8842339.html#8842339

Best Regards,
Georgi

[Zucca]

Yeah. I could use ccache for bigger packages. But at this point the only package really needing it would be qtwebengine.
Every other package I have on my system compiles in under 5 hours or so. Night time builds.

If qtwebengine stays on my system I will consider ccache.